Which Bonus Power for an Engineer on Insanity mode?

Question: Which bonus power would be best for an engineer class on an insanity play-through or is it better to take a different class and if so what class/Bonus power should i take? And does anybody have any advice on the best way to approach an Insanity play-through? And what things would make it easier to do? Any advice would be greatly appreciated
Answer: Lets take a look at each bonus power and break it down individually:
Ashley (assuming she's alive):

Inferno Grenade: Not a bad choice as the engineer class doesn't have any grenade powers.  Really useful to flush enemies out from behind cover.
Marksman: Boosts accuracy and fire rate of your weapons, but an engineer is more focused towards powers so not that useful.

James:

Fortification: Provides defense and melee on purge, but slows power recharge by 60% (can be reduced to 30%).  Although survivability is nice, an engineer relies heavily on power spamming so the slowdown on recharge is a big killer.
Carnage: Very high single target damage, can even stagger Atlas mechs.  Pretty useful skill in a pinch, does high armor damage, but incinerate also does high armor damage.

Kaiden (only if he survives virmire):

Barrier: provides defense at the expense of power cooldown just like fortification, not really a good choice imo.
Reave: Insanely useful as the only other way to recover health is to use a med-gel.

Garrus:

Armor Piercing Ammo: Since the engineer doesn't have an ammo ability, and the majority of big and tough enemies in the game high high armor, this is an excellent choice to take.
Proximity mines: Very handy if you can lay down a lot prior to an engagement.  Enemies tend to be more aggressive and mobile on insanity so this isn't a bad choice.

Liara:

Stasis: Holds a single (non armored) target in place for a long time.  Okay ability, not too useful imo.
Warp ammo: One of the best ammo powers imo, grants high damage against everything.

EDI:

Defense Matrix: Same with fortification, reduces power recharge as a trade off for survivability.
Decoy: I never played around with this much, so I can't say either way if its effective or not.

Tali:

Defense Drone: Having an additional target on the battlefield is always handy.  Fully upgraded drones also have a handy AOE effect in chain lightning.  I like this skill a lot.
Energy Drain: Does massive damage to shields and barriers while recharging your own.  This is a great skill to have since it provides survivability without suffering power cooldown penalties.  This is a good alternative to overcharge.

Javik: I don't have him so I'm leaving him out.
In conclusion here are the good ones to consider:
Reave/Energy Drain for survivability
Defense Drone (and possibility decoy) for an additional target
Warp/Piercing ammo for an ammo power
Inferno Grenade/Proximity mine for something different
Comment: Defense Drone cannot be targetted by enemy fire. It's a handy ability, but it's more suited to classes like the Vanguard that will run up in the thick of things. If you want to draw fire, take Decoy.
Comment: You're limited to one active proximity mine, I do believe.
Comment: @RavenDreamer nope, at least not that way on multiplayer.  I spam them all the time everywhere.  However, if they are within a certain distance to each other they'll detonate so you can't place two next to each other.
Comment: @yx. Ah. That'd be my problem, then.
Answer: I fully disagree with Marshal Shepard's assessment or the engineer being too squishy for insanity.  My favorite class is the engineer and I have completed ME2 multiple times on insanity and ME3 once on insanity.
First, the ability to double your squad size with a combat drone and a sentry turret within the first 6 seconds of an engagement is unmatched.  Because the Mass Effect AI forces the enemy to deal with drones first both of those abilities enable you to get inside the enemies decision making cycle and thus influence the battlefield on a major scale.  So while your squadmates are taking advantage of the chaos the engineer just created, the engineer can either assist with target engagements or continue to influence the fight through continual spamming.
Second, incinerate is one of the most powerful and effective powers available.  Not only does it deal massive damage, but it damages every level of protection, including regeneration.  Add to this the "panic" effect and once again the engineer influences the fight by interruption the actions of the enemy.
Third, overload is now more powerful than ever in Mass Effect 3 since warp has been changed to no longer strips barriers, and overload has been changed to strip not only shields, but also barriers.   Now, not only does overload strip valuable protection, but it stuns opponents and overheats weapons.  With these changes to overload in ME3 energy drain is somewhat superfluous.  The engineer now must decide if they would rather have the weapon overheat effect of overload, or the draining effect of energy drain.
Fourth, cryo blast although not damaging allows the engineer to remove enemy numbers from the fight by snap freezing them.  In the sequence of a battle by the time the drone and turret have been on the field long enough to strip shields and barriers the engineer can begin freezing opponents thus providing easy targets for the squad.
Fifth, sabotage is the only power available that will turn the enemy against itself.  Assuming control of a turret, Geth Prime, cannibal or marauders is an extremely effective way of reducing the enemy force while conserving your own.  If done properly, the engineer can add 3 members to the squad; a combat drone, a sentry turret, and a sabotaged enemy.
Sixth, because Mass Effect does not differentiate specific armor types by class, the engineer is able to wear the same level of armor as a soldier.  Add to this the ability to modify armor and select bonus powers and upgrades and an engineer's health and shields will surpass and can rival any member of the squad.
Finally, once again because Mass Effect 3 no longer differentiates specific weapon types to specific classes, the engineer is able to carry a high damage assault rifle such as the Mattock or high capacity sniper rifle such as the Raptor.  Thus the engineer is able to engage and destroy targets at any range and at any point in the combat sequence.
When compared to the most common player strategies of cloak-shoot-repeat, charge-shoot-repeat both which force the player to target a single enemy at a time, the engineer's strategy of drone-turret-overload/incinerate allows the engineer to target 3 opponents within 6 seconds, tying two of those opponents up for prolonged periods.
This analysis, I believe demonstrates not how squishy the engineer is, but rather how powerful and useful the engineer actually can be even on insanity level.
Comment: great post, but the original question is to decide which bonus power to choose, not whether or not an engineer is great.  Very tempting just to give a +1 for effort though.
Comment: Very true and I was going to add that i fully agree with your original post, but i removed it in the final edit because i was specifically addressing and different topic. In fact your assessment is how i determined my engineer's bonus power, which is usually either armor piercing ammo or energy drain. However, I really wanted to address the comment by Marshall Shepard, although we are all entitled to our opinions' I felt an opposing view was necessary.
Comment: yea, that other post isn't an answer either (I flagged it as such) but its still there
Comment: Good point, ironically i was just web surfing doing some ME3 research and found this site.  I joined specifically to address that engineer post.  And like superman, my work here is done ... up, up, and awayyyyyyyy :)
Comment: The question does say "how should I approach an insanity playthrough", I feel this answers that part of the question nicely.
Answer: The best way to tackle Insanity is with a character that's close to level 60 (2nd playthrough after importing from ME2 or 3rd playthrough without importing). Weapons and tactics requiring you to be exposed for long periods of time will be less effective, so a class that relies heavily on powers and high-damage weapons (Sniper rifles, shotguns, heavy pistols) is preferable. Biotic detonations are quite effective, taking Liara and Javik (From Ashes) will let you do a detonation every 3 seconds or so, which is quite nice.
Positioning your squadmates can help quite a bit too, as they will be less likely to charge a bunch of enemies with automatic weapons that way. Speccing a squad member to be a tank (High health, high shields, barriers, forticiation, etc) can also be helpful.
The choice of a bonus power largely depends on how you're going to play. If you wish to go in guns blazing, Barrier, Fortification and Defense Matrix will be useful. If you wish to rely on powers instead, something that fills in a gap in your arsenal is preferred (Such as Energy Drain for Infiltrators, who lack an ability that targets shields).
Answer: the problem with playing Engineer is that you're too squishy for insanity. I'd suggest you made an infiltrator because it has cloaking ability that can get you out trouble, cryo ammo that disable your enemies, incinerate for armored foes, and high dmg with sniper (you can use M-99 saber or chakram launcher if you desire, they both have high dmg and weight less than sniper rifle). Don't bring too many guns, you need the cd reduction. The only thing that lacks on an Infiltrator is ability to remove the enemies' shield/barrier, so i'd suggest you take Energy Drain for your extra ability so you can sustain and deal dmg at the same time. I'd take Liara for disables and the 3rd squadmate is really up to you. With that set-up, I was able to go through insanity mode w/o any real problems, even against kai leng. (energy drain is too nice to pass up on)
Answer: I would go for an ammo power, I know the Engineer is a powers class it's still nice to have damage bonus and backup fire during cooldowns! A defense drone would also be good because you could get an extra 4 allies on the field:

Defense Drone
Combat Drone
Sentry Turret
Sabotaged Enemy
Answer: Defense Matrix is a good option. It can increase tech powers damage and helps to survive in complicated situations. Engineer do not need additional active powers, he already has the strongest combos. Sabotage(+100% damage from tech powers)->Cryo Blast (optional)->Incinerate(if frozen +100% damage+electric combo after Sabotage)->Overload(fire explosion, if chain overload can be multiple explosions). Cerberus troop just can't survive in this hell.
Almost the same we can achieve with Infiltrator + great damage of sniper rife. He only can't make fire explosion (Energy Drain can do it only of enemy has shields), need help of squadmates to finish combo.


How can I view login/logoff times for Windows Server 2008?

Question: I use Windows Server 2008 at my workstation and sometimes work from home. Is there an easy way of viewing the login and logoff times from the event viewer so I can see how many hours I was logged in or simply to find out when I started working? Preferably another application with an easier interface than manually looking at the event viewer, which is cluttered even after filtering out other unrelated events.
Comment: http://serverfault.com/questions/141268/see-what-time-a-user-logged-into-a-windows-box/141275#141275 May be helpful for you.
Answer: As you are no doubt aware, the event logs are anything but easy to read. I suggest you create logon and logoff scripts to record the times into a separate log file.
Answer: Here is a nice explanation for making quite powerful filters:
http://blogs.technet.com/b/askds/archive/2011/09/26/advanced-xml-filtering-in-the-windows-event-viewer.aspx
You can afterwards export the data to excel and work with it.
Answer: Answer for a domain environment.
Install additional account info dll on your dc.  http://www.windowsitpro.com/article/tips/jsi-tip-8045-how-can-i-add-an-additional-account-info-tab-to-the-user-properties-of-active-directory-users-and-computers-.aspx
Very easy to view the info there, but remember account logon info is specific to each DC so make sure to query each of them.
Comment: In 2008 domain there is no need for that FYI, they've added the Attribute Editor tab in ADUC to show the same or similar things. all the properties of an object can be found there.
Answer: You could follow this:
http://teusje.wordpress.com/2012/09/11/windows-server-logging-users-logon-and-logoff-via-powershell/
Eventually you could write the info in one log so that you see the logon/logoff time in the same file. When you logoff you could also extend the powershell script read the log file, search for your last login time, parsing the time and measuring the difference and write it also to the log.


