Inconsistencies in Awakening

Question: Towards the beginning of Warbreaker, Vasher uses his shirt tassels by saying"Upon m call, be as my fingers and grip." Later though he adds the words "what they must" to the command, with a similar addition to the legs command. Why did he change them?
Answer: Awakening requires specific wording for Commands, in addition to the right visualizations and sufficient focus.
It's not explicitly explained, but plausible possibilities include (in decreasing order of likelihood, per my personal feeling of plausibility based on the text):

Vasher is still working to discover the best Command for this task
Vasher wants subtly different behaviors from the tassels in each
case, hence different Commands
Vasher is managing his store of Breath (this seems less-than-likely
to me, but I can't exclude it)

The importance of specific, precise wording comes up in lots of places in the novel, along with support for each of these.
One of Denth's early lectures to Vivenna on Awakening gives an example of specific, suitable (or perhaps, more efficient/effective) Commands needing to be figured out:

"That's part of it. That and the discovery-- again, by one of the Five Scholars, I forget which one-- of some new Commands. If you really want to be an Awakener, Princess, that's what you have to learn. The Commands. (Chapter 33)

From a subsequent part of that same lecture, we see a specific reference to Commands' wording being important (if not necessarily decisive). Note the use of the indefinite article in a good Command:

"Well," Denth said, "there are a lot of Commands. If you want to bring a rope to life-- like that one you tried to use back in the alleyway--a good Command is 'hold things.' Speak it with a clear voice, willing your Breath to act. If you do it right, the rope will grab whatever is closest. 'Protect me' is another good one, though it can be interpreted in fairly strange ways if you don't imagine exactly what you want." (Chapter 33)

An example of an appropriate (or sufficient, depending on how you want to think of it) Command being needed:

Awakeners could recover Breath they invested into objects; she'd been tutored on that. She just didn't know the Commands to do it. (Chapter 35)

A Command can still work, even if it's not the ideal wording:

"Type Two being Mindless Manifestations in a Deceased Host. They are cheap to make, even with awkward Commands." (Chapter 46)

Commands require varying amounts of Breath, and so it's conceivable that a specific Command might be chosen as a function of how much Breath the Awakener wants to bestow (though I don't think that's the case with Vasher's sleeve tassel Commands):

"Lifeless can be created at will, and require only a few Breaths to Awaken-- anywhere between one and hundreds, depending on the Commands used--and they feed off their own color when being Invested. (Chapter 46)

Complicated Commands are much more difficult to use than simple ones, suggesting that perhaps Vasher is still fine-tuning this one:

"Right," Vasher said. "As you've seen, most basic Commands work easily. If the Command is something the object could do, and you state it in a simple way, the Command will usually work."
"I tried some simple Commands,", she said. "On the rope. They didn't work."
"Those may have sounded simple, but they weren't. Simple Commands are only two words long. Grab something. Hold something. Move up. Move down. Twist around. Even some two-word Commands can be more complicated, and it takes practice visualizing--or, well, imagining." (Chapter 46)

And Vasher explicitly states that there are Commands that are not known, suggesting again that specificity in Commands really matters:

"This area is where you really begin to understand how little we know. There are probably thousands of Commands we don't know. The more words you add, the more complicated the mental component becomes, which is why discovery of a new Command can take years of study." (Chapter 46)

and

"It doesn't help that a lot of people who learn new, valuable Commands never share them, and probably die with the knowledge." (Chapter 46)

However, in favor of (3), see

The shirt quivered and a group of tassels curled up around his hand. Five of them, like fingers.
It was a difficult Command. It required far more Breath to Awaken than he would have liked--his remaining Breath barely allowed him the Second Heightening--and the visualization of the Command had taken practice to perfect. (Chapter 21)

So Breath rationing is plausible, since we know that Vasher would prefer not to use so much Breath on this Command. And, from some of the above excerpts, we can deduce that more awkward Commands require more Breath than better ones. But if we presume that the more precise Command is better (Breath-wise) then it would be odd for Vasher to prefer the "worse" one when he is explicitly concerned about how much Breath it requires.

In particular, note that Vasher's second Awakening of the sleeve tassels is more specific than the first one we see. This is why I find the first possibility most compelling. Vasher is a practiced researcher of Awakening, and as such refining the Commands he uses after seeing an earlier attempt in action seems very in-line with that.
Relatedly, Vasher is an extremely skilled Awakener. Sloppiness with phrasing his Commands seems difficult to accept, which is again why I prefer possibilities (1) or (2) from my list (I'm not sure how we'd differentiate between those two based on what's in the book alone).
Finally, while Vasher almost certainly has the knowledge, skill, and experience to do something like manage his store of Breath with a fair amount of precision (this is explained in an author's annotation describing the "Fetch keys" Command given while he is in prison in the prologue; but that is outside the scope for this question), we don't have any indication that he is stingy with Breath (and some suggestion of the opposite attitude).
So, based on the presented in-text evidence and Vasher's background, I think it extremely likely that Vasher is working to refine a new-ish, effective Command. It's also possible that he wanted differing behaviors in each instance, and so used slightly different Commands, but I find little active support for that possibility over (1), and so I prefer (1). And I cannot rule out Breath-rationing as the reason, but there is little direct evidence of it in this application and so I find the case for (3) to be unpersuasive.
Comment: Honestly, I have my doubts about 1) in this case.  That seems like a pretty common use of awakening, and Vasher, being one of the 5 scholars, seems likely to have meticulous knowledge about such common commands.  That just seems like the type of commands that the 5 scholars would have worked out in detail long before they awakened a sword.
Comment: @JMac The evidence isn't conclusive, so I can't say you're definitely right or wrong. But I don't agree that this is a common use of Awakening. It's a pretty complicated Command (long, highly conditional, requires practice, and is explicitly described as difficult in Chapter 21). We have zero other examples of anyone using it without observing Vasher do it first (though the commonness of tassels on T'Telir might be derived from such an application). And Vasher is very clear that a huge number of Commands are not yet known. The simpler version is described as using a lot of Breath, though.
Comment: We actually have one very prominent example of someone else using a very similar technique, without Vasher, when Susebron gets his tongue back.  It seems like a fairly intuitive awakening for highly invested awakeners, and we know Vasher used to have a _very_ large store of breaths. He literally studied awakening for centuries, and had access to enough breath to have intuitive understanding for a lot of that time.  It just seems really unlikely to me that he was still trying to streamline that process when he already knew things like awakening steel and making his phantoms.
Comment: @JMac Susebron is a special case, being so powerfully Invested with Breaths, and that also gives leeway on Command precision. Vasher doesn't have those advantages in these instances. It is stated in the Ars Arcanum that at the Sixth Heightening and higher more difficult Commands are **easier to master and to discover**, and this is explicitly *not* a basic Command. It's definitely possible that Vasher discovered this one ages ago, but it's not like you learn everything in Command tier 1 before learning Commands in tier 2-- advanced knowledge doesn't mean knowing all "easier" knowledge.
Comment: But anyways, it's more a process of elimination than an active support for (1), since inference is all we've got to go on. I find (3) to be less than compelling, and (2) is plausible but has more issues than (1). So I land (tentatively) on (1), or else the answer is totally outside of what the text offers support for.
Comment: My point is that Vasher had a large period of time where he was able to master and discover a lot more about awakening than anyone else we've seen, perhaps excluding Denth.  That's why it doesn't make sense to me that 1) is most likely.  Considering the depth of Vasher's knowledge, it just doesn't seem likely to me that he was actually trying to refine a technique there, especially one that he likely has used before (it seemed more like a tool in his toolbox than something he made up on the spot).  Putting 1) ahead of 2) just seems strange to me given Vasher's history.
Comment: @JMac Again, definitely possible. But just because Vasher knows *a lot* about Awakening doesn't mean that he knows *every Command* and its most perfect phrasing-- he definitely doesn't. I don't think that Vasher was making it up on the spot when we first see him using it, I think that he's *continuing to refine* this specific Command. And while (2) is definitely possible and consistent with other information we have, we have no information at all on what differences Vasher might have been trying to achieve, nor a good guide as to how the Commands would differ.
Comment: But if you don't find (1) very compelling, more power to you! I don't feel that way, but I don't think either (1) or (2) is much more valid than the other, absent additional, direct evidence. Each requires a fair amount of assumption, which is not evidence that will help determine the true reason.

Inconsistencies in Awakening


Can the ethereum attach message like bitcoin in transaction?

Question: Can the ethereum attach a message in transaction? for example, l want attach the message "hello" in common transaction(not contract create). thanks
Answer: Yes, every transaction has a data field. In the case of calls to smart contracts, the data field is used to specify what function is being called and with what parameters.
For a simple transfer of ether to a non-contract (an "externally owned account"), the data field is unused, so you can put whatever data you want in there.


How to take care of newly auctioned yield/price in fixed income data

Question: This is a financial data cleaning question. I have raw price and yield data for US cash treasury across the curve. In the time-series there are jumps on the day after the treasury auction results come out. Prior to using the data, is it good practice to manually remove the jumps? Thanks.
Answer: No, do nothing. It is important to have "as-of" data for backtesting.

