How can you prevent your characters from being too predictable?

Question: How can you prevent your characters from being too predictable? I am wondering how to do that, because if your characters have clear motivations and clear personalities, then it should make them rather predictable, so the only way I can make my characters unpredictable is by making them act out of character or making sure there's some kind of plot twist where an hidden agenda is revealed. Am I correct or are there other ways to achieve this?
Answer: Being predictable isn't a bad thing. Arnold Schwarzeneggar's famous catchphrase "I'll be back" was first said by him in "The Terminator". The line, written by director James Camron, was intended to be a "rewatch" bonus... I.E. most people wouldn't pay any attention to it when they watched the film for the first time... but the humor of the line would be apperent on a second viewing. Howerver, Camron found that on a test screening, the audiences were laughing at the line without the pay off... They had understood that the Terminator's character was a master of understatement and over the top violence that by the time the line appears in the film, the audience were laughing. They knew that the seemingly innocuous line was a threat of something big when the character said it, and while they had no idea what stunt he would pull, they knew the poor policeman was not going to anticipate it.
Being predictable in character has it's positives, in that you can set up some great character humor if you can anticipate the character's response to a given situation.
Answer: Think about real people. We're contradictory creatures and although we have traits and behavioural tendencies, we also act against those for various reasons, for example:

We don't like a trait or habit and try to counteract it.
We learnt contradictory things as a child, leading to mixed reactions as adults.
We behave in different ways with different people because we react to their attitudes.
We don't even realise ourselves that we have an internalised belief until we're thrown into a difficult situation and blurt out some ugly words.

If you see characters as just a list of traits and flaws then yes, they will probably become predictable. I suggest spending time on characters' backstories, their upbringing, and what experiences their values come from. This will inform their actions and words in a way that might be less obvious.
Of course, everyone's predictable some of the time, and the more you know someone, the more likely you are to be able to predict what they will do or say. As an author, you should know your characters really well, so to you they're predictable, but remember that your audience doesn't know them, so things that are predictable to you will not necessarily be predictable to your readers.
Answer: Recently I watched https://en.wikipedia.org/wiki/Runaway_Jury.
Fitch (Gene Hackman) is the predictable bad guy. Nicolas (John Cusack) is introduced in a believable way "don't want to be in the jury", asking friends for escape strategies.
Very soon several events shade doubt on his agenda, e.g. when meeting this woman first in a store, later in his home. You know sth. is going on, but have no clue about it. The whole story is logical from the various perspectives … until the very end …
You could say, Nicolas is predictable unpredictable, and so are his actions. Nothing is mentioned about the second story running in parallel, "colliding" at the very end, making things evident in hindsight.
There may be more films to learn from. Many follow a similar scheme, but not all.
Take Monk as an anti-example. This character is perfectly predictable, which is part of enjoying, introducing a new facet of his behavior every now and then, while the relevant story follows a similar collision path, only revealed in the last scenes.
Or take Columbo. The crime, the criminal, the victim, the motives are completely revealed at the beginning. So the criminal is perfectly known and somewhat predictable, inspector Columbo is absolutely predictable. The sensation arises from the kind of chess game good vs. evil, waiting for relevant contradictions, hence evidence. It's so well designed as a story, though you know almost everything from the start, that I enjoy it again and again.
So, draw your conclusions about working with the predictable unpredictable.


Correlation of the strength of the Balmer lines with the age of a galaxy

Question: I don't understand why a strong absorption line H$\delta$ indicates a young star population.
First of all, a strong H$\delta$ line just means that I have more A-type stars, doesn't it? Where is the connection to the age of a galaxy?
Answer: A-stars have a main sequence lifetime of < a billion years and are much more numerous in a burst of star formation than the higher mass, and much more luminous O/B stars. The Balmer lines, particularly H$\delta$ are particularly prominent in A-stars compared with both hotter and cooler stars.
Lots of H$\delta$ tells you that the light is being dominated by main-sequence stars that are aged between about 200 Myr (after which the more luminous OB stars have died) and 1 Gyr, after which the A-stars will have died and H$\delta$ would be considerably weaker in cooler, longer-lived stars.
This simple argument applies to a single burst of star formation - a simple, single stellar population. Prolonged, or multiple epochs, of star formation will confuse the issue and require more detailed modelling.


What happens if someone travels by car and then decides to sell/dispose of the car there?