Diagnostics of spatial regression residuals in R

Question:
I fitted multiple spatial regression models - spatial lag model, spatial error model and spatial durbin model. My question is, how do I check the assumption of normality on errors? In classical linear regression, the diagnostics is done on standardized or studentized residuals, but how do I standardize residuals in these spatial models? When I use function "residuals()" to retrieve residuals from the spatial models and do QQplot, they always have this "S" shape. Does it mean the models are wrong?

The same for weighted spatial error model. Which residuals should I use to check the model assumptions?
Answer: There are two reasons for assuming that the residuals are normal. One is the Central Limit Theorem: if your model captures the major causative influences, but there are also many independent minor ones, then the residuals will be normally distributed.
The other, less convincing, argument is that this assumption justifies some efficient solution algorithms which we can run to make a model.
You say your residuals have an "S" shape. That doesn't sound so bad. Does that mean that you can do a non-linear transformation of the problem that will result in normal residuals? e.g. take logs? (Once I got good results using a cotangent - there was a domain reason why that made sense.)
Sometimes the residuals are just nasty, e.g. a Lorenz distribution on one problem I worked on.
Comment: This reads more like comments to the question rather than an answer to it.  Nevertheless, it might be worth noting that the CLT often doesn't apply -- whence the motivation for the question!  Indeed, in many applications variation is multiplicative, implying lognormal conditional distributions.  Also, an s-shaped QQ plot of residuals will not be cured with a logarithmic transformation of the response (or, indeed, with any power transformation).


Canon Digital Photo Professional 4.0 won't "transfer to photoshop"

Question: After editing a raw image in DPP, I am not able to use the "transfer to photoshop" option. All I get is, failed to start photoshop. I am running windows 7 ultimate and PS CS5.1, and Canon DPP 4.0 64bit.
After doing several hours of research on the internet, it appears I need to change something in the registry.  If I do, what are the risks of screwing up...is there a safe way to backup the registry?
Thanks
Sue
Here are the instructions

Open the windows registery by using the "regedit" program (Click Start and in the text box type "regedit").
If the following branch doesn't exist in your registery, create it : [HKEY_LOCAL_MACHINE\SOFTWARE\Wow6432Node\Adobe\Photoshop\12.0]
Inside the "12.0" branch, create a string value named "ApplicationPath" and give it as value the path of Photsoshop 64 bits (C:\Program Files\Adobe\Adobe Photoshop CS6 (64 Bit)). You can do this by right clicking on "12.0" section and then choose New -> String Value
Inside the "12.0" branch, create a string value named "PluginPath" and give it as value the path of Photsoshop 64 bits plugin folder (C:\Program Files\Adobe\Adobe Photoshop CS6 (64 Bit)\Plug-Ins).
Close regedit.
Restart DPP and try the keystroke of ALT-P
Answer: Even though modifying the registry is risky, you can always backup any entry. For that: Open regedit (win + r type regedit in it), search for the registry entry to be edited and at the folder icon, right click then look for "export", if something goes wrong you can always import it again by just double clicking the new file.


What exactly are the reasons for "the road of excess leads to the palace of wisdom?"

Question: Empirical facts seem to support this connection: the Greeks were anything but modest, and among the Greeks, the Athenians were the most extravagant.
I wonder what exactly are the reasons behind this connection.
Answer: What does the phrase have to do with the Greeks? And the Greeks had "Nothing in excess" as a proverb.

Wikipedia says of the phrase (which was written by Blake, as one of the "Proverbs of Hell"),

Unlike that of Milton or Dante, Blake's conception of Hell begins not
  as a place of punishment, but as a source of unrepressed, somewhat
  Dionysian energy, opposed to the authoritarian and regulated
  perception of Heaven.
In the most famous part of the book, Blake reveals the Proverbs of
  Hell. These display a very different kind of wisdom from the Biblical
  Book of Proverbs. The diabolical proverbs are provocative and
  paradoxical.
Blake explains that,

"Without Contraries is no progression. Attraction and Repulsion,
    Reason and Energy, Love and Hate are necessary to Human existence.
    From these contraries spring what the religious call Good & Evil. Good
    is the passive that obeys Reason. Evil is the active springing from
    Energy. Good is Heaven. Evil is Hell."

For what it's worth, to the extent that it's true, the phrase reminds me of the "Middle Way" of Buddhism; i.e. that you might (as the Gautama Buddha himself did, with his early life as a worldly prince followed by  his striving for enlightenment as an ascetic) know extreme (excess) before you know wisdom (sufficiency); e.g. you know "not enough" and "too much" (excess) before you understand "enough".

"There are two extremes, O bhikkhus, which the man who has given up
  the world ought not to follow-the habitual practice, on the one hand,
  of self-indulgence which is unworthy, vain and fit only for the
  worldly-minded and the habitual practice, on the other hand, of
  self-mortification, which is painful, useless and unprofitable.
"Neither abstinence from fish and flesh, nor going naked, nor shaving
  the head, nor wearing matted hair, nor dressing in a rough garment,
  nor covering oneself with dirt, nor sacrificing to Agni, will cleanse
  a man who is not free from delusions. Reading the Vedas, making
  offerings to priests, or sacrifices to the gods, self-mortification by
  heat or cold and many such penances performed for the sake of
  immortality, these do not cleanse the man who is not free from
  delusions. Anger, drunkenness, obstinacy, bigotry, deception, envy,
  self-praise, disparaging others, superciliousness and evil intentions
  constitute uncleanness; not verily the eating of flesh.
"A middle path, O bhikkhus avoiding the two extremes, has been
  discovered by the Tathagata-a path which opens the eyes, and bestows
  understanding, which leads to peace of mind, to the higher wisdom, to
  full enlightenment, to Nirvana! What is that middle path, O bhikkhus,
  avoiding these two extremes, discovered by the Tathagata-that path
  which opens the eyes, and bestows understanding, which leads to peace
  of mind, to the higher wisdom, to full enlightenment, to Nirvana? Let
  me teach you, O bhikkhus, the middle path, which keeps aloof from both
  extremes. By suffering, the emaciated devotee produces confusion and
  sickly thoughts in his mind. Mortification is not conducive even to
  worldly knowledge; how much less to a triumph over the senses!
Comment: Thanks, @ChrisW. Were not philosophy, mathematics, science, theatre, literature and Art just some of the Greek's indulgences?
Answer: Excess do leads to wisdom if used right.
If you are living grand you have more data available to you. Living in a palace you encounter more things and more people than living in a cottage in a village.
Your palace would have population of an entire village living in it out of necessity to have servants to run this large place. You would have an entire other village's population as guards.
You will have more visitors. You can accomodate more guests. You can have large family of your own, like a sheikh, have large extended family living with you permanently.
You can have more friends.
On daily basis you encounter more things and more variety of things. Furniture, clothings, jewellery etc.
Thats half the requirement of wisdom. Have more to ponder on. More data.
Second half is to actually do ponder on them. Being rich you would have more time to think. You can survive with what you have for 100 years if you dont make a penny any more. There are no pressing, urgent needs of survival to keep you busy.
Now, you can use all these resources wrongly. You can indulge in pure pleasure seeking and thus waste it all.


PHP array performance - memory wise

Question: I have an array of size 5 MB, I am passing it to functions to functions (I am not passing it by reference)
foo( $arr );

function foo( $arr ) {
    ....
    bar( $arr );
    ....
}

function bar( $arr ) {
    ....
    test( $arr );
    ....
}

function test( $arr ) {
    ....
    test2( $arr );
    ....
}

PHP passes array values by value (copy of value) by default to functions.
my question is,  if this array value is passed to 100 functions calls, will the PHP consumes 100 x 5 MB = 500 MB of memory ?
How the PHP handles big arrays ( in memory wise ) on function calls?
Comment: You can find out with http://www.php.net/manual/en/function.memory-get-usage.php.
Comment: Couldn't tell ya, but you might want to look into iterators and foreach loops, you can probably have a lot better memory consumption that way.
Answer: Here is a code to test:
<?php

    function testnochanges($arr1){
        foreach($arr1 as $val){
            //
        }
        return $arr1;
    }

    function testwithchanges($arr1){
        $arr1[] = 1;
        return $arr1;
    }

    echo "Stage 0: Mem usage is: " . memory_get_usage() . "
";

      for ($i = 0; $i < 100000; ++$i) {
        $arr[] = rand();
      }

     echo "Stage 1 (Array Created): Mem usage is: " . memory_get_usage() . "
";

     $arrtest1 = testnochanges($arr);
     echo "Stage 2 (Function did NO changes to array): Mem usage is: " . memory_get_usage() . "
";

     $arrtest2 = testwithchanges($arr);
     echo "Stage 3 (Function DID changes to array): Mem usage is: " . memory_get_usage() . "
";

    ?>

and here is a output after i run it:
Stage 0: Mem usage is: 330656
Stage 1 (Array Created): Mem usage is: 8855296
Stage 2 (Function did NO changes to array): Mem usage is: 8855352
Stage 3 (Function DID changes to array): Mem usage is: 14179864

On stage 0 we can see that before array is created PHP is already using some space in memory. After creating first array (Stage 1) we can see a big change in memory usage as expected. But after calling function testnochanges function and creating $arrtest1 on Stage 2, we see that memory usage did not change a lot. It's because  we did no changes to $arr, so $arrtest1 and $arr still are pointing to the same array. But on Stage 3, where we call testwithchanges function, and add an element to $arr PHP performs copy-on-write and returned array which is assigned to $arrtest2 now uses different part of memory and again we see a big grow of memory usage.
Dry conclusion: If you copy array to another array and do not change it, memory usage stays the same as both arrays are pointed to the same one. If you change the array PHP performs copy-on-write and, of course memory usage grows.
Good thing to read: Be wary of garbage collection, part 2.
Comment: Further to this OP, http://blog.golemon.com/2007/01/youre-being-lied-to.html is an explanation of what's going on behind the scenes, if you're interested.
Comment: Interesting ... memory will be allocated only when we change it, good point to learn. Thanks !.
Comment: @SuVeRa I have edited answer with new code and new test to ensure how it exactly works with functions.
Answer: The only way to really find out how your particular use case performs is to complete a benchmark (quick and dirty is fine).  If you are having trouble with performance, you may want to look into SPL.  For example, SplFixedArray can save memory when dealing larger arrays, granted you know the size beforehand.  Also, newer versions of PHP handle garbage collection much better than previous versions, so upgrading may also help.
If you decide to run benchmarks, this will get you started (compares SPL with raw arrays):
https://github.com/elazar/spl-benchmarks

PHP array performance - memory wise


How to make a cylindric wrapping go all arround

Question: I´m using After Effects and the cylindric wrapping tool for Text. The Text has the right size and everything, the only problem is, that the wrapping won´t close all the way. There is always a gap left.
How do I get rid of the gap? (Emphasizing the Text won´t do the trick)
Answer: As I understood from your question, you need to wrap the text (which I didn't see) around the pillar with an animation of your choice.
I did a sample which I think should solve the problem, by creating New Composition, and inside that composition after placing your BG and other layers, you have to think of the pillar in a way that could walk side by side with your wrapping Idea.
Follow my steps to get the same results as mine:
01 - When you draw the pillar, try to draw a perfect tall rectangle and apply (Warp) Effect.
02 - Edit the (Wrap Style) to be "Arc Lower".
03 - Lower the third option value (Bend) to be something around 84 or around.