Answer below is when I misread the question and thought you were trying to smooth out jumps in the rolling on-the-run series. I thought I'd keep it for reference purpose:
It depends on what you're doing. If this is purely to show where the rolling on-the-run bond yields have been trading, then no, do nothing. Practitioners are well aware of these "rolls." (Make sure your computational convention is correct – WIs should be computed using the US Treasury method for forward settlement on the issue date.)
If the time series is used for relative value trading, then these data need to be processed. The most common technique is to build a spline that generates constant maturity par yields.
Comment: Yes this is for relative value trading. The day after cash auction, the new cash/futures hedged spread will jump since we convert price in ticks to price in decimals to calculate the spread, then back to price in ticks in 32nd for ease of charting. Do you have any recommendations on constant maturity par yield material that I can read? Thanks.
Comment: I see what you're doing. For this purpose, par bonds are not the answer. You're better off creating synthetic constant maturity bonds as a weighted average of some neighboring issues (pick 2-3 bonds around a particularly tenor and calculate a weighted average). Also, it's always a good idea to NOT use on-the-run issues, since they command liquidity premium and financing advantage, which distort time-series analysis.
Answer: You need to have a process to fix the auction-day prices.  Often the coupon is changed and you will have a previous price for the old coupon, which causes the jump.  It happens fairly frequently; at my place we finally automated it.
Comment: If I understand what you are saying... when the coupon rate on the new cash is announced, the price jumps up or down to match the existing yield on the bond?
Comment: The when issued and the auction security just trade in yield terms.  There is no coupon yet.  But since you and I are trading the note our booking and systems need to have something in the database set up.  So your database people would pick a coupon close to whatever is trading now.  Then the marks for the day are set in terms of that coupon.  But, when the note finally goes to auction the coupon might be different as yields move.  So you now have a note with a different coupon using the original pricing.  You need to go back and reprice based on that coupon.


is zakaat applicable on childrens marriage gifts

Question: Is Zakat applicable on the money,gold and other items kept by parents as marriage gift for their children.
Comment: Salam and welcome to IslamSE the Q&A site about Islam. To learn more about our site and model i.e. what is on- and what is off-topic here I suggest you to take the [Tour] and check our [help].
Answer: As you didn't mention all the kind of gifts you refer to. You should know that any kind of wealth about which we know that it is a duty to pay zakat from if it reaches the nisaab (the amount which is the lower limit to obligate zakat) and a full lunar year (hawl) has past with it in our possession is a due to zakat, be it money, gold, silver, cows, sheep etc.. It doesn't matter if it was considered as a later gift, as even later it would be a due for zakat for your children if the conditions of zakat are fulfilled (nisaab, hawl).


i want to run the following php script continously in specified intervals of time and can be set by a user using a form. how to do this?

Question: //i need to run this script repetadly and the time interval can be set by a user
// checking the internet connection
if (!$sock = fsockopen("www.google.com", 80, $errno, $errstr,20))
    {
?>

<?php
    }

// retriving data from database and checking the site is down
else
    {
    for($i=0;$i<count($res);$i++)
        {
        $fp=fsockopen($res[$i]['url'],80,$errno,$errstr,30);
        if($fp==false)
            {
 ?>

 <?php

// writing data to database and sending mail
mail($email[0]['email_id'],"website is down",$res[$i]['url']." is down");
    $inputs=array('website_id'=>$res[$i['website_id'],
    'date'=>date("Y-m-d H:i:s"),'reason'=>"website down");
$obj3->addLog($inputs);
         }
    }
}
sleep(300);
}

Comment: did you even try to lookup up to how run timed jobs? We're not a search engine.
Comment: Try to explain the question in the body instead of the title.
Comment: possible duplicate of [PHP: running scheduled jobs (cron jobs)](http://stackoverflow.com/questions/120228/php-running-scheduled-jobs-cron-jobs)
Answer: Look at the cron service. Someone has already explained it here.
If you want it to stay in the form of a web page, automatically reloading itself, then look at the JavaScript function setTimeout.
Answer: Your problem with cron is this "and the time interval can be set by a user".
You can use cron such way, that you run script every 30 seconds or every N seconds. That is your smallest granularity for running script.
Now, if user sets that script must be run every 30 minutes, first thing you do at script is check that, if script needs to proceed - if last run was before that 30 minutes that user set. Script pseudo goes like this:
1) load last run from DB, compare it with interval - do we need to proceed, if not exit
2) do what script needs to do
3) save to the DB last run time

Of course this all is only necessary, if user needs to be able to dynamically change run interval and dont want to touch cron.
Answer: There are a few ways to do this. First, you can use cron jobs to automatically run a script at a set time. Your javascript won't work as the PHP script will be running directly on the server and you won't be able to show anything in a browser.
If you want the user to have the page open while it's doing all of this so the script can report data on the screen, I would just set the time in the URL as GET parameters mypage.php?refreshTime=1800 and then read it using $_GET['refreshTime'] and then use the following line to set the refresh time.
<meta http-equiv="refresh" content="$refreshTime">

This will cause the page to reload after $refreshTime seconds. Your PHP to do whatever it is it needs to do will run on each refresh as it does now when you load the page.
Comment: how to run a php script continously when the system is on without usng cron, because i need to set the refreshing interval dynamicaly??? can anyone suggest a method..
Comment: I did in the second part of my answer. Should I elaborate on it? What don't you understand exactly?


I have a pair of magnets that when I let go they attracted and broke

Question: I let two magnets attract from a distance and when they hit they both broke a piece off of each-other. Why did the magnets damage each-other when they collided and is it possible to put the broken magnets back together? I have powdered the small piece and keep the powdered part in a bag
Comment: Are they ceramic magnets? It may be hard to repair them, depending on the direction of the break relative to the north-south axis of the magnet. Usually, when ceramic magnets break the 2 pieces repel if you try to put them back together.
Comment: I have successful glued a magnet back together.
Comment: @M.Enns can you please reword what you said because I do not understand it
Comment: yes they are but they don't since I have a mold an powdered the small fragments
Comment: The powdered fragments will not be usable in repairing your magnets because you won't be able to re-assemble them with their original orientation.  However, they might be useful in other experiments.
Answer: most commercial magnet materials are quite brittle, and smacking the together will often cause them to fracture. you can indeed glue them together. Try some cyanoacrylate ("crazy glue").


How to Install Mathematica 10 on Ubuntu 14.04 Step by Step (I Am Brand Spanking New to Ubuntu)

Question: I am trying to install Mathematica 10 on Ubuntu 14.04, I have acquired the program in the downloads folder but I am unable to extract the file upon right clicking and hitting "extract here". I did read around about some of the ways others have gotten Mathematica to run, however being a complete newbie, I did not understand what specific things meant (Mounting to a CD, as well as what commands meant) and many of the steps I had to take to install it. How can I get Mathematica 10 and all its functions to install from start to finish? Also being new, I would like to learn as much as I can to become really effective in Ubuntu, if anyone knows of any resources to get me up to speed could you list them? I would greatly appreciate it! I am starting off with the book Ubuntu an absolute beginners guide. Hopefully I can become effective and independent so I don't have to continue to ask bad questions. Thank you so much!
Comment: sagemath is a open source alternative for mathematica
Answer: This article provides a pretty good starting point.
  Installing Mathmatica on Unix and Linux
For us to be able to help you further you need to provide more exact information on where you're stuck.  It sounds like you downloaded the program.  Do you know the format of the download?  (For example, does it end in .tar or .gz?)  Unlike Microsoft Windows, clicking on stuff in Ubuntu will often lead to more harm than good.
Are you able to open a terminal window to get to a command line?  Can you get to the directory where the file is downloaded?  (Probably /home/[username]/Downloads)
Post more info and we'll get you through it.
Comment: This link is broken
Comment: Hello! Thank you so much for your response! I downloaded the file Mathematica-10.0-Linux.zip. So I am guessing it is a zip file, I think I do know how to get to the command line using ctrl+alt+t. I know the file is located in my downloads folder but other than that I am kind of stuck. I did try to mess around with some of the other suggestion on the different sites but I know I am far to inexperienced to understand what the inputs and the results really meant.
Comment: I did try to resolv mathematica.serc.iisc.ernet.in: and it looks like the problem starts there, my server is unable to find it so I tried to learn a bit more about DNS settings through the link; however I was unable to access that webpage, it says 404 Not Found.
Comment: Inside the file Mathematica-10.0-Linux.zip file is a us_state.shp file. I have no idea what that file is but when I double click on that it says I am unable to extract the file.
Comment: Can you give us a list of all the files in the zip file?  Is the shp file the only file?
Comment: the  link is broken
Answer: Sorry this came extremely late, but ultimately I was able to use the command terminal to acquire mathematica on my computer as Rick Chatham suggested. I acquired a book "The Linux Command Line: A Complete Introduction" by William E. Shotts and by gaining an understanding of the command line and how to use it I was able to install it by changing directories to my downloads and then utilizing sudo apt-get install .
Comment: However, this did require that I download mathematica from a different source, and I did not actually have to complete the mounting process.  Thus one could say that the Mounting problem is still an issue however one can work around it.


How can I change this spacing?

Question: How can I change this spacing between text and table?
Comment: [Welcome to TEX.SE!](http://meta.tex.stackexchange.com/q/1436/82917) While I strongly suspect that some user here might be able to read minds `:-)`, unfortunately most of us can't, and we actually need to look at some code. Please provide a full [minimal working example](http://meta.tex.stackexchange.com/q/228/82917) which reproduces the issue, possibly starting with `\documentclass{...}` and ending with `\end{document}`. In this way we can copy-paste the code and look at the problem without resorting to wild guesses about what you are doing.
Comment: The picture is placed at the very top, the table at the very bottom. \raggedbottom could be a try with global consequences.
Answer: My first answer!
Sorry, I have not seen any attachment, maybe you can tell me how to find it.
As for this question, <code>\vspace</code> can meet your requirements, my code is like this:
<code>\usepackage{tabularx}

\begin{table}[H]
\vspace{-0.5 cm}
\caption{This is caption}\label{table1}
\begin{center}
    \begin{tabular}{ccc}
        speed & 15000 & 20000\\
        speed & 28138 & 25463
    \end{tabular}
\end{center}
\end{table}
</code>
But also, the floating format influences the spacing between paragraphs, please check your context.
Comment: Awesome that you're making answers! Just a pointer: The OP (and future TeX-ers with this problem) probably would find it better if the code you provide is actually runnable out of the box. E.g. it should have a `\documentclass` and `\begin{document}`/`\end{document}` in addition to the you  use (which you have added here).

How can I change this spacing?