Question: What happens if someone drives a car to a country (international, Schengen  excluded) and suddenly decides to sell/dispose of (e.g. broken) the car there and take a flight back to home? Does he/she (driver, passengers) have to pay a fine at the airport?
Comment: This depends entirely on the country and its customs laws, as some may care that the car wasn't exported, some may have systems to track that while others may have no idea, and some may have appropriate exceptions if the car is below a certain value. Do you have a specific country in mind? Note that simply leaving (abandoning) a car is generally illegal in and of itself.
Comment: Depends one which country, whether they know they came in by car, how the leave your car behind is organized and so on.
Comment: Also depends on the country coming from, e.g., if entire route is Schengen, nothing is checked along the way.  However, if the car is sold or abandoned, it _can_ be traced to the previous purchaser if the local authorities wish to do so.
Comment: As i said Internationl so schengen is kind of excluded
Comment: Schengen is still international. But I take that you understand it has fewer registered travel moves. Other EU countries have no registration of cars coming in either.
Answer: I think it will greatly depend on the country.  Each country sets the rules independently.
Here in Canada, you could not register a vehicle in this country unless it were legally imported.  The temporary importation you would have been permitted when entering Canada by road from the US, or by sea from other countries, would not permit you to sell the vehicle here.  Now, of course, if you had a serious accident or mechanical failure, an exception would likely be made.  Technically you would have to contact Canada Border Services Agency and declare the vehicle's permanent importation, but to my knowledge there is no process where they are notified if you were simply selling your vehicle to a junkyard to scrap.
Note that foreign vehicles may have limited scrap value if that particular make and model is not sold in the country where you scrap your vehicle.  It may only be worth a few dollars for the metal content.
If you simply abandoned the vehicle, you could be identified via its registration and/or VIN (serial number) so this isn't wise.  It would be best to sell it to a junkyard or automobile recycler.
If the vehicle is roadworthy and you simply wish to not drive it anymore, you may not have a choice - legally you need to re-export it.


Find wi-fi router in LAN acting as a repeater

Question: I have a router which acts as LAN repeater, but I don't know its IP. If I tracert my firewall (gateway), it won't show my wi-fi router.
Question: How can I find it?
I tried to nmap all my network looking for an open HTTP port, but nothing.
I also tried to unplug the cable coming from my firewall, but It doesn't have DHCP set.
Comment: Does the repeater have a different/distinct SSID? Doing a wireless site survey might be a start - then you can work out its mac address and work from there. I've also had situations where a system *didn't* have an IP address I could find, and was entirely non responsive to my attempts to configure it, yet worked as a AP and 'switch'
Comment: Do you need to physically find the device? Or do you know where it is physically, and you just want to find its IP address?
Answer: When I have a device with a static IP address that I've forgotten, I usually plug it directly into my laptop via Ethernet (with a crossover cable if your laptop doesn't do auto-crossover/auto-MDI-X), then run tcpdump or Wireshark or another packet sniffer, and then power-cycle the device.
On boot, most devices will use ARP to make sure their static IP address is not in use by someone else, before using it themselves. So you can look for those ARPs to see what IP address the device is trying to use. Also, devices that do peer-to-peer name resolution and service discovery protocols will often make a few announcements or queries/probes at boot, so look for those packets too.
Make sure to use a filter in your sniffer to filter out any traffic your own laptop is sending. You just want to see what the device is sending.
Answer: If your main router is also the DHCP server an not the repeater,
the simplest solution is to find the repeater's IP address in router's DHCP
clients list.
This may look like :
Answer: Kinda sadly, the best tool I have ever found for network discovery is the network mapping tool from Windows 7 (AKA LLTD). Nothing else I've used comes close, and it will even show you switches and other devices without an IP address. Here's an example where it was the only tool that could even detect a specific device on a network.
There's a plugin for zenmap that does the protocol, but it seems nowhere as complete as the Windows 7 version of it. There's also a Linux scanner that does it here, but I've not had much luck with it either.
You haven't really mentioned what OS you're on. You shouldn't be just looking for a open http port. Many routers use https or non standard ports. Sometimes people just turn it off. That said - nmap (or zenmap) should be giving you the information you need.
If all else fails, consider resetting it, and setting it up again. It would likely be quicker.