04 - After applying the effect it will give you something like this.

05 - Create your text layer or animation solid layer and pre-compose it.
 -- I created shapes animation from left to right.

06 - apply (CC Cylinder) effect and change the radius to 69%.
   -apply (Warp) effect and do the same thing that you did with the pillar shape layer or just copy the wrap effec from the pillar and then paste it under CC Cylindar effect.
That should give you something like this:

07 - Turn on the collapse transformations switch on the Text Layer.

08 - Control Your Animation From inside the Text Comp or from outside it, or both.
That's it!
This is my result.

Hope that answers the question
Ahmad Murad


How to use fast pitch

Question: I am making a recipe of cream ale beer, do I use both the fast pitch and the Wyeast when brewing the beer? Does the fast pitch replace the sugar?
Comment: I believe fast pitch is just canned starter wort. The idea being, you add your fast pitch and yeast in a container, let it ferment, decant off the fermented wort, and pitch that the yeast into your beer.
Answer: Fast Pitch is just canned worth with a bit of yeast nutrients. The idea is that you can use this as a pre-sterilised worth to make a starter with your liquid yeast before pitching it into the worth.
It just takes away the trouble of having to use dme and boil it, cool it down, while making a starter.

How to use fast pitch


Where can I find the binaries for arm-wince-pe-gcc?

Question: I am looking for a version of the gcc (C++) compiler targeting the ARM uP and WindowsCE operating system. Thus far I have only been able to locate compilers which either target the ARM uP but produce ELF executables (GNUARM etc) or they do target windows CE but have not been updated since 2003. I believe the exact name of the compiler I am looking for is arm-wince-pe-gcc as mentioned In the GCC documentation but I have no clue how to get hold of a binary. Any/all help will be greatly appreciated.
Answer: I'm using CEGCC from SourceForce: http://cegcc.sourceforge.net/, and so far it works OK. I've managed to build a Windows API application, zlib and libpng, and everything runs just fine on Windows CE 5.0, and the C code you write is the same one you'd write in Visual Studio.
Use the mingw32ce toolchain from there. Build the toolchain yourself, from the latest SVN sources.
I use this under Linux, but it should work under Cygwin as well I'm guessing.
Answer: Build one yourself. GCC is well set up to produce cross-compilers, see the build instructions.
Answer: I found a binary version of the required compiler here: http://sourceforge.net/project/showfiles.php?group_id=173455&package_id=198682 choose
0.51.0/cygwin-cegcc-cegcc-0.51.0-1.tar.gz file for download.


Clingy or something else?

Question: I need an adjective to describe a person who would do anything for another person they love. For instance, they would buy everything for someone they love, they would dance for them, they would do anything whatever is asked even if those things would embarrass them or make them look silly. The best I could find is "clingy", but I'm not sure whether it's correct or not. It's probably similar to "to be a simp", but that's an internet slang, in my view. I'm looking for a proper English word that can be used casually.
Answer: 'Clingy' implies that a person is hopelessly dependent on another. It is really the opposite of being willing to do anything for the other.
If you mean that this willingness to please the other person a positive trait, consider using:

Devoted
Dedicated
Selfless
Self-sacrificing
Unselfish

If you think that this is a negative trait, you might be trying to say they are:

Desperate
Attention-seeking
Simpering
Sentimental
(Too) eager to please
Comment: When I hear people say 'I'm a people-pleaser' I begin to suspect that they have either been in therapy, or have read one or more emotional self-help books.
Comment: If psych jargon is acceptable, "codependent" fits the bill - it's broadly negative and also strongly implies you've been in therapy/reading self-help books.
Comment: @MichaelHarvey Yes, that's why I've gone for adjectives rather than nouns, which would just be labels in this case.
Comment: @Ottie 'Codependent' can mean having an unhealthy attachment to someone, but it can also imply that both have a problem and that there is enabling behaviour, such as a relationship between two alcoholics. I would be wary of using that.

Clingy or something else?


Cloud9 IDE and C Programming

Question: How can I write a C program in the IDE, cloud9? Whenever I start to write its showing errors, I even tried to change the file extension to ".C", but it doesn't work.
Does the cloud9 IDE support C programming?
Answer: Short answer
Yes Cloud9 does support C and C++ programming
Long Answer
Cloud9 has a varying level of support for different programming languages and frameworks.

Cloud9's ACE editor currently supports highlighting for about 60 programming languages including C/C++. The list is growing and you can get the full list from the "View -> Syntax" menu.
The editor has extensive support for JavaScript with error highlighting and code completion. It also has live syntax error checks for CSS, CoffeeScript, PHP, Python, JSON and Lua.
The run menu supports running

JavaScript (node.js)
Python
Ruby
PHP (using apache)

Each project is a unix sandbox with the standard tools like bash, make, gcc, vim, java SDK or perl installed. The terminal in Cloud9 is a full xterm compatible terminal emulator and you can use this to compile and run your C programs.
Cloud9 also has a package manager called c9pm which currently has about 120 packages. These packages include e.g. different versions of python and ruby, mono, lua or groovy.
In case you still need additional tools or libraries you can always download them to your workspace and compile and install them there.

As you see it is hard to draw the line of what is actually supported but usually you will have at least syntax highlighting in the editor and running from the console.
Comment: You may want to actually _mention_ your connection to the IDE since it could be thought that you answer is merely a puff piece.
Answer: It claims support on the web page for "Javascript and Node.js applications as well as HTML, CSS, PHP, Java, Ruby and 23 other languages".
Yet it's very light on regarding details of those other languages. It does state that the editor, ACE, supports many different languages although whether that's natural languages or computer languages it doesn't specify. Additionally, an editor supporting a language is not the same as an IDE supporting it. It makes little sense having syntax coloring for C but no compiler.
Certainly C++ is possible as shown here but the fact that you simply use the editor then switch to a terminal session to compile the code seems to reduce the attractiveness of the so-called "IDE". It doesn't seem to give you anything you can't get from vim/gcc under Linux, or MinGW under Windows. It certainly isn't integrated in the sense that Visual Studio (even Express) or Code::Blocks is.
Regardless, the proper place for this sort of query is most likely on their support page here. I suspect they'd know more about what's supported than anyone here on SO.
Though I wouldn't be hopeful for a response. There's a very similar question asked back on Feb 28 which has still had no response. You have to wonder whether you want to entrust your precious code to a company that takes over four months to answer a simple support query.
In fact, to be brutally honest, I'm not sure I see the value proposition in using such a service. Given that you can get very good local IDEs already (for zero cost), the only possible advantage that springs to mind is collaboration. And, if you're working in a shop that has geographically dispersed developers, they'd probably have a fit if you told them you wanted to store your code where someone outside the company can get at it :-)
I'm not trying to turn you off the idea, just stating that (based on my experience), it doesn't seem as good as a substantial number of other solutions.
Answer: Cloud 9 does support C ( and C++ ) using gcc and g++

gcc --version
(GCC) 4.4.7 20120313 (Red Hat 4.4.7-4)

You can use their integrated editor, but the run button still acts like it trying to execute Javascript, which is the default, and seems to be their the target audience.
They have a fine C hello world example -- http://support.cloud9ide.com/entries/23541348-C-hello-Cloud9
Typically I just maximize the terminal, and run vim ( they have 7.2 installed ), and it works just like any passable unix terminal.  They also have gdb installed, if you need a debugger.
There are comparisons against installed compiler solutions, but that isn't what Cloud9 is competing against.  Their own description is Google Docs for code, and that seems to pretty fairly accurate.  It certainly isn't all things to all people, but it is a pretty amazing service.
With Cloud9 I can write code on my Chromebook without having to install a bunch of stuff to almost make Linux run on it.  This would be a good solution for students, since it would allow them to work in a computer lab without needing any software installed.  I have found that using github and c9, I can easily switch back and forth between c9 while I am remote, and a local setup when I am on a real computer.

Cloud9 IDE and C Programming


Can anyone identify this shower door rubber gasket?

Question: Can anyone identify this rubber seal or recommend an alternative? Its old and mildewed and needs replacing
Comment: Visit a specialty glass dealer — one that caters to the public as opposed to one that is trade only — and ask nicely for their help. You might get a cold shoulder at the first one or two.
Answer: Try searching this Pemko Catalog. I think they are the largest manufacturer of weatherstripping, etc.
https://absupply.net/pdf/PemkoFullCatalog2012.pdf
If you find something close, you can get it (or order it) through your local lumber yard. Amazon has some of the most popular styles, sizes, etc. too.


What software is photographer Diar Kamal showing on his Facebook page and Instagram feed?

Question: Hello every one a few days ago I came by this photographer's photos. He posted some screen shots of a software I want to know the name of the software. Thank You.
Answer: This looks like Scratch, by Assimilate Inc. This is (very pricey) color-grading software used for video, and not normally used for still photography (although it can work with and produce stills).
In fact I think this is just the free Scratch Play, which is a video player with the ability to generate color correction tables to use in the full software. I think that because other images like this one found on the photographer's Facebook page have advertising in the corner, which strongly implies that it is the adware player rather than the full software.
I have no idea why one would want to do this — I don't think the player can actually save any color edits for direct use. It's possible that the photographer is making color adjustments in Scratch Play and then saving them by taking screenshots.


What is this effect (Motion Trails) called and how can i create it?