SQLite "INSERT OR REPLACE INTO" vs. "UPDATE ... WHERE"

Question: I've never seen the syntax INSERT OR REPLACE INTO names (id, name) VALUES (1, "John") used in SQL before, and I was wondering why it's better than UPDATE names SET name = "John" WHERE id = 1. Is there any good reason to use one over the other. Is this syntax specific to SQLite?
Answer: UPDATE will not do anything if the row does not exist.
Where as the INSERT OR REPLACE would insert if the row does not exist, or replace the values if it does.
Comment: In this question http://stackoverflow.com/questions/690632/how-do-i-update-a-row-in-a-table-or-insert-it-if-it-doesnt-exist it is stated that replace into will always delete the row first while update doesn't
Comment: To explicitly state the implication of @Seppl's helpful comment: _always specify the complete set of values you want in the "updated" row_; since the old row gets deleted first, none of its values are preserved.
Answer: Another fact to notice: INSERT OR REPLACE will replace any values not supplied in the statement.
For instance if your table contains a column "lastname" which you didn't supply a value for, INSERT OR REPLACE will nullify the "lastname" if possible (if constraints allow it), or fail.
Comment: +1; to put it differently: always specify the _complete set of values_ the "updated" row should have - no existing values are preserved; the reason for this behavior is that is in fact not an *update* operation for existing row, but a deletion, followed by a re-insertion.
Answer: REPLACE INTO table(column_list) VALUES(value_list);

is a shorter form of
INSERT OR REPLACE INTO table(column_list) VALUES(value_list);

For REPLACE to execute correctly your table structure must have unique rows, whether a simple primary key or a unique index.
REPLACE deletes, then INSERTs the record and will cause an INSERT Trigger to execute if you have them setup. If you have a trigger on INSERT, you may encounter issues.

This is a work around.. not checked the speed..
INSERT OR IGNORE INTO table (column_list) VALUES(value_list);

followed by
UPDATE table SET field=value,field2=value WHERE uniqueid='uniquevalue'

This method allows a replace to occur without causing a trigger.
Answer: The insert or replace query would insert a new record if id=1 does not already exist.
The update query would only oudate id=1 if it aready exist, it would not create a new record if it didn't exist.
Comment: I don't think this is right. The sqlite documentation (as of 1st July 2010, version 184.108.40.206) says that `REPLACE is an alias for INSERT OR REPLACE`, and would hence have the same behaviour. In my experience this is the case..
Comment: @fostandy REPLACE is indeed an alias for INSERT OR REPLACE, but the answer on which you're commenting is talking about UPDATE (because that's what the question was about).
Comment: I think it will do a delete->insert if it finds a conflict


Was Rorschach's Pagliacci joke a real joke?

Question: In Watchmen, Rorschach is reminded by The Comedian of a joke he heard once:

"Heard joke once: Man goes to doctor. Says he's depressed. Says life seems harsh and cruel. Says he feels all alone in a threatening world where what lies ahead is vague and uncertain. Doctor says, "Treatment is simple. Great clown Pagliacci is in town tonight. Go and see him. That should pick you up." Man bursts into tears. Says, "But doctor...I am Pagliacci."

Was this an actual joke outside of Watchmen? And if it was, was it ever told in a manner that deserved laughter and a roll on snare drums?
Comment: "was it ever told in a manner that deserved laughter and a roll on snare drums?" — what, in the real world? I think that is a little outside of our scope.
Comment: I heard it as a kid in the 60's.  It was told wryly to me though, not "*Ha! Ha!*" funny.
Comment: I wasn't aware the joke was so historically relevant. Thinking more along the lines of "Was it ever considered a funny joke, as opposed to being as sad and ironic as Watchmen puts it?" Based on the below answer, that appears to not even be close to the case.
Comment: @TylerH From the end of the quote, on a panel that I had some difficulty getting a hold of: "Good joke. Everybody laugh. Roll on snare drum. Curtains." If I got it wrong, Rorschach got it wrong too.
Comment: *"Was [it] a real joke" / "an actual joke"* - what's a *real* joke?
Comment: @Obie 2.0 My only hope now is that I've managed to introduce an entire new generation of readers to the Sad Clown genre of opera.
Comment: The only times I've heard it (at least once prior to *Watchmen*), no, it was never in a bada-bing sort of way. Always melancholy. Like clowns.
Comment: Since when does a roll on a snare drum follow a laugh? Do you mean [this](https://www.youtube.com/watch?v=kHYiyv68q2o)? (That's not a roll)
Answer: Yes
The roots of this joke are very old, and it has been attached to a variety of clowns since its inception.
As noted here:

That's a famous story, sometimes told as a joke, often related as
fact. It's really your archetypal "sad clown" story, and indeed
exactly the same tale has been told of other clowns, most notably the
Swiss clown Grock (Charles Wettach, 1880-1959).

Here is one version that predates Watchmen, told of the comedian Joseph Grimaldi:

It is said of Grimaldi that he felt his work so keenly that as soon as
his performance was over, he retired to a corner and wept profusely.
Here was a man of tender heart and generous impulses.
There is a story
about him which has been handed down by many generations of clowns. It
goes on to say that once Grimaldi became very ill and despondent. He
went to consult a great London specialist. The great man looked him over
and then remarked:
"Go to see Grimaldi, and laugh yourself well."
The clown looked at him sadly and replied:
"I am Grimaldi."

Another version was told of the clown Grock:

A story you may or may not have heard relates how, in the mid 1930s or
thereabouts, a prematurely old-looking man asked his chauffeur to
drive him to the consulting rooms of Charles Prelot, Academician, doyen
of French psychologists and you name it, who'd set up his trading pad
in a small palace behind the Quai d'Orsay. After half-an-hour of the
usual rigmarole, it emerged that the worried patient was very rich,
acutely depressed, and given to bouts with bottles of green stuff that
smelt of aniseed balls. He remained somewhat vague about where his
bread came from.
The face of the great savant lit up. He saw both the problem and the
remedy before you could say two thousand francs.
"What you need," he said, "is a change. Go out and enjoy yourself.
Spend a little money. Start tonight. Buy a ticket to the Olympia.
Laugh with Grock for he is, you must admit, the greatest clown in
France, if not the whole world.
The patient shook his head. "Impossible," he said. How was that?
"Because," said the man sighing deeply, "I am Grock."

An old version can be found in the poem "Reir Llorando" or "Laugh Crying," by Juan de Dios Peza. It begins:

Una vez, ante un médico famoso, llegóse un hombre de mirar sombrío:
«Sufro le dijo, un mal tan espantoso como esta palidez del rostro
mío.»

Or

Once, before a famous doctor, there arrived a man of somber demeanor. "I suffer," he said to him, "an evil as frightening as the pallor of my face."

The doctor of course suggests that he go see the great clown Garrick: "all who see him die of laughter," and "he has an astonishing artistic gift."
And the man replies:

¿Y a mí, me hará reír?
¡Ah!, sí, os lo juro, él sí y nadie más que
él; mas... ¿qué os inquieta?
Así dijo el enfermo no me curo;
¡Yo
soy Garrik!... Cambiadme la receta.

In English:

And me, he will make me laugh?
"Ah, yes, I swear to to you, he will, and no one other than he, but...what bothers you?"
The patient said, I will not recover thus: I am Garrick! Change my prescription.

Since that poem can be found here, the joke was already at least 100 years old when Alan Moore used it.
There's even a version that references a nonspecific "clown" from three years before Watchmen was published.

The disturbed man blurted out, "But Doctor, I am the clown!"
Each of us, even the clown, is subject to periods of depression and blues.

This also makes it clear that, even before Watchmen, the context was generally less humorous and more philosophic. So no snare drums.

It is worth noting that the word Pagliacci translates to "clowns," and thus may stand in for a generic clown.
It also is very likely a reference (direct or indirect) to the opera Pagliacci. In particular, the subject matter of Smokey Robinson and the Miracles' "The Tears of a Clown" is quite apropos and might have served as an inspiration:

Just like Pagliacci did
I try to keep my sadness hid
Smiling in the public eye
But in my lonely room I cry

This is mirrored in the original opera. Canio plays the role of Pagliaccio, or "Clown," a clown in a circus. He has discovered his wife is with another man, and is "wracked with grief." In translation:

CANIO:
Perform the play! While I am racked with grief,
not knowing what I say or what I do!
And yet...I must...ah, force myself to do it!
Bah! You are not a man!
You are Pagliaccio!
Put on the costume, the powder and the paint:
the people pay and want to laugh.
And if Harlequin steals your Columbine,
laugh, Pagliaccio, and all will applaud you!
Change all your tears and anguish into clowning:
and into a grimace your sobbing and your pain...
Laugh, Pagliaccio, at your shattered love!
Laugh at the sorrow that has rent your heart!
(Grief-stricken, he goes out through the curtain.)

From this, Pagliaccio (or the similar Pagliacci) has become something of a cultural stand-in for the sad clown, the performer who weeps on the inside while making others laugh. As such, his is an obvious name to associate with the Grimaldi "joke."
Comment: "bottle of green stuff that smelt of aniseed balls" Absinthe, then?
Comment: @JAB - I suppose so. The implication is definitely alcohol usage.
Comment: There's a quote from the New Testament that uses the same concept as the Comedian's joke:
Answer: Yes.
It's been told about George Fox, "the American Grimaldi"— who sadly ended his days in an asylum, having been slowly poisoned over the years by the high levels of lead in his greasepaint.
As told here:

One such story was told of George L. Fox, one of the great mimes and
  pantomimists. It was said that he went to a doctor to try to rid
  himself of a persistent case of depression. After an examination which
  disclosed nothing organically wrong, the doctor advised his patient to
  go and laugh at George Fox. The patient sadly answered, "I am George
  Fox."
Comment: This is a good answer. You found the one example that I missed. :)
Comment: Can you offer any sort of referencing to back this up?
Comment: Welcome to Science Fiction & Fantasy Stack Exchange, and congratulations on a good first answer.
Answer: The "Good Joke. Everybody laugh. Roll on snare drum. Curtains." is layered with irony, because the story here is not actually a joke, but a parable. Twisting a well-known joke into a parable that tells the reader more about the character of The Comedian is just one example of why Watchmen is so incredibly well written.
You see, the sad clown stories retold by Obie are jokes, because like all good jokes they contain a logical mixup and end on a strong punchline. Doctor tells a man to see a clown—man is a clown. These jokes, due in large part to how they are written, would get a laugh out of people in the real world—and you can tell they are all jokes because so long as you do not alter the mechanism/fundamentals of the joke, you can change much of the content and still end up with a funny punchline. For example:

A lonely man sits on a bench by a river, looking wistfully out at the
water.
"Whats wrong with you?" says another man passing by. "I can't
find love, no matter how hard I try." says the man. "Ridiculous!"
scoffs the passer-by, as if by reflex. "Here, take these 2 gold coins
and spend the night at the brothel down the road—that'll sort you
out". "No good..." says the man on the bench. "I've been running
that brothel for 14 years."