iOS TabView with Unity3D integration

Question: Has anyone here been able to integrate a TabView based application with Unity3d? I have been working on a solution, but I'm beginning to believe that it may not be possible to do. The concept basically is to have the Unity3d OpenGLES view paused upon the start of the app, and have one of the tabs contain a button that un-pauses the OpenGLES view, and hides the TabView controller. Am I crazy for wanting to do this? Any help or suggestions would be greatly appreciated
Answer: there is a plugin called NativeToolkit  by Prime31, its free... I havent tried it, but the description says that it does exactly what you want, I tried the gamecenter plugin they offer and its amazing how easy it is to integrate, it seriously works "out of the box"
oh yeah and the NativeToolkit plugin is free too :) give it a try

iOS TabView with Unity3D integration


Is it a problem to frequently change a Tor relay's fingerprint

Question: If each time Tor relay is started with a different key pair, would it be a problem for the Tor network to recognize it?
Answer: The relay would be considered 'new' each time. It would never gain the 'stable' flag or gain much consensus weight.
This would neither hurt nor help the network.
Comment: What if the same machine switches between only two different public keys? That is, does tor consider the mapping of public keys and IP addresses to tell whether a relay is stable, or public key is the only factor that matters?
Comment: Please add the comment as another question. This helps other to find the question and to answer it in a reasonable way.


Remove artifacts from OSM roads data in QGIS

Question: I downloaded OSM data for Amsterdam from the bbike website. Opening the roads layer in QGIS I get these strange artifacts where road sections cross the whole map in a straight line. What would be the best way to correct/remove them? Has anyone else had this effect with OSM data?
Answer: Same here, it seems to be an internal error in the postprocessing of the OSM data at bbike.
You can take the osm.pbf file from the same website, which works for me, or take the shapefiles from Geofabrik and cut out the area you need.
Answer: I would suggest first checking to see if the artifact lines share any common attribute that the others do not. If that is the case then select all features with that attribute and remove them.
Otherwise it seems like the artifact lines are very long so you could try selecting all lines with a length over a certain threshold and see if that snags the artifacts and not the genuine lines?
Also you might need to check if they are just single vertices which are out of place. If so the most accurate solution beyond finding better data would be to try and manually delete the incorrect vertices using the Vertex/Node Tool.


Does the $H_2$ in cosmic clouds virtually not radiate?

Question: I am reading the lecture notes of a friend. He has written about the cold (3-20 K) molecular $H_2$ cosmic gas, that "practically doesn't radiate, due to symmetry". Can someone confirm that $H_2$ has this feature of radiating much less electromagnetic radiation than other molecules? And how can this be explained with the symmetry of the molecule? Excuse me, for making you interpret vague statements. Nevertheless, I am very curious
Comment: Possibly the lack of rotational transitions? Homonuclear diatomics do not undergo purely rotational transitions since their symmetry means they have no dipole moment.
Comment: @JohnRennie Thanks, this is helpful! Can you explain a bit more why dipole moments are required for rotational transitions?
Answer: Yes, it is correct that cold $H_2$ radiates much less electromagnetic radiation than other molecules (for example, carbon monoxide).
Here's one way to think about this intuitively.  On macroscopic scales, electromagnetic radiation is produced when charged objects accelerate.  The atoms in a hydrogen molecule consist of charged particles (protons and electrons).  These particles are certainly capable of accelerating.  However, since momentum is conserved and the two hydrogen atoms are identical, if one of the atoms accelerates, the other atom must accelerate by exactly the same amount in the opposite direction.  Therefore, the radiation from the two atoms cancels out.  (This assumes that the molecule does not interact with other molecules, which is very reasonable in the interstellar medium.)
At molecular scale, the relative acceleration of the two atoms in a diatomic molecule becomes quantized as rotational and vibrational transitions.  But the same intuition applies: if the molecule rotates or vibrates, conservation of momentum implies that there is no net radiation.
Of course, the protons and electrons in the two atoms can still accelerate relative to each other.  Since protons and electrons have very different mass-to-charge ratios, this does produce radiation.  However, the proton-electron interaction is much stronger than the atom-atom interaction.  Using quantum mechanics, that means that the available energy levels (the electronic levels) are much more widely separated than the rotational and vibrational levels.  At the very low temperatures of the interstellar medium,  there simply isn't enough energy available to jump between different electronic levels at any significant rate.  As such, interstellar hydrogen can't produce much radiation through this process either.
Comment: Thanks for the long explanation! Does your first paragraph mean that the 2 atoms in H2 radiate, but the radiation interferes destructively? Can you also comment on John Rennie's comment - that rotational transitions don't occur in symmetric molecules and why?
Comment: @NeStack Yes, I think that "the atoms radiate, but the radiation interferes destructively" is a reasonable way to think about what is happening.  However, I would caution against taking the classical description overly literally here – it can easily give you the wrong intuition.
Comment: @NeStack I agree with John that homonuclear diatomics do not undergo purely rotational transitions.  To expand a little, if the atoms were different, the molecule would have an electric dipole moment (because one atom would attract the electrons more strongly).  Therefore, rotation would result in a net acceleration of charge and thus EM radiation.