Question: I'm new to adobe premiere pro and I don't know what this effect called and how to create it.
YouTube
Answer: It's a motion trail. You can use After Effects to create one using the Echo effect. Here's a tutorial that explains how to do it:
Answer: I would call it "Onion Skin" Effect.
I suppose there is some plugin for some software like after effects, premiere, DavinciResolve, or something.
A way to manually do it would be layering copies of the same video, let's say 10 copies and de-synchronize them by a couple of frames incrementally.
Define also incremental or decrimental values for the opacity.


Formal verification on Hardhat

Question: Is there any tool to be able to do formal verification on hardhat projects that's open source?
Answer: Some great open source FV tools are the SMT Checker by the solidity team  (there's a nice introduction thread here) and manticore maintained by Trail of Bits.
For a detailed overview of Formal Verification, you can check out this repo.
Answer: Certora also has a variety of tools to help you with contract security including formal verification: https://demo.certora.com/
Comment: Yeah, sadly I need an open source tool for this specific project

Formal verification on Hardhat


Correct implementation of Memento

Question: With the memento design pattern, is it wrong to have the Caretaker as an aggregate of the Originator?
Answer: Not necessarily. The main purpose behind Memento is that it is possible to deal with different Originators in uniform, transparent way (get Memento, pass it back later to restore state).
The aggregate relation doesn't necessarily prevent that. Different instances of Caretaker might be aggregates of different Originators (although one instance of Caretaker deals with only one instance of Originator) and still get the benefits of transparent state restoration.
Comment: can I store in static variable of class Memento object?
Answer: No, that's fine if it's what works out as appropriate for your situation.  It's not a big leap to understand that the Caretaker's state isn't part of what's preserved in the Memento.

Correct implementation of Memento


How to remove checkboxes from parent rows in Lightning:treeGrid in Aura component and keep them on children rows only

Question: How can I remove the checkboxes on the first column of the TreeGrid for the parent rows and only keep the checkboxes for the children rows?
I've read countless articles and the only thing I found so far is setting the hide-checkbox-column attribute to true in the lightning-tree-grid component, but this removes all the checkboxes.
Any help is much appreciated!
Comment: i dont  think  it would be possible.  you can also  take a look at official  doc.https://developer.salesforce.com/docs/component-library/bundle/lightning-tree-grid/documentation.   you can develop  a custom solution using slds  styling  and your logic.
Comment: @gauravsharma Thank you for the link!! Can you please give me some pointers about implementing my own custom solution? I'm new to salesforce so I have no idea how to do that
Comment: @Dr.Simplisisti have  updated the answer  from high level perspective.  please also  take a look of a basic  lwc  implementation.  https://webcomponents.dev/edit/k97nyPYUViWp2LBAIWXb/src/app.html?p=stories
Answer: To have  a custom logic   for  checkbox, to best of my knowledge  you need to develop  custom treegrid.
from high level perspective  to develop  acustom treegrid  ,   you need to develop  nested  table  structure.
please refer to treegrid  blueprint:
https://www.lightningdesignsystem.com/components/tree-grid/#site-main-content
Create  a nested  table  using  slds design.
use nested template for:each  in lwc each for parent  and child   or aura:iteration   in aura   to show   nested table data.
modify  your nested  json data  containing  parent and child in init  of aura  or  connectecallback of lwc  and add some  custom property  for   your checkbox logic   and  to hide/show   child data.
please also  refer to a very basic  custom implementation in lwc.
https://webcomponents.dev/edit/k97nyPYUViWp2LBAIWXb/src/app.html?p=stories
Comment: Thank you so very much! I really apreciate it! I'll try what you recommended and let you know of the results.
Answer: You can use css to get this done:
.THIS tr[aria-level="1"]  > td[data-col-key-value="0-SELECTABLE_CHECKBOX-0"]{
    visibility:hidden !important;
 }

Might not be the best way to do it, but it worked for me...
Cheers!
Comment: its not working when i tried.please put with example.


safari cannot play audio in wikipedia

Question: The safari in my iPhone 6 can not play audio file in Wikipedia,  for example, the following picture shows a audio file one a Wikipedia page but I cannot play it. what's wrong with it and how to fix it?
Answer: Actually, Wikipedia provided solutions for this, Wikipedia:Media help (audio and video)

It is highly recommended that you use a program which is capable of playing both Vorbis audio and Theora video since these two different media formats are often in the same digital container format, Ogg.
Answer: In Wikipedia create an account and login. Then you can play ogg files. For example this:
https://en.m.wikipedia.org/wiki/File:Cher_-_Dark_Lady.ogg
For other sites I don't have any specific solutions. But obviously Safari supports ogg, at least in iOS 14.2
Answer: Safari does not support playing OGG files. I haven't checked but there are probably apps available that allow you to play OGG files, a simple App Store search of "ogg audio player" should yield some results.
Answer: Safari does not natively support OGG audio files, you need install an OGG plugin. Or just install another web browser on your phone which supports OGG files.
Comment: Thank you, but how to install an OGG on Safari?
Comment: Ogg Drop will encode audio tracks and CD's into vorbis. It also contains a QuickTime component that allows iTunes to play ogg vorbis files. Ogg Drop is entirely free.
Comment: Thanks, it seems Ogg Drop works only on the desktop version, (OS).

safari cannot play audio in wikipedia


Can't remove steam

Question: I'm running Ubuntu 14.04. I tried to install steam from the .deb from the steam website (steam_latest.deb) and this didn't work; I installed later with apt-get install steam (along with the 32 libraries and stuff) and this was successful, but I was left with a huge steam-launcher icon in the unity launcher, that does nothing and says "Invalid UTF-8" as a description, presumably from the first attempt, which was done with the deb through software center. I tried apt-get remove steam, but just got rid of the one that actually worked. Great. Tried to reinstall from deb, and uninstall again, now I have 3 giant ugly useless icons, and no working steam. Wonderful. Any help is appreciated. Thanks in advance!
Comment: Welcome to Ask Ubuntu.  **;-)** For the future, please read [How to install software on Ubuntu if you're a Windows User](http://askubuntu.com/a/575161/344926)
Comment: @cosmoflop12 if this has solved your problem please let us know.
Comment: I'm not sure exactly what solved it, but I think the purge ended up doing it. But it took a reboot before the icons went away. Thanks everyone for the help.
Comment: @cosmoflop12 Great that this solved the problem, please close the question by marking the answer, i.e., which ever solved it.
Answer: You could try doing this sudo apt-get purge steam-launcher and then install steam again.
purge - Purge is identical to remove except that packages are removed and purged. Purge meaning that any configuration files are deleted too.
Let me know if this works or not.
Also try this and see which all directories have steam installed in it dpkg -L steam-launcher
Make sure you have run all this before sudo apt-get update and sudo apt-get upgrade.
Answer: In order to get rid of these thing you need to use autoremove instead of remove so it will be like this
sudo apt-get autoremove steam-launcher

After you remove Steam, you can easily install it back on ur system with the .deb file downloaded from steam official website.
Regards

Can't remove steam


Can all epiphytes be mounted to wood?

Question: I just mounted some staghorn ferns and have been reading that Hoyas can also be mounted. I recently picked up a lipstick plant, and while I can't find any information on whether this genus (or whatever) can be mounted, I'm wondering if it's a safe assumption that as an epiphyte, mounting would be viable.
Comment: Are you asking about hoyas or lipstick plants?
Comment: lipstick plants. but also I'm wondering if mounting epiphytes might be a safe bet in general.
Comment: Some orchids do well on wood ,others do not seem to;  I think you would need to  research each one. I have some "ground" orchids that I doubt would do well.
Answer: So I went ahead and mounted a lipstick plant. It's been almost a week and it seems to be doing alright, with some noticeable growth since mounting. will update in a few months in case anyone's interested

Can all epiphytes be mounted to wood?


What is this tree?

Question: What is this tree? Located in Northeast Ohio...
Comment: Can you add any more information like, is it deciduous? does if flower?
Comment: Yes, it is deciduous. I don't remember if it flowers. These are photos from last year and right now it is too early for new leaves/flowers.
Answer: I think it's probably Acer negundo, common name Box Elder - that variety of maple has variably shaped leaf arrangements, as well as variation in individual leaves. I can't see how the leaves are arranged in the picture, but the shape of some of them would indicate one of the Acers (not all have the classic fan shaped, five pointed leaf), and the fact the keys or samaras are held in pairs on long stems in clusters rather than in a single, long raceme fits with Acer negundo. Image of leaves, showing a typical arrangement, plus images of flowers, shoots and bark (which we can't see detail of in your picture) below for you to compare
https://www.minnesotawildflowers.info/tree/boxelder
Comment: @LaurentDuval - yep, found a reference to Ashleaf Maple on the Hainault Forestry Commission site in the UK - its a less common and little used name, secondary to Box Elder. I find it confusing its called Box Elder, never made sense to me, never mind Ashleaf Maple...and why I loathe common names, you never know what anyone's talking about because it depends where they come from which common name they use.
Comment: Thanks. Once the leaves grow back I'll take a look at how they're arranged and look for buds/flowers.
Comment: @Bamboo Your answer makes more sense to me. As I am more familiar with tree anmes in english, it seems that this one is also called ash-leaved maple
Comment: @LaurentDuval - not in the UK its not! Common name here is actually Box Elder... ash leaved maple sounds more like something the States would use as a name - and its not even 'ash leaved' either, ash leaves are composite with 7,9 or more leaflets to a leaf, so that name doesn't make any sense to me at all, apart from the 'maple' bit, you sure its given that name elsewhere? that said, I'm not 100% on this ID, need to see a single branch with leaves on and get a close look at the bark...
Comment: @Bamboo "ash-leaved maple, and maple ash are its most common names in the United States; in Britain and Ireland it is also known as ashleaf maple." from the wiki page. Not my knowledge ;)
Comment: @LaurentDuval7 Aye, that's what Wiki says - but then Wiki says all sorts of things...! If I can find another, horticultural source which says the term ash maple is used in the UK, I'll let you know...
Answer: A first guess, based on the samaras (known as "keys" or "helicopter seeds") and the lance-shaped leaves, (very) slightly toothed on edges: an ash tree?

What is this tree?