Same goes for a woman who constantly worries about her future, who is also a fortune teller, or whatever mental condition/service combo you can think of. These are all at their heart the same joke. But none of those would fit as a drop-in replacement for the story in The Watchmen because here there is a subtle difference. Pagliacci is not just sad - he is apathetic to life itself:

Man goes to doctor. Says he's depressed. Says life seems harsh and
cruel. Says he feels all alone in a threatening world where what lies
ahead is vague and uncertain. Doctor says, "Treatment is simple. Great
clown Pagliacci is in town tonight. Go and see him. That should pick
you up." Man bursts into tears. Says, "But doctor...I am Pagliacci."

This is a story of a man who sees life for what it is—harsh and cruel—which is emphasized by that action in the panels. The doctor tells him to go and see a clown, because although that provides no solution to his underlying condition, it will provide a distraction from harshness/cruelty of reality. But this idea is of no use to Pagliacci, because he cannot be distracted like the others by humour. He is the distraction.
And this all ties in to The Comedian's character, which is what Rorschach is trying to tell us with this story. He fights for justice because he couldn't be distracted like everyone else. That is his reason for being a superhero. If you now read the first two panels in light of the joke, it should be a lot clearer what Rorschach is trying to say, and why this is not a mere joke.
Answer:
You are Pagliaccio!
Put on the costume, the powder and the paint:
the people pay and want to laugh.
And if Harlequin steals your Columbine,
laugh, Pagliaccio, and all will applaud you!
Change all your tears and anguish into clowning:
and into a grimace your sobbing and your pain...
Laugh, Pagliaccio, at your shattered love!
Laugh at the sorrow that has rent your heart!
(Grief-stricken, he goes out through the curtain.)
—'Vesti la giubba' (English: "Put on your costume") from Ruggero Leoncavallo's 1892 opera Pagliacci

"Good joke. Roll on snare drum. Everybody laughs. Curtains."
Rorschach isn't saying that the joke he just told is a good one, he's saying that Pagliacci is a joke to those around him, both on and off stage which reflects Rorschach's view of the Keene act. Everybody laughs. The "punchline" that The Comedian was waiting for isn't traditionally funny... The punchline is that there is no escaping from the path he laid before himself, glad-handing and "performing" only to find it brings him empty smiles. In the same way, Rorschach is "in too deep" to sway from his extreme moralism now, so he too is forced to "put on the paint and costume" and perform his part. And as the curtain closes on the story's Auguste (The Comedian), the curtain opens for our Pagliacci (Rorschach).
Comment: Is that first part a quote from the comic or somewhere else?
Comment: The first part is an english translation of 'Vesti la giubba' (English: "Put on your costume") from Ruggero Leoncavallo's 1892 opera Pagliacci. (I just reformatted it a bit to make it clearer; feel free to rollback if you don't like it.)
Answer: The joke is also used in the 1928 silent film starring Lon Chaney Sr. as the clown Flik. He is afflicted with crying all the time while another man, also a patient of the same psychiatrist, is afflicted with uncontrollable laughter. The psychiatrist tells the laughing man that he needs to find someone worthy of his love, and when he loves her, the laughing will stop. And then he tells Tito (not knowing anything about Tito's private life ), that he needs to find something to laugh at, and points out the window to a poster on the side of a building of clown team Flik and Flok, and says "Flik makes everybody laugh. He will make you laugh too". And Tito responds "but I am Flik"
When I saw the movie, I immediately said to myself "I know that joke!" and sure enough, it was from Rorshach that I had first heard it.
Comment: Hi, welcome to SF&F.  Can you name the film?  It would be nice to have a link to it.
Comment: "Laugh, Clown, Laugh" is the 1928 Lon Chaney silent movie where he plays Tito.
Answer: The joke is even older and dates back at the end of the XVII century, when jokes about the great doctors of France were in fashion. Protagonist is an actor of the italian "Commedia dell'Arte" who in life plays the role of Arlequin. Same developement as above.
Comment: Hi, welcome to SF&F!  You should [edit] your comment into your post, and if possible provide a reference to an appearance of the joke.
Comment: Sorry, forget to say that the great clown Grock possibly took the joke from the same source i quoted above, being the Commedia dell'Arte and the clown art strictly connected in theatre history


Misra standard for embedded software

Question: I have a requirement to make a large amount of code MISRA compliant.
First question: Can somebody to give an estimation for passing well written code for embedded system based on experience. I understand that "well written" is poorly defined and vague so i ask for raw estimation.
Second question: Any recommendation for tool that can be customizable (i.e allowing suppress specific warnings) and used in automatic build environment (i.e command line interface)
Any other useful suggestions that can help with this task.
Thanks Ilya.
Comment: This question depends a lot on which version of MISRA you need. The latest 2012 version is still lacking tool support from many companies.
Answer: I also highly recommend PC-Lint.  If you happen to be compiling your code with Visual Studio I recommend a plug-in 'Visual Lint' from Riverblade.  If you cannot compile the code in Visual Studio, you can still run PC-Lint from the command line to good effect.
Some embedded system compilers provide MISRA compliance testing as compiler warnings.  I use the IAR compiler for Arm7/Arm9 development.  It provides an easy to configure MISRA compliance checklist right in the compiler setup.
It is difficult to come up with a rule of thumb for estimating the time it would take you to make some well written code MISRA compliant.  A lot depends on the existing coding habits of the programmers and how closely they follow the MISRA rules in the first place.
Rough estimates:
2 - 3 days to become adept at PC-Lint usage.
Initial pass at making existing code MISRA compliant:  10 to 25 percent of the time spent writing the code in the first place.
Keeping code MISRA compliant:  5 to 10 percent added to code development.  Half of this cost is changing the habits of your coders to follow the 'MISRA way' of doing things.  The other half is the extra cost of code testing and inspection to ensure MISRA compliance.
Comment: Please note that none of these tools support MISRA-C:2012. I recently asked IAR if they supported it and they didn't seem to even be aware there was a new version out...
Comment: That being said, I would recommend to get a cheap tool such as Lint. It will give hundreds of false warnings, but so will the supposedly "state of the art" static analysers that cost a fortune. Expensive tools like LDRA och Klocwork are equally buggy as Lint when it comes to MISRA checking.
Answer: Making code Misra compliant it not too much of a chore - if you follow fairly good programming practices. You might find some of the pointer rules slightly tricky, if the code you're trying to make comply has some weird and wonderful pointer arithmetic.
I'd second Greg's recommendation for PC Lint, but the open-source Splint is also worth looking at, although between them (and the compiler's warning system), I estimate you'll still only be able to cover 80% of the Misra rules - the rest will probably need to be code reviewed by hand.
Answer: I use PC Lint for static analysis of C and C++ code. It can be configured to show what MISRA rules have been violated, and it has a command line interface.
Answer: I have used a commercial tool called QAC.  The tool is able to enforce MISRA
It has a command-line interface, so you can set it up to run from a automated build environment.  The rules to be applied are configurable, but expect to have someone spending some time setting it u. The MISRA enforcement is pretty straightforward and worked well enough.  I was told (and this is just 3rd hand) that this is one of the tools some agencies (such as the FDA) use to evaluate code. Like most static analysis tools there is noise (false positives) to deal with.  The last time I used it, it didn't have a good means to mark/stop a false positive from occurring again (without changing the code it was complaining about).
I suspect a junior engineer will take up to a week (4-5 days) to get it setup (assuming they are determined to get it working as you want).
On a side note, other commercial static analysis tools likely have MISRA enforcement as well.  Reportedly (per their sales rep), Klocwork does.
Comment: Junior engineers should not be assigned to convert code for MISRA compliance. In my experience, they will end up slavishly following the tool's warnings, most of which are false ones no matter the tool. They may be causing more problems than they fix.
Answer: We had a similar problem of retrofitting Misra rules. We had some code quality issues on a large project and decided to use MISRA to improve the code quality.
We use the Green Hills compiler that has support for MISRA C rules. There is also stand alone checkers available. Depending on what you want to do it can be a bit over kill switching on all the rules. We switched one the rule on at a time to give people time to fix a limited number of similar problems else you get totally overwhelmed by the amount of errors.
Since our warnings was generated by the compiler and not by a standalone tool you see the errors as you develop and not only when you run the checker. As we continued developing we got our code compliant and not in one big bang. This also prevent old habits spoiling the new code causing you to having to rework the code again later.
Some times it is difficult to get old code compliant since nobody knows exactly how the code works. I hope you have unit tests.
Answer: I appreciate that this is an old question, but for the benefit of any other Archaeologists (or searchers), it is important to remember that MISRA provides guidelines that should not always be blindly followed.
I commend writing new code with MISRA in mind; therefore it will be a lot easier to stay compliant.
However, this is not always possible - and in particular, when trying to reverse engineer code to meet the guidelines.  In this case I suggest that you focus on the Required rules, and treat the Advisories as a bonus... cost v benefit applies here too!
Also, bear in mind that there is a deviation process - it is better to keep clean and maintainable code with a deviation, than to contrive some compliant but illegible spaghetti.