How to reproduce this shot of a person with reflections in front of them?

Question: Renuka Puri: Portrait of Prime Minister Narendra Modi and reflection of crowd in the glass after the parliamentary party meeting
How can I reproduce this shot, especially the reflections in front of the person?
Answer: This shouldn't be too hard. The photo was shoot through a pane of glass. The glass is at a slight angle, reflecting the crowd.
Here is an example of how to do this:
<code>                  000000  <-  Crowd
       Glass
          \
Subject    \             <- [} 0 You pointing your camera at the subject
            \                 \|
</code>
This way the crowd is shown on the glass along with the subject. You'll have to experiment with angle and exposure to more accurately replicate this.
As for camera, any will do. Make sure that you aren't using a polarized filter as that could reduce the reflection.  Shoot at a longer focal length (100mm or more) to make the distant crowd look larger in the reflection.  Knowing this, you can also experiment with different focal lengths to see what you like the best.
Comment: Do I need any special camera or any DSLR will work?
Comment: Any dslr works. This photo specifically was shot on a longer lens, maybe 100-200mm. This compresses the background, making the crowd look closer to the subject. I'll update my post with that information.
Comment: Polarizing filters can be used to enhance, as well as reduce, reflections.  You should use one in this type of shot to adjust the reflection to the desired amount.


How to keep my (deep frying) oil usable as long as possible?

Question: I have a new deep fryer. I am pleased with its results so far. I am not a 'heavy user' though - say once every 2-3 weeks. I want to re-use the oil a couple of times. The deep fryer is covered but not airtight, however.
The new deep fryer has a cold zone, which means the oil won't become dirty due to particles over-frying. I don't overheat the oil either. So, in principle, I'm frying correctly, I think.
So, how long can my oil safely sit in the deep fryer, if I ensure it's thouroughly heated next time I fry? Should I be allowing the oil to cool and store the fat in (sealed) containers instead, if there's going to be this long a gap between uses?
Edit: yes, I've seen this question and answers: Frying Oil Reuse
Comment: My family has always reused the oil until it either looks wrong (too viscous or a funny colour) or smells wrong (burnt, of food, or rancid). We keep the oil in the fryer and take it out to filer it after it's cool. I'm not sure if this is wrong but it doesn't appear to have done any damage so far. I'd say we use the fryer once a month and change the oil a couple of times a year.
Answer: First thing, a cold zone doesn't prevent particulate build up, it just cuts down on the amount that will remain suspended in the oil. You should still filter if you want to keep your oil as long as possible.  You can detect bad oil (meaning rancid) by a few ways, like smoke point or smell.
You should store your oil someplace dark and cool, which could be the inside of your fryer as long as you filter and clean the sides before you stick the oil back in.  Another thing you can do to extend the life of your oil is switch to tallow (beef fat) or rended pigs fat (lard) as saturated fats do last a lot longer than the poly-unsaturated.
Once again, you should lose the oil when the smoke point drops, or if it is to dark, or if it develops any foul odor.  And as I said before, once you use the oil once, you should NOT use it past six months under any circumstances, if you do, you are taking your gastro-intestinal tract into your own hands.
Comment: Could you share references for the "6 months old oil gastro risk" fact that you stated please?
Answer: I would not reuse that oil. The frying-oil reuse that occurs in fast food chains is reuse for the same day or over just a few days. They also store it properly and not just sitting exposed in the fryer.
justkt is correct that more saturated fats are less sensitive to breakdown, this is why bacon grease can be kept for a rather long time.
Three factors play a significant role in oil degradation:
Oxidation
Any contact with air causes oxidation in oil. High temperatures, metal alloys, surface exposure, and even UV light act as catalysts to this reaction.
Hydrolysis
When water interacts with oil it causes it to taste tainted or acidic. This is exacerbated by high temperatures, heating/cooling cycles, and oxidation products.
Polymerizaton

When frying oil deteriorates, the resulting products form both volatile (or reactive) and non-volatile compounds. Non-volatile compounds remain within the frying oil, and can produce polymerization at frying oil temperatures above 200°C (390 F) or in isolated hot spots within the frying system. These molecules bond together to form large, different-sized clusters that accumulate on the oil's surface. Since they don't dissolve, they cause foaming; trapping air under the oil, and increase the possibility of hydrolysis.