Problem with trigonometric equations

Question: In a given question about a trigonometric proof I was trying to solve, I got in
$$ \tan(x - π/4) = -\, 1 $$
then I solved it just like any other trig equation, but, after I managed to finish the demonstration, I get back to that equation and tried a different approach, by applying the inverse function in both sides of the equation:
$$ \arctan(\tan(x - π/4)) = \arctan(-\, 1) = -\,π/4. $$
But, after analysing both sides, I realized I've got an absurd after considering that $$ \arctan(-\, 1) = -\,π/4 $$ since, to succeed in my proof, I had to consider that $$ \arctan(-\, 1) = 3π/4.$$
My question is, how to solve simple trigonometric equations, like the one I posted above, by applying the inverse function without getting an absurd?
Just to mention, the $$ x $$ in the tangent argument is equal to $$ \arctan(2) + \arctan(3), $$hence it satisfies the arctan condition.
Comment: Note that arctan(tan(x-pi/4)) is periodic.
Answer: As there are infinitely many values of $x$ having the same value of $\tan x$, we usually take the principal value only when using the $\arctan$ function. That is, $\displaystyle -\frac{\pi}{2}<\arctan k<\frac{\pi}{2}$. So, $\displaystyle \arctan(-1)=-\frac{\pi}{4}$ and $\displaystyle \frac{3\pi}{4}=\arctan(-1)+\pi$.
For $\displaystyle \tan\left(x-\frac{\pi}{4}\right)=-1$, $\displaystyle x-\frac{\pi}{4}=n\pi+\arctan(-1)=n\pi-\frac{\pi}{4}$ and hence $x=n\pi$.  The value of $x$ may be further restricted by the conditions given in your original problem.
For the problem $x=\arctan(2)+\arctan(3)$, let $u=\arctan(2)$ and $v=\arctan(3)$. Then $\displaystyle \frac{\pi}{4}<u<v<\frac{\pi}{2}$. Since $x=u+v$, $\displaystyle \frac{\pi}{2}<x<\pi$.
$$\tan x=\tan(u+v)=\frac{\tan u+\tan v}{1-\tan u\tan v}=\frac{2+3}{1-(2)(3)}=-1$$
$$x=n\pi+\arctan(-1)=n\pi-\frac{\pi}{4}$$
So, $\displaystyle x=\pi-\frac{\pi}{4}=\frac{3\pi}{4}$.
Answer: $$\tan\left(x-\dfrac\pi4\right)=-1\implies x-\dfrac\pi4=m\pi+\arctan(-1)$$
where $m$ is any integer
Comment: Nope. Not correct. Rather use generwl value of arctan(tan(x-pi/4)) which is periodic. Arctan is not!!

Problem with trigonometric equations


What do the getUTC* methods on the date object do?

Question: What does it mean when you get or create a date in UTC format in JavaScript?
Answer: A date represents a specific point in time.  This point in time will be called differently in different places.  As I write this, it's 00:27 on Tuesday in Germany, 23:27 on Monday in the UK and 18:27 on Monday in New York.
To take an example method: getDay returns the day of the week in the local timezone.  Right now, for a user in Germany, it would return 2.  For a user in the UK or US, it would return 1.  In an hour's time, it will return 2 for the user in the UK (because it will then be 00:27 on Tuesday there).
The ..UTC.. methods deal with the representation of the time in UTC (also known as GMT).  In winter, this is the same timezone as the UK, in summer it's an hour behind the time in the UK.
It's summer as I write this.  getUTCDay will return 1 (Monday), getUTCHours will return 22, getUTCMinutes will return 27.  So it's 22:27 on Monday in the UTC timezone.  Whereas the plain get... functions will return different values depending on where the user is, the getUTC.. functions will return those same values no matter where the user is.
Answer: getUTC is for converting times to Coordinated Universal Time (UTC, the acronym is ordered differently than what it stands for) which is the standard time based on the time in Greenwich, London.
The universal time is calculated using a time offset (in minutes when in JavaScript.) This offset is based on the time zone configured on the client browser's operating system.
If you plan on storing dates for users in multiple time zones, this is what you should use.
Answer: Further to Dan's remark about the acronym being different to what it stands for is a good reason: UTC Abbreviation on Wikipedia


How do I calculate the resistance of a copper bar?

Question: I'm trying to calculate the resistance of a copper bar in a DC current, but I'm not sure how to do it. The only things I've seen online calculate the resistance of a wire and ask for its gauge, but a bar is not a wire and it doesn't have a gauge. It's a rectangular prism shape and its dimensions are 1.3cm x 2.5cm x 30cm. You don't have to do the math for me I just would like a formula for getting the resistance.
Comment: https://en.wikipedia.org/wiki/Electrical_resistivity_and_conductivity
Comment: So resistance = resistivity * length / cross section
Comment: Thanks, that really helps. Don't know why I didn't notice that when I last looked on the wikipedia page.
Answer: While you can look up the resistivity of copper on wikipedia or Kaye & Laby, you'll find that the answer is given in units of 10^-8/m. I don't know about you, but I always miscount powers of 10 when using that sort of unit. Instead I commit the following to memory
1 metre of \$1mm^2\$ copper wire has a resistance of 17 \$m\Omega\$ (roughly)
If you can't remember that resistance is proportional to length, and inversely proportional to area, then just think series resistors, or parallel resistors.
10m of wire would have 10x the resistance, it's like ten 1m lengths in series.
If the wire is 4mm2, it will have 1/4 the resistance, because it's like four 1m lengths in parallel.
Copper, like all pure metals, has a fairly strong temperature coefficient of resistance, which is why I've only given the resistivity to 2 significant figures. The tempco is 0.4% per degree C, or a whopping 10% change for 25 degree change in temperature. It can be useful to remember that when you want to estimate the temperature rise of (say) transformer windings, just measure their resistance cold, and again when hot.
Comment: +1 For the transformer temperature measurement trick.
Comment: @KalleMP does that +1 mean you're going to give me an upvote ;-)
Comment: Sure, I forgot or missed the button. Your mnemonic is also something handy to keep in mind when out in the field, it gives a way to sanity test calculation or table results.
Answer: R= \$\frac{\rho L}{A}\$ where L is length, A is cross-sectional area and \$\rho\$ is resistivity.
Take care to use compatible units(!).
\$\rho\$ is a function of temperature. Over a reasonable range, \$\rho\$ of most  elemental metals is approximately proportional to absolute temperature. At very cold temperatures, weird things happen, some metals (lead, for example) see their resistivity suddenly drop to zero and other metals such as copper level off at a value that is strongly indicative of their purity.. the ratio of that to the room temperature resistivity is called RRR = Residual Resistance Ratio.
Comment: I would also add that the formula above assumes that the point of contacts at the extremes of the bar are 'ideal', so that the current density is uniform across the bar section. If this is not true, the becomes higher.
Comment: Does the work history of the material affect \$\rho\$ for  bar stock like it does rolled sheets? (I mean, of course it does, but maybe bar stock is all sold nicely annealed)
Comment: @ThePhoton I think it does, I have slightly different numbers for annealed copper and regular copper. But only slightly.
Comment: Little tip that I recently learned... use `\displaystyle THEN YOUR EQUATION` and it makes your fractions much larger. You can see the results on my answer.
Comment: @SpehroPefhany You're welcome! :) works for integrals too... Practically anything that you want larger, you can use `\displaystyle`
Answer: There are variants of Ohm's Law that are not your typical \$V=IR\$. Henceforth, Georg Ohm has also made some important discoveries of how to measure the resistance of a particular object. For instance, your copper bar (bar is a little ambiguous but I'm assuming you're talking about an ingot or something).
There's a concept called "surface current" that brings your typical line current that travels in 2-D space into a 3-D space. This is noted as:
\$J=I/S\$, where \$J\$ is your surface current, \$I\$ is your line current, and \$S\$ is the surface area of your object. But if you were to bring the current into 3-D space, you also have to bring the voltage into 3-D space. Therefore, we have to utilize the electric field noted as \$E\$. We can make a relationship between the surface current and electric field as:
\$J=\sigma E\$ where, \$\sigma\$ is the conductivity of copper.
You may also find \$E\$ by another relationship known as "Poisson's Equation".
\$E=-\nabla V\$, where \$\nabla\$ is the gradient operator and \$V\$ is your electric potential.
Once you find your electric potential, you are ready to solve the problem... and now it's pretty straightforward. Now you just have to solve for \$R\$... which is easy. Sphero gave you equation already...
\$ \displaystyle R=\frac{\rho \ell}{A}\$
But.... if you weren't given \$\rho\$:
\$\displaystyle V= R\iint_{S}I\cdot dS \rightarrow \boxed{R=\frac{V}{\iint_{S}I\cdot dS}}\$

So KingDuken? Why did you give me all of these equations if all I was asking for was just the resistance?

Good question! I wanted to give you the 3-D insight of resistance :)
EDIT: You know, I just saw your profile and I saw that you were 16 years old. So perhaps using an equation that involves an understanding of multivariate calculus is perhaps not the best way to answer your question... Not saying that a 16-year-old wouldn't understand but there's not a lot of teenagers who not have taken their third semester of Calculus. Let me give you a more acceptable formula:
\$ \displaystyle R=\frac{V}{I\times WHL}\$, where \$W,H,L\$ are the width, height, and length of your copper prism.
Comment: Great answer. I wanted to know how the 3d nature of a copper brick affects the resistance.


Torah approach to getting out of inappropriate feelings/thoughts

Question: What is the Torah approach to stop yourself from feeling sexually aroused in the moment? Anything from the mussar experts?
Comment: very similar: https://judaism.stackexchange.com/q/16734/170
Answer: Berachot 5a:

אָמַר רַבִּי לֵוִי בַּר חָמָא, אָמַר רַבִּי שִׁמְעוֹן בֶּן לָקִישׁ: לְעוֹלָם יַרְגִּיז אָדָם יֵצֶר טוֹב עַל יֵצֶר הָרַע, שֶׁנֶּאֱמַר: ״רִגְזוּ וְאַל תֶּחֱטָאוּ״ אִם נִצְּחוֹ — מוּטָב, וְאִם לָאו — יַעֲסוֹק בַּתּוֹרָה, שֶׁנֶּאֱמַר: ״אִמְרוּ בִלְבַבְכֶם״. אִם נִצְּחוֹ — מוּטָב, וְאִם לָאו — יִקְרָא קְרִיאַת שְׁמַע, שֶׁנֶּאֱמַר: ״עַל מִשְׁכַּבְכֶם״. אִם נִצְּחוֹ — מוּטָב, וְאִם לָאו — יִזְכּוֹר לוֹ יוֹם הַמִּיתָה, שֶׁנֶּאֱמַר: ״וְדֹמּוּ סֶלָה״.
Rabbi Levi bar Ḥama said that Rabbi Shimon ben Lakish said: One should always incite his good inclination against his evil inclination, i.e., that one must constantly struggle so that his evil inclination does not lead him to transgression, as it is stated: "Tremble, and do not sin."
If one succeeds and subdues his evil inclination, excellent, but if he does not succeed in subduing it, he should study Torah, as alluded to in the verse: "Say to your heart."
If he subdues his evil inclination, excellent; if not, he should recite Shema, which contains the acceptance of the yoke of God, and the concept of reward and punishment, as it is stated in the verse: "Upon your bed," which alludes to Shema, where it says: "When you lie down."
If he subdues his evil inclination, excellent; if not, he should remind himself of the day of death, whose silence is alluded to in the continuation of the verse: "And be still, Selah."
Answer: The Talmud in Kiddushin 30b states:

תנא דבי ר' ישמעאל בני אם פגע בך מנוול זה משכהו לבית המדרש אם אבן הוא נימוח ואם ברזל הוא מתפוצץ שנאמר הלא כה דברי כאש נאם ה' וכפטיש יפוצץ סלע אם אבן הוא נימוח שנאמר הוי כל צמא לכו למים ואומר אבנים שחקו מים
The School of R. Ishmael taught: My son, if this repulsive [wretch] assail thee, lead him to the
schoolhouse: if he is of stone, he will dissolve; if iron, he will shiver [into fragments], for it is said:
Is not my word like as fire? saith the Lord,' and like a hammer that breaketh the rock in pieces? If
he is of stone, he will dissolve, for it is written: Ho, everyone that thirsteth, come ye to the waters;
and it is said: The waters wear the stones.
(Soncino translation)

Rashi explains מנוול as:

יצר הרע מתגרה בך
The Evil Inclination inciting you.