Misra standard for embedded software


Connect Mackie C1604VLZ-3 (passive mixer) to Phonic 620 Powerpod (powered) Mixer

Question: I am using powered monitors with the Mackie and have no amplifier for 2 passive monitors. I do have another mixer that is powered that I would like to use however I need to be able to control the mix through the Mackie. I am not versed at all in this sort of thing and am worried I will destroy something if I hook it up incorrectly. Please advise in plain simple non gear head talk and assist me if you have any idea how to accomplish this.
Comment: The Mackie has a `tape out`, the Phonic has a `tape in` with its own level knob in the main section. That should be the easiest solution, and bypass any processing (except the main EQ) on the Phonic. Set all other inputs to minimum level to avoid hiss.
Comment: How many different monitor mixes do you need? If it's only the one, use the passive monitors as extension speakers from the powered monitors.Check impedances but generally if there's a speaker out on an active monitor, it's there for another speaker to be plugged in.
Comment: What is your application? I assumed you wanted to set up two sets of monitor speakers in your studio, @Tim seems to think this is for a live situation.
Answer: To summarize:
You can plug the Mackie tape out into the Phonic tape in or:
If the impedances and resistances for the passive monitors match, then plug the passive monitors into the powered monitors' extension speaker jacks. Checking the impedances and resistance is very important because if they mismatch you could damage your speakers.
Answer: Aux sends can be connected from the Mackie mixer to the Phonic's channel inputs.  If the Mackie's total output is needed to one channel, any of the line outs can be used to send a signal to one or more channels of the Phonic powered mixer. Choices are main outputs and monitor outputs from the Mackie.
The outputs are line level which is very compatible with various devices.  Turn all volumes/gains to zero, and EQs to middle. Make the connections using instrument cable (not speaker cable) then do a sound check by raising levels on the Mackie and the Phonic to balance output/input. Adjust EQs as needed on each mixer.


How to check template on safari desktop and mobile without mac?

Question: I am developing a HTML/CSS template. I am using Fedora Linux platform to write codes and test pages.
For test my template on safari (especially mobile version) I have some trouble without any apple device.
I want to know how to test properly my template output like its real output on apple desktops or mobiles?
Answer: You have three options:

Buy some Apple devices just for testing.
Install Safari on Linux using Wine and trust that mobile devices work enough like it.
Subscribe to a cloud-based browser testing service that lets you view any URL on a variety of actually web browsers and devices.  Here is an article that lists 10 of them and what features they offer.

I have personally chosen to use the third option.  I pay $300 USD per year for one of those services and always have access to whatever browsers I need to test my websites.  That ends up being way cheaper than buying my own devices and its a lot less hassle than trying to install a variety of browsers and mobile simulators locally.


Are there differences between Google Patents, Espacenet, The Lens and PatentScope?

Question: Before I begin an extensive search, are there important differences between Google Patents, Espacenet, The Lens and PatentScope; or is it a matter of usability/preference?
Answer: Yes - there are differences amoung these and others. The number of fields you can independently search with google patents is very limited and they are thought of as missing some recent documents. Unlike many others they do not have a way of setting up an account where you can save your work or any analytics. The Lens and others can give you charts of what inventors and applicants, assignees or classifications are the most prolific in a set of search results.
But google patents is always improving - I noticed a selection criteria today - "litigation" that I had not noticed before. And they are very forgiving of misspelled search terms, just like Google searching.
I just searched for patent documents from a large family of patents I filed for a client. With google I got two hits, one for a U.S. patent and another that somehow represented many others. In The Lens I got 31 distinct hits.
Although it is only U.S. patents, the USPTO site has very fine grain searching of fields. I wanted to find U.S. patents with assignees in my city of Long Beach, CA. Since I stopped my subscriptions to expensive paid patent search sites I looked in the free ones and no other site had the ability to narrow down by assignee city.
PatentScope and Espacenet are similar, they both allow creating a free account. like the Lens for saving your work. They allow downloading results as a spreadsheet.  I just noticed Espacenet offers downloading results as a single PDF of all the first pages. If the primary drawing is likely to be helpful this is very valuable.
One thing to look for are the set of boolean operators a search offers. Some offer and some do not offer a "NEAR" operator. Many documents might have the terms "wire" and "a mile long" but you might be looking for one where the two terms are within the same sentence or paragraph or within 10 words rather that 20 pages apart.
I would advise learning the tricks and capacities of one very well but also double check you haven't missed something by using at least on other.
WIPO has a page that compares patent databases. There is a site called Intelogist that provides reviews, news and commentary on patent searching.
I hope others post more comprehensive and complementary answers.
Comment: It is a way to be helpful with my knowledge without taking on any responsibility.
Comment: Your website shows that you are retired, so I appreciate your helpful answers.
Answer: As an aside to George Whites excellent answer, if you know the patent or application number, Google Patents is generally the fastest way to the document. That said, I greatly prefer The Lens. When searching my own name on Google Patents, I have trouble getting all my patents listed. The Lens always reports them all. I think this has to do with Google Patents grouping by patent family, but either way it's annoying.
Comment: In the case you mention, I also prefer Google Patents when downloading the PDF of the publications. The PDF comes with OCR whereas the PDF provided by Espacenet normally does not.


Interaction term usage

Question: In which case should I use an interaction term in regression analysis? What does it depend on that I should be using it?
Answer: When you interpret coefficients in regression analysis, you look at the effect of one unit increase in a predictor that is associated with the coefficient on the response variable, while holding other variables constant. However, this ignores the scenario in which predictors have an effect on each other.
For instance, in a multiple linear regression setting, we have a model:
$$\text{Pollution Level in a city} = \beta_0 + \beta_1 \text{Population} + \beta_2 \text{Number of Cars}$$
Normally, if the population increases by 1 (million or thousand), pollution level will be increased by $\beta_1$, while we hold the number of cars as a constant. However,this is inappropriate because with more people, we would expect the increasing purchase of vehicles. Therefore, if we add a interaction term, we will have:
$$\text{Pollution Level in a city} = \beta_0 + \beta_1 \text{Population} + \beta_2\text{Number of Cars} + $$$$\beta_3 \text{Number of Cars} \times \text{Population}$$
$$=\beta_0 + \beta_1 \text{Population} + (\beta_2 + \beta_3 Population) \text{Number of Cars}$$
Thus, the increased population will also have an impact on the coefficient associated with the number of cars, which allows us to model the pollution level non-linearly. So if you see a non-linear pattern in the residual plot and you suspect that changes in one predictor would have effect on another, you probably should try to include an interaction term.
Comment: Thank you Jack Shi for the answer. It is quite helpful. As you have mentioned here that if I see a non-linear pattern in the residual plot then I should consider adding an interaction term. Is there any other case scenario where I should consider adding an interaction term?
Comment: The main reason is that one is substantively interested in that interaction effect, e.g. has the effect of parental background on offspring's educational attainment increased or decreased over time.
Comment: @RahulWadhwani Non-linearality in multiple linear regression can be caused by many factors. A transformation of a predictor or several predictors may also be a simple, valid solution. Or the relationship between predictors and response variable is not linear to begin with, in which case you might want to try polynomial regression, etc. If you feel like there might be a relation between two predictors in your model, an interaction term may be worth a try. Also, you should notice that including an interaction term may also introduce collinearity in the model.

Interaction term usage


Conga usage statistics

Question: I'm generating documents with custom button which leads to Conga composer. Is there any way I can get a statistics/report - how many documents were generated using this button, or using Conga in general?
Answer: Ok, figured that out. Conga has own report "Recent Activity", in Conga Composer Setup, also there is "Activity logging" checkbox while generating a document - corresponding task is created in Salesforce.

Conga usage statistics


What damage does accidentally throttling too much before you clutch up into a gear change do?

Question: How much damage does over throttling slightly as you clutch up into your gear change do? I've been guilty of this a couple of times in my new ecoboost fiesta which ive had a couple of months now as the clutch is quite heavy and hard to get used to! Oddly I've driven two 2016 models of my car which is the 2015 spec and didn't have this issue with either of them despite the fact both models are exactly the same engine and gearbox configuration. It's particularly difficult to transition smoothly in to second from first. I'm massively paranoid about causing more wear than necessary especially as where I live our sort of driving on our horrible little roads causes enough wear and tear as it is
Answer: In the short term, there's no damage. If you keep doing this, you may see some extra wear on the clutch plates over time, shortening its life a bit. But I doubt it'll be noticeable.
The clutch and gearbox are built to deal with some slip when you change gears. The moment that causes the most wear for the clutch, is moving off from a standstill: the clutch has one plate standing still, while the other rotates at 1000-1500 rpm. It's built to withstand this for ~10 years. When you overthrottle a shift from first to 2nd, the speed difference between the clutch plates is usually less than this.
IOW, don't worry. And as you drive the car more, it'll become easier to get the gearchange just right.
Comment: Cheers for the peace of mind dude, this one's the newest car I've ever owned so I over think practically every noise it makes and any mistakes I make!


Turn animated gif into WhatsApp sendable video

Question: I'd like to convert a short gif-animation to a video so I can send it to a friend via WhatsApp. Do you know easy ways to accomplish that (e.g. codec etc.)? Best would be doing it on the device directly but I could do it as well on a computer.
Answer: You can use this online tool to convert it: http://www.giftovideo.com/
Regarding tools, you could use FFMPEG + ImageMagick, but it's kind of tricky finding the correct options. There is some instructions here. I tried but some of the cases didn't work.
Comment: As a side note regarding the online tool, at this exactly time, they seem to be facing some performance problem, for every time you try it, you're going to end up in a queue like forever.
Comment: Nowadays FFMPEG can do it without imagemagick: `ffmpeg -i input.gif output.mp4`
Answer: If you're happy with a solution that you can use on a PC, then SuperUser.com has this:
How do I convert an animated GIF to a YouTube friendly video format?
For an on-Android solution, none of the video coverters specifically mention this but as the ffmpeg library does support this (as seen in the SuperUser answer), apps like Video Converter Android or Media Converter and so on, being ffmpeg based, should be able to do it.
Answer: Just change the extension from .gif to .mp4 in your device and forward to anyone. Only thing is that  the recipient needs to open it in gallery to see the animation.
Comment: Doesn't work in my system. Can you detail the steps for this?
Answer: I've tested this on Android 5.0.1:

Install this app: Convert GIF to Video & Share
Open the app and select the GIF you want to convert.
Choose 3gpp video codec.
Tap the convert button.
Done. Now you can send the video through WhatsApp.


Can a Raspberry pi 4 power an 2.5 ssd drive?