Given all these, the best environment for any oil is an cold, dark, airtight place. Cold temperatures may cause clouding, but this is not a cause for worry.
Source:
http://www.heatandcontrol.com/technical%20articles/Maximizing%20Cooking%20Oil%20Life.pdf
Comment: Actually, almost all oil is left in the fryers exposed to air and whatever else comes along in fast food restuarants.  You'd be lucky if they even throw a pan over the top. Also, ruse is a matter of days to weeks rather than hours to days, but that is because the industry has filters that run at least twice daily and filter powder that removes the harmfull stuff out.
Comment: naw, why cover something that absolutly nothing can live in once its at temp? but like I said, there is an entire sub industry devoted to extending the life of your oil in the fast food world. I wish I could post some of the oil management training materials, they are pretty brilliant.
Comment: I know, but for fast food, oil quality is destroyed through use long before it can degrade any other way.  Its a special case, unlike anything else that normal restuarants have to do to mantain quality.
Comment: @sarge: Really? I don't have any fast food experience. I assumed they at least covered it.
Comment: @sarge: has nothing to do with what can live there, but the quality of the oil
Answer: One important note is to use a more saturated oil to avoid breakdowns that form the toxic compound HNE.  See Science Daily for a summary of the research.  One of the authors of the quoted research has written many more papers on the issue. If you use a highly unsaturated oil you can only use it for half an hour at frying temperature before HNE begins to form.
Comment: This seems to run counter to common practise (as also mentioned in the other linked question) in both fast-food joints / restaurants with fries. Is it common to be able to buy the 'wrong' type of oil (in a Western European country)?
Comment: @Tobiasopdenbrouw - are you sure that they use vegetable or another highly unsaturated oil for at least 30 minutes at a frying temperature?  There appears to be a growing body of research on HNE and oil out there - http://www.springerlink.com/content/l016112242257293/.
Comment: no, I'm not sure about this.
Answer: FROM
http://www.fsis.usda.gov/wps/wcm/connect/65f762d0-e4d0-4278-b5cb-2836854a3eda/Deep_Fat_Frying.pdf?MOD=AJPERES
If you are planning to reuse the oil, strain it through
a cheese cloth or sieve. Store the used oil in a sealed
and light-proof container for up to 3 months. For best
quality, refrigerate used frying oil that you want to use
again.
If the oil is clouded or if the oil starts to foam or has
a foul odor, taste, or smell, discard it.
Answer: I keep my old plastic coffee cans for storing the oil in after use. They are large enough and seal tight. I also store it in the refrigerator. It does get a little cloudy but once heated it clears up. Probably use 4 or 5 times in 3 to 4 months unless I fry fish and then it gets thrown away. It tends to get a slight odor after that even if it isn't dark. I always strain it before putting back into the fryer.
Comment: if you fry a potato in the oil after you cook fish it will absorb the "Fishy" taste>
Answer: I use my oil about ten times and never have I taken it out of the deep fryer. It usually sit between uses about 2-3 weeks every time and it is always ok.
Answer: First let me say that I RARELY deep-fry anything.  When I do, I use a large deep saucepan to fry in.  When finished, I let it cool down then put the lid on the pan and cool overnight.  I then pour through a fine mesh sieve into a large mason jar, seal and put in upper cabinet.  It is in the dark most of the time, and away from heat, not over the stove or oven, and this seems to work out just fine for me.  I usually discard after about 5 or 6 uses, depending on what I'm frying.
Answer: I would think that fresh oil would be best used, as even though the oil may be strained and cooled in fridge, it will still contain some of the cooked substance, and recooking stuff over and over is not healthy.


what are the best sources to learn about statistics?

Question: am interested in quant analytics. hope statistics is heart for quant analysis.
so, what are the best sources to learn core statistics (in depth) and what is the best approach to learn statistics?
Answer:
Sheldon Ross - A first course in probability. Probability is the foundation of statistics so this is a good place to start

Cassela & Berger - Statistical Inference. This will give you a solid understanding of the ideas behind confidence/prediction intervals, hypothesis testing, all the way up to to linear regression.

Hogg -Intro to Mathematical Statistics. This is heavy on analytics. Good if you're comfortable with higher level math.

A good book on linear algebra so you can get a better understanding of how things are working under the hood. It's not strictly necessary but definitely helpful.