Similarly, Rambam in Hilchot Issurei Biah 22:21 writes:

וכן ינהוג להתרחק מן השחוק ומן השכרות ומדברי עגבים שאלו גורמין גדולים והם מעלות של עריות ולא ישב בלא אשה שמנהג זה גורם לטהרה יתירה גדולה מכל זאת אמרו יפנה עצמו ומחשבתו לדברי תורה וירחיב דעתו בחכמה שאין מחשבת עריות מתגברת אלא בלב פנוי מן החכמה ובחכמה הוא אומר אילת אהבים ויעלת חן דדיה ירווך בכל עת באהבתה תשגה תמיד
Similarly, a person should distance himself from levity, intoxication, and flirtation, for they are great precipitators and steps [leading] to forbidden relations.
A man should not live without a wife, for this practice leads to great purity. And [our Sages gave] even greater [advice], saying: "A person should always turn himself and his thoughts to the words of the Torah and expand his knowledge in wisdom, for the thoughts of forbidden relations grow strong solely in a heart which is empty of wisdom." And in [Solomon's words of] wisdom [Proverbs 5:19], it is written: "It is a beloved hind, arousing favor. Her breasts will satisfy you at all times. You shall be obsessed with her love."
(Touger translation)
Comment: It is perhaps clumsily worded (in the Hebrew) but it means that the practice of not living without a wife leads to purity.
Comment: Not sure if it's intended or a mistake, but "a man should not live without a wife, for this practice leads to great purity" (the first sentence of the last paragraph of the last quote)? Shouldn't it be "impurity"?
Comment: Aah, so the "for this practice leads to great purity" part is related to "live with a wife" and not "live without a wife". Got it.
Answer: The Baal Hatanya in Chapters 28-29 of Tanya instructs that if foreign thoughts are distracting someone during lay activities (not prayer or learning etc.) he should  remove his mind entirely from those subjects (and instead control his mind to think about other things and especially Torah) and be joyous that he has the chance to engage in the mitzvah of לא תתורו וכו, not following his desires.
And if the thoughts are being aroused at times of prayer or learning he should increase his efforts in focusing knowing that the power of his prayer/learning are the cause for his yetzer (inclination) to work so hard to distract him!
For a translation of these chapters see https://www.chabad.org/1058817.
Answer: The Yetzer Hara unfortunately is a powerful thing and the challenge is how to combat it effectively. By way of introduction, it is worth noting what Shlomo Hamelech says in Koheles 10:4:

אִם־ר֤וּחַ הַמּוֹשֵׁל֙ תַּעֲלֶ֣ה עָלֶ֔יךָ מְקוֹמְךָ֖ אַל־תַּנַּ֑ח כִּ֣י מַרְפֵּ֔א יַנִּ֖יחַ חֲטָאִ֥ים גְּדוֹלִֽים׃
If the spirit of the ruler rises up against you, don't give up your post; for slackening will make possible great sins.

in the book 'Pathways to Personal Growth'(Feldheim) p.121 it writes:

"The "ruler" is the yetzer hara. There are times when it "rises up against you", and all your progress seems to come to a halt and your mind becomes obessessed with alien thoughts. Your orders at such times are; "Do not abandon your place!" Despite everything. Do not abandon that which makes you into a human being - hang onto your status of "chooser" and "doer" (cf. the Targum)"

So the first point is to not let the moment slip. One should put defences in place to help fight against the yetzer hara. This will help deal with the situation to help effectively fight the urge which will build resilience if the urge returns in the future.
Indeed the Sefer HaChinuch 188 writes how no person is impervious to the Yetzer hara and thus we need 'fences' in place to spare us from falling.
Approach 1 - Torah
The Gemara in Kiddushin 30b writes:

כך הקב"ה אמר להם לישראל בני בראתי יצר הרע ובראתי לו תורה תבלין ואם אתם עוסקים בתורה אין אתם נמסרים בידו שנאמר (בראשית ד, ז) הלא אם תטיב שאת
So too the Holy One, Blessed be He, said to Israel: My children, I created an evil inclination, which is the wound, and I created Torah as its antidote. If you are engaged in Torah study you will not be given over into the hand of the evil inclination, as it is stated: "If you do well, shall it not be lifted up?" (Genesis 4:7). i.e. One who engages in Torah study lifts himself above the evil inclination. (Sefaria translation)

Approach 2 - Prayer
The Chazon Ish (Kovetz Igros Chazon Ish, cheilek alef, letter #2 - apologies I can't find it online) writes:

""Prayer is a staff of strength in the hand of every man." Prayer has the power to keep you at your present level in spirituality and in the end it will enable you to carry on with your ambitions."

Approach 3 - Treat the Yetzer Hara with contempt
A final method is to train our minds to think of the Yetzer Hara with a sense of disdain. Yosef HaTzaddik is a famous example of someone who was tempted but succeeded against the lure of his Yetzer Hara. In Bava Basra 109b we're told that Yosef was "פטפט ביצרו" - that "he battled with his Yetzer". Similarly the Gemara in Gittin 57a this same expression is employed to describe a man who showed a great deal of control - "שפטפט ביצרו יותר מיוסף". Rashi over there explains this to mean that the way he was able to overcome the experience was "זלזל ביצרו", i.e. he treated it with disdain.
In Pathways to Personal Growth (pp.146-47) it writes effectively:

"The first step to overcoming the yeitzer is to treat it with disdain, to demote it from its position of command and to put it in its proper place: "Trua, I have a desire for such and such a sin. But this is by no means my entire world or my reason for living! It is merely  a marginal craving of little value that can be ignored with little difficulty. Considering the harm it will cause it would be insane to give in." In this manner Yosef deflated his Yeitzer". One must put his desires in perspective. The urge to commit a transgression seems overwhelming only if a person attributes too much significance to his desires. A little reflection is all that is necessary to put the yeitzer in its place and to realize that the fantasy image it has painted is in conflict with the reality. Then it will simply melt away and evaporate."
Answer: The Aley Shor (vol 1 page 41) offers that there is nothing greater to stave off the desires that immersing oneself in learning gemorah with rashi and tosefos with hasmadah (diligence). I wish you much success in succeeding in this matter. If your hebrew is good, read his whole piece on this topic from pages 39-41. It helps even if one isn't so successful with this.
Comment: BTW, are you aware of this site (https://guardyoureyes.com/solutions)?


Shooting in Manual

Question: If I set my camera (canon 7d) to manual and the speedlight (600ex) to ETTL, shouldn't the flash put out the necessary power to expose the image?
Comment: What mode are you shooting in? Canons have significantly different behaviour depending on mode.
Comment: Is it not doing so?  What problem are you experiencing?
Answer: If the flash has enough power to properly expose the scene it should. But if your manual settings require more light from the flash than it can provide it will be unable to do so.
Additionally:

Insure that the shutter speed is at or below your camera's flash sync speed so that both shutter curtains are completely open at the time the flash fires.
Insure that there are no objects in the foreground that will cause the camera to reduce power to prevent blowing out the foreground objects. Things that are closer to the camera will be much brighter than things much further away. If the camera sets flash power based on near objects then far areas of the scene will be dark.
Account for any modifiers you place between the flash and scene. This would include bouncing the flash off another surface. Any modifiers will reduce flash power to one degree or another. The more the modifier reduces flash power, the more power you need the flash to output to provide the same amount of light on the subject. If your flash can not provide enough light to overcome the amount lost via the modifier, then the scene will be underexposed.
In cases were the flash is not bright enough at maximum power you can either increase the ISO sensitivity setting or open up the aperture (lower f-number). Changing shutter speed will not affect flash power since the duration of the flash is shorter than the camera's flash sync speed.

Shooting in Manual


Can a student ID containing an NFC chip be cloned?

Question: The head of our IT department and Networking class in my college has given me and another student a challenge; he told us that if we could clone the  NFC tags in our student ID's used to sign in on time, he would give one of us unlimited access to the colour printers for a year. His main motto that he always talks about though is encouraging students to learn through experimentation regardless of whether the students ideas will work or not. He wants us to experience failure as well as success through our own attempts.
I'm  a bit skeptical as to whether it will work because I've read forums online that say this a futile attempt because no reputable academic institution or business would leave their NFC tags unprotected and completely vulnerable to complete cloning.
From scanning the card with my Android phone, I see that it uses a Mifare Classic 1k tag.