Question: I want to build a NAS with a single 2.5 ssd.
According to this video It should be possible. do I need a additional power supply for the hard drive?
Answer: The key thing with any Pi especially the 3B+ or 4 models is to make sure you are using a proper power supply and not a generic (or even branded charger).
Power supplies (esp. the RPF/RPT ones) are designed to cope with power surges (such as hard drives spinning up), increased number of cores (e.g. start up of programs or extra processing requirements) or demands from GPIO connected devices / HATs.
The majority of charges can drop the voltage temporarily to cope with the surge in current requirements to say nothing of initial loss over the cables.  The cheap charger cables can cause significant loss due to the thinness of them.
The older drives with two USB connectors where designed to be used across two USB hubs on laptops or PCs allowing the two chips driving the ports to provide power without exceeding the current limits of the chip (or connectors). Unfortunately, the majority of Pi boards only use one hub (despite a plethora of USB ports) so a dual USB cable may not help unless you can confirm the power draw is via two hubs.
So far, the only issue I have found with spinning hard disk drives have been the 4Tb ones - I've not been able to get them to reliably work without a powered hub - I normally get more issues from the USB / SATA interface not booting.
That last point is also worth noting - not all drives will allow the Pi computers to boot from them. Linux has spotty support for USB devices and earlier Pi boards would only boot from some adapters and not others (even though they looked the same).  A work around for early boards was to use the SD card to hold the bootcode file and load the rest from the hard drive, with another to tell the OS to load from the drive by reconfiguring part of the OS to point to the hard drive.
With a single drive NAS, I would consider using the SD card to hold the operating system and configuration and keep the data on the hard drive only.  This lets you simply copy the SD card to another machine as backup. For example, a copy of config.txt / fstab and Samba files from the SD card will get you a basic NAS up and running from backup in under 30 minutes assuming the hard drive data is not corrupt.
Comment: Do the original raspberry pi branded power supplies count as "proper power supply"?
Answer: If you want to use an SSD as shown in the video you won't need an extra power suppply.
However if you use an HDD you may need an extra power supply depending on what cabel you use to connect the HDD to your pi.
Some cables for HDDs especially older ones come with two USB cables one for data and one for power.
Since the Pi has 4 USB ports there should be no Problem setting this up.
Comment: The Rpi can only supply 1.2A in total to all USB ports so it is essential to check that the HDD will never try to draw more than this. If this is ignored, problems will happen, including file system corruption, reboots, shutdowns, etc.
Comment: this is accurate - my pi can run my SSD no problem, however a 4TB HDD it gets I/O errors unless I connect using powered USB hub.


Group objects in blender

Question: There´s a way of grouping SVG objects in blender like in Illustrator or Inkscape, where when I have to move the object the entire group move´s on together, without having to append that object to the main object?
Answer: You also can just parent them together. Select all Objects you want to group and than press Ctrl + P. All selected objects will now follow the object which was active during the Parenting process.
Comment: Sometimes, it doesn't make sense for the objects to be grouped under any particular object. For example, if you had three columns, they should be at an equal level in the hierarchy for better organization. I like creating an empty to group them together.
Comment: When I click on control + P it asks me "set parent to:" with a list of options. What do you recommend?
Comment: Usually you use Object Parent (Parent to: Object) the other settings are useful if you want to connect something without enheriting the rotation.
Comment: I think that the concept of parenting the objects in blender is quite better than the group because when you need a group you want to click and element of that group and move all the others together without the need of hitting shift+G or something similar.
Comment: Thanks for this. Took some tweaking (mainly the necessity to select the Parent lastly, in order to make the Siblings conform Parents movement), but I got it to work based on your advice.
Answer: Sort of.
Select all the object you want to group.
Press ctrl+G, you will notice a green outline appear around them.
Now in future, if you wish to manipulate the whole group:
Select a member of the group and then press shift+G and press Group and it will select every other object in that group which you can now drag around, scale etc.
Comment: I tried this and it didn't work. When I created keyframes on the timeline while moving the whole object, only one of the object's keyframe was recorded.
Comment: Ty DevTim. Is it possible to add a group within a group? (Example, Weapons: Weapon1, Weapon2, Weapon3, etc)
Comment: How do I undo this grouping?  Ah, Object->Group->Remove From Group.

Group objects in blender


Non-acceleration and 0 force

Question: If a mass is moving at the rate of 30/ft. per minute for 5 minutes on a straight line and it strikes a second stationary mass and effects a change of position to this second mass, then we know from F=ma that the force is 0 since the acceleration is 0. Then why do we say because it is 0 that there is no force when in fact the first mass changed the position of the second.
Comment: Don't forget to accept one answer by clicking on the check-mark in the left column, next to your preferred answer.
Answer: We don't say it is $0$, why is $F=0$? If the second mass was stationary, then sometime after being struck by the first mass it is in a new position, it must have undergone acceleration $\to F\neq0$ precisely because $F=ma$.
Comment: I am not referring to the second mass. For the first mass it's force is 0 because it's acceleration is 0. Then why do we say it has no force, since from F=ma it is 0, when it effected a change in the second mass.
Comment: The situation you described is impossible. Any action is balanced by an equal and opposite reaction (Newton's 3rd law). So if the second mass experienced a force from the first one, then the first one experienced the same force (in the opposite direction) from the second. It cannot be the case that 1) the first mass continues at constant velocity and 2) the second mass is pushed by the first mass.
Answer: We never say force acting is zero.We just say there is no external forces to the two masses(external force to the system is zero).This is because only if the external forces are zero(or their effect should be negligible), momentum conservation can be applied.But the force applied by one mass on the other(internal forces) is not zero.Since this is the only force acting and it acts for the same time(a short time) on both the bodies, we say the magnitude impulse on one body equals the other(opposite in direction) and thus the momentum change is also equal in magnitude but opposite in direction(since impulse equals change in momentum).
Answer: It appears you are mixing the force at one given time with the acceleration at a different given time.
Don't feel bad; it is a common beginner mistake to think that there is "one force" and "one acceleration" in a given problem.  Part of learning physics is learning how to treat values from different times, as well as values from different objects.
During the 5-minute interval, the first mass stays at the same velocity.  This means its acceleration is zero.  By $F_{net}=ma$, the net force on this object during that time interval is zero.
During this same time interval, the second mass stays at rest.  Its acceleration is zero, and thus the net force on it is zero.
The collision occurs at a different time.  Neither force nor acceleration care about what happened during the 5-minute interval, they only depend on what is happening now.  The first object is now slowing down -- a form of acceleration -- so $a \ne 0$.  This means the net force on the first object $F_{net}=ma\ne 0$.  This net force comes from the second mass pushing on the first mass.
By the Third Law, during the collision the first mass pushes back on the second mass.  This creates a net force on the second mass, which accelerates the second mass during the collision.
Comment: Thank you Dr. Shelton your explanation is crystal clear and beyond superb! It is simple, non-befuddling, incomparably better than the others. They need more physics instructors like you!!!!
Answer: Hey when the collison occur the force will act on it this force will persist until they are in contact which is given by
F =(m1v1-m1u1)/t=(m2v2-m2u2)/t=impulse/t
 Here v1 v2 are final velocities and u1 u2 are initial velocities t is the time upto which force acts or the time of contact
Here we can see that force is not 0 it will act during collison for very short period of time .Here F is the average force acting for time t.This force will be equal and opposite for both particles and force will cause the change in momentum

Non-acceleration and 0 force


javascript mailto attachment not showing up

Question: i'm trying to create a small web app wherein in one form, the user may type in certain parameters as part of the message, then after he hits a button, it will show an Outlook (depends on his default email client) email client popup with all the details he placed.. and then it will include an attachment.
the javascript code looks like this:
function submitReport()
{
  var remarks = document.getElementById('remarks').value;

  if(remarks != '')
    body += 'Remarks: '+remarks;

  var href = 'mailto:email@example.com?subject=[Bug Report]  '+menu_path+'&body='+body;

  href += '&attachment="C:\\debug.log"';

  var form = DomUtils.createForm();
  form.setAttribute('action', href);
  form.submit();
}

i tried alerting the "href" variable and it shows:
mailto:firstname.lastname@example.com?subject=[Bug Report]&body=message_bodyReport Type: MonthlyStart Date: 2010-05-01 00:00:00End Date: 2010-05-31 23:59:59&attachment="C:\debug.log"
and surely an outclient popsup with all the subject, recepient email address, body..
but no attachment. anybody encountered this before? :(
the outlook used here is 2007..
if i run the web app in IE, it actually says an error
"The command line argument is not valid. Verify the switch you are using."
any ideas?
Answer: There is no way for a web page to cause a browser to open the user's email client with a file pre-attached from the hard disk.
Use a form and process it server side, or provide simple instructions along the lines of:

Send an email to firstname.lastname@example.com
and attach your log file.


How do you show and not tell alien biochemistry?

Question: Let's say you were thinking of making a docufiction about alien life and you wanted to do a segment or two about alien life with radically different biochemistry, such as being based on silicon instead of carbon. How are you supposed to show any of this? How can i even begin to think of what such bizarre life could look like?
Comment: this seems a bit better fit for writing se
Comment: This looks like a it might be more of a writing question than a worldbuilding question. Are you asking about what silicon biochemistry might look like, or are you asking how to present this biochemistry to your audience in something other than an exposition dump.
Answer: Maybe start looking for special chemical process that will differ from what we have on earth, and try to use it in some situation. For example, find a material the reacts with silicon but not with carbon and use it to harm the alien or something like that.
Another option could be tell in a more subtle way, like having a silicon alien calling a human a overdeveloped coal as a swearing, or calling the silicon alien a overdeveloped breast implant


Can I change the default size of a new table in macOS Pages?

Question: In Pages, I frequently have to make documents (for school) with a two by five table.  Each time I click the table button, I then have to resize the table.  Can I change the default table size, so each new table is automatically two by five?
Answer: You have a number of options available to you, such as creating a template, using AppleScript or Automator to create applications, scripts, or services, and so on.
Below is a sample script I've created based on the details in your question:
tell application "Pages"
set myDoc to make new document
tell page 1 of myDoc to set myTable to make new table with properties {column count:5, row count:2}
tell cell range of myTable
    set width of columns to 80
    set text wrap to true
    set alignment to left

end tell
end tell

Assuming you're not familiar with how to use this, below is one way you could use the above script:
Create a service using Automator

Launch Automator (usually found within your Applications folder)
Go to File > New
Select Service and click the Choose button (Note: If the 'Service' option is not available, select Quick Action instead)
In the top right hand of the window that appears, ensure that "No input" is selected from the Service receives drop-down list
Ensure the In drop-down list is showing "Any application"
In the second column containing the long list, find "Run AppleScript" and double-click on it
This will add the Run AppleScript window on the right
Now, replace the (* Your script goes here *) with the the sample script above
Save the service using a meaningful name (e.g. Create Pages Table).