Does anyone have an idea how to replicate it? There are some cheap tags on eBay but I wonder if  I should bother if it's not even possible to clone it.
Comment: "...no reputable academic institution or business would leave their NFC tags unprotected and completely vulnerable to complete cloning."  Anybody who writes something like that needs to go poke around the real world for a few hours.
Comment: Totally unrelated: I'm surprised the ability to make *hard copy* (ick) is seen as a reward in this day and age, but I'm out of touch with modern campus realities.
Comment: If you read @Hector answer and source reference, you will notice `NXP is officially recommending to migrate away from MIFARE Classic based systems`
Comment: @ToddWilcox we're talking about unlimited color posters for beer bashes and keg parties.
Comment: If I was you, I'd make sure to get some indication in writing that the head of IT has **authorized** you to try this. If you don't already, I would email them with something like: "We have made some progress researching your challenge  If you are still happy we are ready to trying a physical copy. If so do you have a blank card we can use?" If you don't get an email back (e.g., only gets back to you in person) then tread very carefully... Other wise have fun being *authorized* to break some things! Document everything carefully for when the sh*t hits the fan
Comment: Only time I ever printed anything at University (2010-2014) was for paper submissions (still depressingly common) or for revision purposes (scribbling and circling all over the material I always found useful). That and free black and white printing came in useful for non-uni purposes like boarding passes...
Still. Our departments goto bribes were beer and pizza.
Comment: Can I point out that when your professor said they wanted you to learn through experimentation, their idea of experimentation probably wasn't "post it to SE and do what they told you" :P
Comment: Not sure whether it helps or whether you even want to try something in this direction, but the easiest way to get a duplicate card may be to indicate to the service desk that you need a replacement ;-)
Comment: We had a task in labs set by an eccentric lecturer to crack and try to clone our ID cards. You should be able to crack the crypto, since Mifare Classic is vulnerable to various attacks (my old uni used it too). Besides this, you'll probably also need to clone the ID (door locks often just check the ID), which might be a bit more involved - cards from reputable sources don't let you modify the ID. However, when I did the module a few years back, Chinese cards with modifiable ID fields had started to appear on the market. I don't know if these are now more common.
Comment: If you have an arduino lying around you could get a MIFARE read/write board. That should be able to clone MIFARE classic cards.
Comment: Look at a device called a Proxmark. It's probably (okay, is) overkill for this specific purpose, but it is pretty good at attacking most kinds of proximity cards. There are, of course, more open source and cheaper alternatives as well.
Comment: http://tech.mit.edu/V128/N30/subway/Defcon_Presentation.pdf
Awwwww yesssss.... But I suspect that if you manage to put together someting showing such skills you`ll get more than free printing....
Comment: [Michael Roland](https://stackoverflow.com/users/2425802/michael-roland) must be happy!
Comment: Wants us to experience failure as well as success through our own attempts -- gets posted on stackexchange within the hour
Comment: Researching on SE seems like an intelligent thing to do, and makes you more employable. Better than thrashing around, wasting time and resources.
BTW, maybe the Head of IT is hoping you succeed, so he can go to the next budget meeting with a request for the more expensive, more secure NFC tags he has been after ;-)  (But, I agree, with Darcy Thomas: first get some proof you've been authorized to try and hack...)
Answer: Many NFC enabled smartphones can write to these cards with an app like MifareClassicTool. However I've found several phones seem to be able to do it when in reality trying to write to Sector-0 bricks the card. It may be worth testing one or two cards and if it doesn't work buy a dedicated USB writer.
First of all a huge number of Mifare Classic Systems only use the ID on the card. This is stored in Sector-0 which is theoretically read only. Of course plenty of online sources will happily sell you cards where this is writable. Writing to the cards themselves is trivial.
The encryption on the cards has also been broken and again can be trivially cracked on a smartphone, as seen on Wikipedia: Security of MIFARE Classic, MIFARE DESFire and MIFARE Ultralight. My university used the same cards. As did an Oracle facility I used to work at…
Comment: *"when in reality trying to write to Sector-0 bricks the card"* That sounds like a great denial of service attack on someone's wallet.
Comment: @Luc - Only works on cards with a writable Sector-0. I imagine there is a bug in the driver which hasn't been identified/fixed because its not a legal action. How it ends up bricking the card altogether is beyond me. Might just leave it in a dodgy state that led my reading software to barf.
Comment: @jpmc26: Securing Oracle access has been an issue since the [6th century BC](https://en.wikipedia.org/wiki/First_Sacred_War) ;)
Comment: Ah, Oracle... stuck in the 20th century as always.
Answer: I have recently cloned a Mifare Classic tag. The scan you have there indicates there is no information stored on your tags, apart from in the first sector. This isn't readable by that app because it does not use the default key.
I suggest you first try it with Mifare Classic Tool first, using the extended keys file. There are some common keys there but your tag may use a different one.
If that doesn't work, you will need MFOC or MFCUK with a dedicated reader, or a modified version of Mifare Classic Tool (google it) with your phone to attack the card. It can take upwards of 8 hours with a dedicated (USB / UART / SPI etc. I use a Raspberry Pi with a reader connected by SPI) reader, and even longer with Mifare Classic Tool.
You can then use the above tools to make a dump of the tag, providing you obtain the key.
If there is only data stored in the top row of sector 0 (not including the bottom row), this means the readers only look at the ID of the card. If your phone is rooted, you can then use this app to emulate a card (the ID is the first 4 bytes of sector 0). I have not tested this personally as my phone is not rooted.
Almost all Mifare Classic tags do not allow you to write to sector 0 (where the unique ID is stored), so that the ID can be used for security purposes. However, you can buy some tags (on eBay for example) that do allow you to write to sector 0.
Some of them will let you write them with Mifare Classic Tool, but others won't. This is because they require a special unlock command that is blocked on phones. You will need a dedicated reader (PN532 chipset works well) to write to them and nfc-tools, which you will probably have to compile yourself, but there are guides on how to do this.
Answer: If it is Mifare Classic, that should really not be hard.
The general attack on Mifare's broken cryptosystem has been around since 2007. Have a look at this if you want: BlackHat Talk Slides
This is indeed most likely easily possible. There are plenty of tutorials about this. Just remember: if your ID/whatever is not stored in the data section but only in Block 0 (the card's ID), this is not writable on most of the cards. There are Chinese models (as far as I know) that allow writing to Block 0. If your college just uses the card's ID and does everything else internally (like on a DB basis), you will need such a card.
See also: "How To Crack Mifare Classic Cards"
Answer: I've actually tried a similar thing at my old school, and after months of research, this is what I found:

Write to sector 0 and hope for the best, maybe it's just the ID that's important.
MFCUK, never got around to trying it myself, but if I recall correctly, it will use the security flaw of the classic and figure out the key.
Brute force, the Mifare Classic Tool, have a extended version of the app, that you'll have to download over github, but let's face it, you're probably not going to have much luck with this option...


Local Bubble in space

Question: Is the Local Bubble alone in space or is there another bubble similar to the Local Bubble in space, i.e., do we live in a special place or is this a more general phenomenon?
Comment: Perhaps you are unclear about what the "local bubble" is.  If you edited to describe what you understand "local bubble" to mean, that would clarify the question
Answer: The "local bubble" is a region of the galaxy where the density of interstellar gas is lower than average. It has about 50 thousand atoms per cubic metre, compared with 500 thousand averaged over the whole of the milky way.  It was probably formed by one or more supernova explosions (10-20 million years ago) physically pushing gas away.
There are many such bubbles all over the galaxy, carved out by supernova and other energetic objects. See https://en.wikipedia.org/wiki/Superbubble

Local Bubble in space


The use of italics

Question: I know it's about style and you like to close such questions (don't), but what are some general recommendations concerning the use of italics? More specifically, what proper nouns should I italicize? It can be applied to the names of publications but not to the names of government agencies. It's all I've noticed. What else?
Comment: The 'name of a publication' is a **title** - these are often italicised. The name of a government agency is a proper noun - no need to italicise.
Comment: Different organizations have different style guides with different rules; there is no one "right" answer to this question. Anecdotally, I tend to see "long form" fiction titles italicised (e.g., novels, anthologies/collections, feature films, television series), but "short form" titles in quotes (e.g., short stories, television episodes in a series). Beyond that, there is definite variation; for example, I've seen different sources make references to games in italics (_Monopoly_), quoted ("Monopoly"), bold (**Monopoly**), or just plain text (Monopoly).
Comment: @KateBunting  I slightly disagree with the second part of your comment, ANY complex name (as well as simple names like Monopoly) will sometimes require (though not always get) suitable emphasis to make it readable. I don't see that A Gov Agency is any different to say: The Guardian in this regard. Initial Capitals is a more common method than italics, but the principle is the same.  Scholarly publications typically have complex (and different) rules for citations in their footnotes, using italics, underlines and more.
Answer: As you say, depending on where it is written, certain style-guides will apply, and will differ from each other.
On a more general level, the rule is to do whatever is necessary - Monopoly (the name) for example is pretty well known, and the use of an initial capital clearly sets it apart from the word monopoly. A good example of when 'random' styling is helpful, is when referring to a book or a song in full, where you need to include both title and author/singer. As a simple label  Songname by Well Known Singer  may be fine, but when embedded in a longer discussion, it may be useful to say: Well Known Singer's Songname,  or similar.

The use of italics


Unknown network file on my IMac

Question: I have an unknown network file on my iMac, it appears in the sidebar of Finder, under 'Shared'.  It is called hp3464a93ca02a.  What is this and can I delete it if it is unnecessary?  It has been present for over a year, maybe two and I can attribute no ill effects to it; seems benign, perhaps even helpful.  Just wondering...
Comment: Are you on a network which has an HP device on it, such as another computer, networked printer, etc? That name would seem very much like a vendor (HP) + its MAC (physical) address (34-64-A9-3C-A0-2A) which is sharing services across the network.
Answer: I've got a very similar name in my Finder sidebar as well.
It's an HP product (mine's a printer) that is on your local network that has been setup to be accessible over the network. It disappears when the printer is not powered on.
As "smoooosher" said, its name is identical to the MAC address of the device.

Unknown network file on my IMac


Do I need to keep all treasures?

Question: In Legend of Grimrock I've found some treasures, however they are occupying space in my inventory and adding weight to the carrying limit. Do I need to keep all of them with me for some reason or can I just leave them behind?
Answer: No, they give you an achievement, and without them you can't finish the game to 100%. Otherwise they're useless.
Comment: So you just need to *find* them, but not keep them in your inventory? Do you need to have all 7 at once to get the achievement (i.e keep them until you find them all) or can you get them separately/across multiple playthroughs?
Comment: With the achievements for matching sets of armor i'm pretty sure you need to be wearing them all at once on a single character.  I got the chitin armor one at the moment I equipped one of them pieces, **not** at the moment I picked it up.  So that means that if you are going for those achievements you need to save them, or stash them somewhere (near end of level is my recommendation) and mark the location on the map.  It's good to do this periodically anyway, ie put all your unneeded stuff in a big pile and mark it on the map.

Do I need to keep all treasures?


How do I help a team member be more confident?