Now you should be able to run the service from any application by going to the Services list within any Application menu (e.g. Pages > Services, Finder > Services, etc) and select the service you just created.
NOTES:

The set width, set text wrap and set alignment lines within the script are not required. I have included these so you know how to customise these table characteristics if you need to.
I have assumed from your question that your two by five table referred to five columns by two rows. However, you can safely change the column count and row count values in the script to suit your requirements.


GPU not powering on

Question: So I got home from work yesterday and went to turn my computer on as per usual to be greeted by this:
The screens remained black, so I rebooted; I go as far as GRUB before my screens went black again. I rebooted again, they didn't turn on. I rebooted again, I got as far as the windows login screen.
This time I unplugged it, opened it up and cleaned it but to no luck. The GPU was still being tempermental. I repeated the process of turning off and on several times until one time it work as normal. I happily played games for the rest of the night (5-6 hours?) thinking everything was jolly good now.
Well I get home from work today and it is doing the SAME thing. Sometimes everything displays normally for a few seconds to minutes then the screens go black; then sometimes the screens don't come on at all.
Summary and additional points

Screens sometimes turn on before shortly turning off, sometimes they don't; I cannot seem to determine any pattern between when they do or do not turn off.
The build has been working fine for about 8 months now so I know it's not hardware incompatibility.
If I plug a monitor into the on board graphics I can use the PC normally (just in low graphics mode)
I have two monitors and it's a case of they both turn on or not. So I think I can rule out the monitors being dead.
I have tried replacing the GPU
I have tried replacing the RAM
I have tried flashing the CMOS
I have tried cleaning the inside
The GPU is a Radeon HD 7870

My questions
Is my GPU dead?
It's not very old and I would rather have a method of being certain it's the GPU before I fork out some money I can't really afford.
I do not have a second PC here to test it in.
If my GPU is dead why does it sometimes work and sometimes not?

Update
Okay, it was working again.. at least I thought it was. I left it running for 10-20minutes with the screens black. Turned it off and straight back on and it worked for all of 10minutes. I was then updating the post in joy thinking I could play some games for the rest of the night when BAM it went black again. So yeah, I don't know :C
Comment: RMA the card. ...
Answer: Might be a bad power supply.  Try swapping it out for a new, and try to get a higher wattage one while you are at it.
Answer: Running for a while and then shutting down sounds a lot like overheating.
Based on what you say you've tried, that seems to only leave the power supply or the mother board.
You say you replaced the GPU.  I'm assuming the other GPU also failed.  That would rule out your GPU as being at fault.
Perhaps the power supply is not adequate for that model GPU?  Or perhaps the power supply is failing?
It could also be a cracked mother board.  I had one of these.  The machine would run fine for a while and then get flaky.  Finally, after moving the machine, it wouldn't come on at all. Fans would turn but no beeps and no video. I replaced the motherboard and now all is well.

GPU not powering on


SharePoint Backup

Question: I need to get back up copy of daily code changes that I made in SharePoint site. Is it possible? I have found back up options like taking back up of farm, site collection in central administration. will it take back up of my coding also? Which is best method to take backup of daily changes?
Answer: Best practice is to develop you customizations in Visual Studio as a solution. You back up your code with some source contol software like SVN or Team Foundation Server. Since your solutions are deployed as a wsp, you can save the packages easily. In case of restoring the farm you need to install and activate your solution again.
Comment: is there any in built options available for source code back up in sharepoint site..
Comment: SharePoint as an application platform does not (and will not) contain any source code management. There is (as I said) a Microsoft solution -the TFS (Team Foundation Server). But that is a seperate product. Usually you will use a tool that is not SP-specific, so that you can store your code for other applications as well.
Answer: In SharePoint... You deploy only the solution not the source code... If you need to backup... Save it seperately or use tools like VSS(Visual Source Safe).

SharePoint Backup


What kind of fuzzer can i use?

Question: I studied reverse engineering for 6 months.
And I wanna discover Adobe Reader vulnerability for bughunting.
But i have lack knowlege of this branch. Anyone help me plz?
My question is what kind of fuzzer can i use to fuzzing Adobe Reader?
Answer: It doesn't work like that.
As you might know, bugs are worth money. The main reason for tgis is at it requires both skill and time to find these bugs.
Clearly you want to learn this skill, so in the future you might be able to do this.
So, you can't just point a fuzzer at something and find bugs in A-software. You either need to write your own, statebased fuzzer or find bugs by reverse engineering.
I myself am a huge fan of the latter.
Read the docs on how it should work. Reverse a complex part (complex = programmer bugs) and audit the code.
When starting out, start with finding bugs in old software. That you know contains bugs.
Happy bug hunting!!
Edit: Read Fuzzing Adobe Reader - Exploit Development Joxean Koret posted a great comment there.

What kind of fuzzer can i use?


magnetizing current - which value must be chosen?

Question: Sometimes in app notes i see something like @assume that magnetizing current value is 10% of the primary current".
Why? How to choose the magnetizing current value the right way?
Answer: Magnetising current will be practically irrelevant in a good mains transformer design. As it's in quadrature to the load current, a mag current of 10% of the full load will increase the full load current of the transformer by 1% (Pythagorus). 10% is a very conservative estimate, it will typically be smaller.
Magnetising current is sensitive to the transformer inductance. Transformer iron varies in relative permeability from a few thousand to many thousands, depending on price, and strain history. If a transformer is built from Es and Is, or two C cores, variations in size of the inevitable airgap could cause a 10:1 change in inductance, together with a similar change in magnetising current. So magnetising current is measured on a transformer as an assembly quality test.
There are mains frequency transformers which have a different typical ratio of magnetising current to full load. Current ratio transformers will use a special high permeability core to reduce mag current even further, as it represents an error term in the current ratio. Microwave oven transformers will have a mag current in the same order as the full load current, perhaps only 1/3 or even 1/2, as they are built down to a price, run hard, and fan cooled.
Ferrite core transformers will tend to have higher relative magnetising current than iron transformers, due to the lower permeability.
Comment: is it ok if i choose 10%? It is 2-switch forward smps transformer working on 84khz
Comment: Nicely written. I also learned about using magnetizing (British spell things so wrong!) current as a quality test and that makes so much sense to me. Thanks.
Comment: @silkyre6xtenz If I was designing a ferrite cored transformer system, I would not choose 10%, I'd do the sums. If you run at relatively high field, so accepting large core losses for perhaps limited duty cycle or low copper losses, your mag current could easily be much higher than 10%, and worth designing for properly. But it's up to you. 10% makes a good 'back of the envelope' figure for gross feasibility.


Minimum number of NAND gates required to realize EXOR function

Question: While trying to minimize the number of NAND gates for realizing EXOR function,
\$A\overline{B} \ \cup \ \overline{A} B\$,
I used De Morgan's & got the expression
\$\overline{\overline{\left ( A\overline{B} \right )}\cdot \overline{\left (  \overline{A} B \right )}}\$
and hence ended up with \$5\$ NAND Gates.
But my book shows it can be done with \$4\$ Gates only.
What should be a good approach towards this minimization problem?
Should I avoid using De Morgan's Law here?
Comment: It can be done by 4. But it's a weird simplification.
Comment: Can we reduce 5 gate circuit to a 4 circuit directly or it requires re-simplification from scratch?
Comment: I did once derive it, and from what I remember it was a bit convoluted - I think it requires making it far less simple first but it was about 5 years ago when I studied it, so can't remember off the top of my head.
Answer: The 4-gate implementation of the XOR function requires the output of one of the gates to be used twice. As far as I know, there's no direct algorithmic way to come up with such solutions; they must be "discovered".
In a sense, you have to "de-optimize" the solution before optimizing it, and knowing what deoptimization step makes sense is a matter of intuition. In this case, it requires the observation* that
$$A\cdot\overline{B} = A\cdot\overline{(A\cdot B)}$$
and
$$\overline{A}\cdot B = \overline{(A\cdot B)}\cdot B$$
and then realizing that the \$\overline{(A\cdot B)}\$ term for both right-hand expressions can be generated by the same gate.

*The details:
Since \$A\cdot\overline{A} = 0\$, you can add this term to any expression without changing it:
$$A\cdot\overline{B} = A\cdot\overline{A} + A\cdot\overline{B}$$
Now, factor out the A
$$\ldots = A\cdot(\overline{A} + \overline{B})$$
and apply DeMorgan's:
$$\ldots = A\cdot\overline{(A\cdot B)}$$


MSVCR100D.DLL and dependency walker

Question: I put MSVCR100D.DLL into the c:\windows\system32 folder but dependency walker is still complaining about it being missing. Any ideas?
Comment: Which Windows version?
Comment: It is a windows web server 2008 r2 64-bit but the dll is 32-bit
Comment: And the application is 32-bit as well?
Comment: Yes the whole solution is build 32bit
Answer: Dependency walker hasn't been updated in a very long time.  I think the author just gave up trying to keep up with Windows development.  Particularly resolving side-by-side manifest lookup rules is a very hard problem to solve.  SetDllDirectory() is impossible to resolve statically.  It isn't very smart about delay-loaded DLLs and it doesn't know anything about DLL exports that are forwarders.  You almost always get a big list of missing DLLs that are not actually missing.
Using the 32-bit version on a 64-bit operating system does not work well either, your probable mistake in the case of msvcr100d.dll.  Which must be copied into c:\windows\syswow64, not system32 for a 32-bit executable.  You really want to favor local deployment for msvcrt versions 10 and up.  In other words, simply copying the DLL into the same directory as the EXE.  Putting it in the Windows system directory exposes you to too much DLL Hell, well beyond picking the wrong system directory.
If you still have trouble then SysInternals' ProcMon is the better tool.  The trace it generates shows you exactly where it looked for the DLL.
Comment: There is now an open source rewrite partially done in C#, meet "**Dependencies.exe**": https://github.com/lucasg/Dependencies. Test impression: **a bit beta-ish**, but it claims to handle API-sets and SxS (missing from Dependency Walker). **I haven't tested it enough to really recommend it** - but it is open source and hence inspectable. It seems you need to build it yourself from the source (for now). And yes, in my opinion the whole side-by-side concept is in many ways a second coming of dll-hell in a brand new incarnation.
Comment: If you are limited to using Dependency Walker, make sure you use the x86 or the x64 version that matches your project build settings.
Comment: Hans, in [a previous comment](https://stackoverflow.com/q/7378959/129130) you mention using **Visual Studio's debugger modules view** to determine dependencies. A great reminder for when you have source access. Thanks! Now, I have been mucking about trying to find some test code to determine what sort of dependencies this view shows out of the ones described in [**the Dependency Walker help file**](http://www.dependencywalker.com/help/html/dependency_types.htm). But perhaps you would know this off the top of your head? Maybe I should make this a real question instead of just a comment?

MSVCR100D.DLL and dependency walker


Identifying templates from SMS text

Question: I am building an app where I identify information from the SMS, something similar to expense management apps. I have a parser which reads all the SMS of user, identifies SMS of interest and parses useful information from it. This bit is working fine, however the problem is that I want to also score completeness and accuracy of the parser.
Completeness - Out of 100 SMS of interest, how many of them parser is able to identify
Accuracy - Out of SMS identified as relevant, for how many SMS parser is able to extract right information
I have a manual process to identify these. I take a random sample from the corpus along with parsing results and manually tag which ones are correct or wrong. I am able to identify gaps in parser and fix them by this process. However more gaps I fix more it becomes difficult to identify further gaps with this process. Also since sample is random, it has many SMS with same structure. Parsing success/failure for similar SMS is similar. Completeness and accuracy from the random sample does not correctly represents correctness and accuracy of whole corpus as well.
I was thinking that since financial SMS of interest have templates associated with them, if I can tag template of the SMS, I can keep track the templates which are known to be parsed correctly and only do manual checks on templates which are not yet tagged manually for correctness. This would also help me build tools to identify correctness, accuracy and unknown status for the whole corpus. It can also help me identify new templates as they are added to the corpus.
There are 1000s of templates. Examples of templates:
<code>Template1 - Thanks for spending INR 100 at Amazon on 1st Jan, your available credit limit is 1,000
Template2 - You have spent INR 100 on your credit card ending in 1234 at Amazon on 1st Jan 2020
Template3 - You txn of INR 100 is credited/reversed by Amazon on 2nd Jan 2020, Avl Bal - 1,100
Template4 - You account xxxx1234 has been debited with INR 500 and bene A/C xxxx4321 has been credit on 3rd Jan
</code>
I have searched a lot on google and many results which seemed relevant were from this forum. Similarity based on n-gram seemed quite interesting, but I was not able to make much of how to apply it to my problem. One of the questions which seemed very similar: Identifying templates with parameters in text fragments. However, it differs slightly in the sense that it identifies sentences with similar templates out of given corpus. I want to tag template of a sentence without looking at the whole corpus. I am okay with training a model to tag the template, but I would want the model to identify new templates which are not part of original corpus and tag them as well.
I am a software engineer and have no prior experience with data science. Please pardon me if I am not making any sense or if this forum is not the right place for this question. I would really appreciate any help in identifying the right approach and some references to understand the concepts involved.
Answer: I'm not sure I understand your problem very well but let's see.
First let me try to formalize the task as a ML problem:

Identifying the SMS of interest is a binary classification task. Your "completeness" score seems to correspond to the standard recall measure. It is usually a good idea to also look at precision, i.e. out of the SMS identified as relevant how many are truly relevant.
You don't really explain the second part of extracting information out of SMS of interest. In general this part might be some kind of sequence labelling problem (similar to Named Entity Recognition).

It's important to distinguish these two parts if you're going to use ML.
Now what you are currently doing is a rule-based system: you manually identify the patterns one by one, then the system just applies the list of patterns. rule-based systems are considered the ancestor of ML systems: as you noticed, it might be possible to automatize the part of identifying the patterns. Given that you already have labelled examples (training data), you could train a model to recognize the general patterns by itself. The main difficulty is to provide the model with the right features so that it can do the job as correctly as possible.
Note that in general it doesn't really work as a list of templates in the same way as what you do manually.
The question of identifying cases without looking at the whole corpus might be related to ''semi-supervised learning'', where a system iteratively learns to annotate unlabelled data from an small initial set of labelled data.

Identifying templates from SMS text


Changing email addresses on my @me.com and @icloud.com

Question: When I was married I started both my @me.com and @icloud.com accounts.  The accounts are my first name and last (previously married) name run together.  Now that I am divorced I don't want that as my email.  I would rather have a different name at the front of my email.  How do I go about changing both accounts to another name and getting all my devices and itunes accounts moved over.
Answer: Unfortunately, as was stated, you cannot change your @me.com or @icloud.com email addresses independently of your Apple ID. What I would recommend doing is setting up a Gmail (or other) address and using that as your primary Apple ID email (as well as all your normal email for that matter).
If you have a Mac you can even move all the email from your @firstname.lastname@example.com account to your new Gmail account simply by setting up both and dragging the folders from one mail account to the other.
After you set up a Gmail email address you can edit your Apple ID preferences at this site. That way, all you ever basically see is the new Gmail account.
Answer: Unfortunately, depending on your situation, you may not be able to change your email address. You can check this Apple support page out for details.
If you sign up for an entirely new account, you'd lose the purchases you made under your existing one.
Answer: Go into icloud mail and select preferences in settings on the left sidebar at the bottom. Select "Accounts" which will list your @me.com and @icloud.com aliases.  The @me.com cannot be changed, but you can create a new alias of the email address you would prefer.  This address will be an @icloud.com address.
Then go to "composing" tab.  Set default address to the new alias you created.  Then below that, deselect all the other email accounts and select the new alias.
This doesn't get rid of the @me.com email, but when sending mail, it will at least use your preferred address sending and receiving.  Occaisionally the @me.com will pop up, but for the most part you can just forget about that address and use your new icloud alias.
Answer: I think the easiest thing to do here would be to change your Apple ID name, which is used to form your @me.com and @icloud.com email addresses.
I haven't done this myself before, but Apple's HT5622 document includes the following, which seems to explain how this can be done:

However... I don't completely understand this (eg exactly what they mean by "Apple ID Name").  So perhaps the best approach is to contact Apple Support and ask them.  Their page for Apple ID Support is here.
Comment: PS @heather If you do contact Apple, perhaps you could record their advice here, to help other people in the future... you could write your own answer, or add a comment... Good luck!


Monzo Business Account payments

Question: Evening. Quick question realting to Monzo Business Accounts and making a payment from them. I have somebody who has one of these business accounts wanting to buy goods from me. They want bank account details (standard) as well as an email address (not standard) as well to complete the payment. This has obviously started alarm bells ringing as I have a business bank account with a standard bank and have never needed somebody's email address when making a payment. It smells of a scam to me where the person will use the email address supplied to request a change of password etc. Anybody care to enlighten me ref. this? Thanks in advance.
Comment: As e-mail is not required for making a bank transfer, you can give them a new one - just register new account on gmail/hotmail/etc. Trow away the account once you are done working with this business.
Comment: Some bank transfer systems (especially from the more recent players in the field) will let you provide an e-mail when doing the transfer to "notify" the recipient. This is usually optional. Other payment systems will use an e-mail (or phone number) to initiate a transaction, but those will not need bank details.
Answer: The Monzo help pages do not mention needing an email address - just your name, sort code and account number as you would expect.
You might find this is the start of a social engineering scam where the buyer then decides they want to use a different method and need another piece of information from you, so over the conversation they build up enough info to hack an account. Or, as you say, it could just be that they want to try using your email address to hack directly.
Additionally, if whatever you are selling is on one of the well-known sellers' platforms (eBay, Amazon Marketplace, Etsy etc) then for them to try to pay you outside of the platform is also suspicious, and would remove any seller protection that you otherwise would have had.
Either way, it doesn't sound legit. I would suggest deleting the messages, blocking them and moving on.

Monzo Business Account payments


Disable unnecessary startup services and applications

Question: What is the best practices to disable unnecessary startup services and applications? This post is very useful when i came to decide what to disable Which startup applications can I safely disable? , but i cannot find how to start! also i cannot find anything related to services.
Answer: Go to the dock and search for Startup Applications. The GUI is very simple and you can remove programs from the list to stop them from automatically starting. Only remove programs that you know are not essential.
Answer: According to UpstartCookBook:

With Upstart 0.6.7, to stop Upstart automatically starting a job,
you can either:

    - Rename the job configuration file such that it does not end with
      ".conf".
    - Edit the job configuration file and comment out the "start on" stanza
      using a leading '#'.

To re-enable the job, just undo the change.

Another better approach is:

With Upstart 1.3, you can make use of an "override file" and the manual
stanza to achieve the same result in a simpler manner:

# echo "manual" >> /etc/init/myjob.override

Note that you could achieve the same effect by doing this:

# echo "manual" >> /etc/init/myjob.conf

However, using the override facility means you can leave the original job
configuration file untouched.

To revert to the original behaviour, either delete or rename the override
file (or remove the manual stanza from your ".conf" file).

manual stanza tell Upstart to ignore the start on/stop on stanzas.
In order to disable SystemV init service:

To enable/disable a service in a particular runlevel, you only need to
create/remove a symbolic link in a particular directory or set of
directories.

This means that you should remove symbolic link in /etc/rc**runlevel**.d/NN**name**  whose  target is script /etc/init.d/name
Another better approach is update-rc.d command that can disable service:
   update-rc.d name disable

You can stop service and start service manually until /etc/init.d/name exists.
To disable service permanently, remove /etc/init.d/name.
Be careful what you do, disable service or job can result an unusable system.
Finally, this is a useful link on how to disable Gnome Session Startup applications and here another on How do I make a program auto-start every time I log in? where you can learn where information are stored and which GUI are available, so I guess you should find out how to disable session application on your system.