Question: I have two team members who come from backgrounds that differ from what they're currently being asked to do: how can we encourage them to step up, develop their skills, and learn the new ways?
Comment: What do you mean by 'lacks confidence'? Lacks knowledge maybe? What do you use SQL for? How heavy and tricky is your usage?
Answer: Practice, practice, practice. The only way to get better is by doing. I find that if I want to learn a new language, the best way is to follow along with programming examples.
Comment: Start that team member out with some simple SQL requirements at work, overseen by another member, or to support some aspects of a larger database project. As they get into it and start familiarizing themselves with SQL and seeing it used in real world projects, they'll start to see their options open up and start thinking of ways to use it for other tasks and projects. Have the experienced SQL programmers steer her away from common beginner pitfalls for an accelerated experience.
Comment: Agreed. A mentor can be a great way to learn as the training usually has real world applicability.
Answer: If you're talking about SQL code in itself, it is a relatively easy language to grasp and be productive with.  I'd say she just needs to get a good book, read it and code SQL, and buckle down and start working with it.
As far as the encouragement goes, the desire to work hard to obtain something like this is intrinsic.  But maybe you can explain how its not too monstrous of a language to learn.  She must have some unjustified fear towards the language which you can alleviate.
Or if she's just plain old not interested in SQL she can 1) just learn it and use it or 2) find another job.  That last statement is depending on whether or not this is a requirement for the position.
Answer: I suppose this depends on what you're doing with the SQL.
Surfer513 said that SQL is relatively easy to grasp and be productive with... but that really only applies to the basic CRUD stuff. Up until recently, I wasn't fully aware of all that SQL had to offer but a colleague of mine showed me some of the SQL he was working with for an advanced course in SQL Server 2008R2 (it was geomapping and some other stuff IIRC) and that can quickly get complicated/difficult.
So, if it's basic CRUD you're talking about then a good book, some practice and pair programming (or code reviews) with confidence building feedback should do the trick.
If you're working with some of the more complicated or esoteric bits, then a course or a certification might be called for. People usually feel confidence after a course, because they can say "I passed the course, I know x". Basically, a tangible badge of learning.
Comment: SQL: It's easy to learn, yet hard to master. You can do pretty freaky and complicated stuff with it. It's powerful!
Answer: Make sure you have a test or development database that can be used as a sandbox.  Oftentimes a fear of databases (or any component of a production system) is increased by the feeling that the least mistake will have catastrophic effects.
In the particular case of SQL databases you can show the engineer how to create test tables (CREATE TABLE foo AS SELECT * FROM bar) that can be INSERTed into, DELETEd from and DROPped without consequence in the sandbox.  Make sure that the sandbox has at least a subset of production data so the effects of things like indexes and full table scans can be experienced directly.  Demonstrate the EXPLAIN statement to remove some of the mystery from what can seem like somewhat arbitrary and magical SQL incantations.
You might also point out that both COBOL and SQL date from the relative dark ages of the computer business with COBOL having the slight seniority but both far predating things like the personal computer and spreadsheets.  Whether this is a comfort or not probably depends on the individual.
Answer: Just ask her some questions (maybe during a meeting) that can be answered by running simple SQL statements on a database, like "Sandra, how many customers do we have in New York right now?". Start it simple, it should encourage her to be able to answer that right away, so make sure it's on her level of knowledge. Make questions more difficult over time. (like what was our sales volume since we implemented the automatic payment system).
When you are sure she can do it, you can ask such questions in customer meetings as well. Customers are soooo impressed if you just hack something in a commandline tool and get the results and it may be a highly encouraging experience to her.


Is there a way to test if someone has said something in chat?

Question: What I want to do is make a command that allows me to say something like "home" in the chat, and have a command block teleport me to my house. Is there a way to test for a word in chat?
Comment: No, but you could use book and quills. I once made a system that detected players who had written commands in books and quills, and when they had, they had something execute at them. It's currently in one of my singleplayer worlds, but I'm not able to access them at the moment. If you give me a few days, I can send you the world, or the commands I used. (By the way, one command I had set up was /home.)
Comment: One way to monitor chat is to have "choose-your-adventure" format, ie made with `/tellraw` commands that have a click event which causes the player to choose what they say, and control functioal reactions by setting `clickEvent` areas to place redstone blocks in a possibly remote system.
Answer: You cannot test for what someone has said in chat. You could however set up your own custom /trigger commands.
You can do this by first creating a "trigger" type scoreboard objective:
/scoreboard objectives add home trigger

Then enable it for whoever you want to be able to use it:
/scoreboard players enable @a home

Any player who has it enabled, even non-OPs, can now use /trigger home set or /trigger home add to manipulate their "home" scoreboard objective.
You can add a /tp @a[score_home_min=1] X Y Z on a clock to have it so anyone who does /trigger home set 1 in chat is teleported home. Follow it up with setting their home score back to 1, so they aren't constantly teleported, and re-enable the objective for them, so they can use it again.
Comment: @tuxedoandex It tests if the player types `/trigger home` into chat. It won't appear in chat for other players as it's a command, but appearing in chat for other players to see does not seem to be a requirement for OP's question. It's more of a workaround than *exactly* what was wanted, but it should still work.
Comment: Sorry if I missed something, but how does this test if the player is saying something in chat?
Comment: THIS CHANGES EVERYTHING! you could make reformatted commands so typing "/trigger spawn" would teleport you to spawn, thus bypassing the needs for plugins! THANK YOU!!!
Answer: Not in vanilla Minecraft, no. There is no way in vanilla Minecraft on a vanilla server to implement any sort of custom chat commands, or detect any sort of chat events.
Answer: In addition to the above answer, if you're using the home functionality, you might also want to repeat the steps above to create a sethome trigger, then use a command to set an armorstand there with a unique name.
See How to enable home / sethome on a Vanilla Minecraft Server
Answer: Yes, it's possible to /testfor if someone is saying something in chat but you need plugins (/testforchat). Then you put in any text that you want the player to say and then you can mess around with it.
Comment: What plugin is this exactly?


Increasing or decreasing BS-formula respect their parameters

Question: The Black-Scholes formula depends of many parameters, is easy to note that it is increasing respect to the parameter $S_t$, $\sigma$ and $r$, it means to fix a all parameters and vary only one. Is possible to say the same for the strike price $K$ or the time $t$, I think BS-formula is decreasing respect to these parameters, it is easy to see for $K$ at time T because the formula gives $(S_T-K)^+$ but not sure. If anyone has an explicit proof of this I really appreciate it. Thank you!.
Answer: In both cases, for European options, it's a matter of determining whether the first derivative of the call price w.r.t. the parameter is always positive or negative. That said, intuition and good financial arguments are always helpful and can often be more enlightening than using the math.
In the case of the strike price, I like your argument -- to make it very slightly more formal, you can say that if Call A had a higher strike than Call B, but also cost more, there would be an arbitrage opportunity. (Again, you can inspect the derivative to see also.) Of course, using the same argument, we can see that the opposite holds for puts.
For theta, I'll link this answer as well as this link giving the formulas for theta. Particularly, we can see by inspection that for non-negative interest rates (and for 0 dividend yield), theta for a call is always negative (in this case, in the formula we are adding two terms that are only ever negative), this is not the case for puts. Put theta can be positive or negative even with positive interest rates, but in practical terms, theta will be negative for most traded options.


How can I reorient the axes of an object?

Question: I spent some time in Unity yesterday trying to fire a sphere from a horizontal cylinder (like a ball from a cannon). I was using Vector3.forward, but the sphere kept coming out the top of the cylinder rather than the front. Someone suggested using Vector3.up instead, and sure enough it worked!
The cylinder is vertical by default. So, it appears that when I rotated the cylinder by 90 degrees to lay it flat, the local axes remained the same. The relative front of the cylinder remained at the same point, so when I fired the sphere it shot out the new "top", not what looked to me like the "front". If I had happened to be facing the other way, I would have had to fire at Vector3.down instead.
How can I reorient/reset the axes of an object so that they match my expectations? (And if I can't, how can I tell by looking which way an object is oriented?)
Answer: Click on the object in the scene, and look at the Rotation values in the Inspector. This will tell you which way the object is oriented in absolute terms.
If the orientation does not match your expected axis (for example, 90 degrees off, or using an unintuitive axis for a given direction), you cannot change the axis of the object itself. Instead, you can use a "parent transform" as follows:
Create an empty GameObject as a parent of your object, and align its transform with your model's expected axis. Now use the parent transform to reference and manipulate the child object.
Answer: Try using transform.up and transform.right instead of Vector3. Vector3 takes the world coordinates and transform.up takes into account the transform's orientation.
Comment: hmmm, I think I misremembered and I actually was using transform.forward (and that didn't work) - I'll have to check my code and comment further... thanks for the tip
Answer: But if your model don't be modeled to get the axis z to front in the modeller program you can't arrange this in unity


Is is possible to have a different sources.list file on the same machine, and each assigned to a different user account?

Question: I want to set up a user account on my laptop to access the network of my office, and in order to do that i need to install applications using my office ubuntu repos, is it possible to create a sources list file to use only by 1 user account, and the rest to use the common sources?
Answer: You can have separated sources lists, but that only means than each repo you add will be defined in a sources.list file which makes more easy to purge a problematic repos. I did that using ubuntu-tweak (there's an option to store each repo in a separated file in the softwar origins tab). But I don't think you can have diferent sources for diferents accounts, since the sources are system-wide and not account specific.
Think about it, that would mean you would have diferent versions of the same program installed in the same system which would be a potential disaster. If an user install libreoffice 3 from the ubuntu repos but another install libreoffice 3.4 from the libreoffice external repos, the 3.4 would "smash" the 3 installation... not to talk about the potential dependency hell you will cause...
The only way I can think for having a diferent account with diferent repos is making a diferent partition in your laptop but that's having two diferents ubuntu installs in the same computer. Then you can use your "normal" ubuntu at home and your "workplace" ubuntu with the office repos. You can make the install so they share the same /home/user so you'll have the same configuration files, the same user, but diferent programs.
Other solution is to install a virtual ubuntu inside your normal ubuntu trough virtualbox, and link that virtual-ubuntu to your office repos. If your laptop is not much old it can handle a virtual os inside the main os without problems for normal office applications like office and such.
Wish it helps, good luck.
Comment: Actually that is a simple and elegant solution, thanks man
Answer: I believe only one user account is able to install software from any apt repository: root. You don't have to login as root, of course. You normally use sudo to direct the root user to perform these actions on your behalf, but it's still being run as root. Since only the root user can install software, it wouldn't make much sense to provide a sources.list per user. But if you want to separate the office repos from the other ones, then you might add the deb-line(s) in a new file and place it in /etc/apt/sources.list.d/.
Your question wasn't easy to understand, though, so perhaps I misunderstood?