Those 4 will get you started but they're just the beginning.


Evaluate $\displaystyle\lim_{j\to0}\lim_{k\to\infty}\frac{k^j}{j!\,e^k}$

Question: I found this problem in my deceased grandpa's note today when I was visiting my grandma's home.
\begin{equation}
\lim_{j\to0}\lim_{k\to\infty}\frac{k^j}{j!\,e^k}
\end{equation}
I asked my brother and he said the answer is $\cfrac{1}{2}$, but as usual, he didn't give me any explanation why the answer is $\cfrac{1}{2}$. I only get the indeterminate form $\infty^0$ in the numerator part if I substitute $j=0$ and $k=\infty$. I have no idea how to answer this problem. Could anyone here help me to answer it? I really appreciate for your help. Muchas gracias!
Comment: Who did give my question **a bounty**?
Comment: I did .$\phantom$
Answer: The sum was probably transcribed wrong somewhere along the way,because it doesn't make much sense as written (the limit as $j \rightarrow 0$
of something involving $j!$ ?).  But since the answer is supposed to be $1/2$,
I'm guessing that the intended formula was something like
$$
\lim_{k \rightarrow \infty} \sum_{j=0}^k \frac{k^j} {j! e^k},
$$
which I'm sure I've seen before (possibly on this forum or on mathoverflow)
but can't easily locate a reference.  If we had replaced
the $\sum_{j=0}^k$ by $\sum_{j=0}^\infty$ then the sum would equal $1$
for all $k$, because on writing
$$
\sum_{j=0}^\infty \frac{k^j} {j! e^k}
= \frac1{e^k} \sum_{j=0}^\infty \frac{k^j}{j!}
$$
we recognize the sum as the power series for $e^k$.
So the problem is asking in effect to prove that as $k\rightarrow\infty$
the $\sum_{j=0}^k$ part of the sum is asymptotically half of the
entire $\sum_{j=0}^\infty$ sum.  To see that this is at least plausible,
observe that the $j=k$ term
is the largest, but still accounts for only $O(1/\sqrt k)$ of the total,
and the $j=k+1, \, k+2, \, k+3, \, \ldots$ terms are approximately equal to
the $j=k-1, \, k-2, \, k-3, \, \ldots$ terms respectively.  There are
various ways to finish the proof, and your brother can probably point you
towards one of them :-)
Comment: I forgot to say thanks. Thank you Sir for helping me out and responding my message. (*^-^*)
Comment: Hmm, this is supposed to be the complete problem. It seems make sense. I've learnt Taylor series by myself, the answer should be 1. OK, I'll accept your answer if I can prove the *intended* formula that you proposed equals half.
Comment: I understand now Prof! Although I had lots of trouble to prove that it equals half. Thank you so much for your help. ≧◠◡◠≦✌
Answer: Unfortunately, your brother is incorrect. Note that
$$\lim_{k\to \infty} \dfrac{k^j}{j! e^k} = 0$$
Hence,
$$\lim_{j \to 0}\lim_{k\to \infty} \dfrac{k^j}{j! e^k} = \lim_{j\to0}0 = 0$$
Even by mistake, if he had interchanged the order of the limiting process, we still get the limit as $0$, since
$$\lim_{j\to 0} \dfrac{k^j}{j! e^k} = \dfrac1{e^k}$$
and therefore
$$\lim_{k\to \infty} \lim_{j \to 0}\dfrac{k^j}{j! e^k} = \lim_{k\to \infty} \dfrac1{e^k} = 0$$
Comment: Luckily, you've edited your answer. I almost lost my temper and voted down your answer when you said "my deceased grandpa is incorrect". Just kidding, I won't do such a bad thing. Definitely, I appreciate your answer and also every answer. Hmm, your answer seem correct that was also my first thought, but why did my brother say the answer is $\cfrac{1}{2}$? Did he trick me again??


What part of this picture demonstrates the wavelike properties of light and what parts demonstrate the particle-like properties?

Question:
Back in march some scientists took the first picture of light as both a wave and particle. I was wondering what parts of the image actually demonstrated these properties. I have some ideas, but the more I think about it the more I get confused.
Comment: Me too.  I read the blurb you linked.  The explanation there doesn't compel me to think of photons as particles.  It says, as far as I can tell, that the energy exchange by the electrons and the EM field is quantized.  You don't need to model the photon as a particle for that to happen.  It's possible that the blurb doesn't reflect the experimenter's interpretation of the results.
Comment: The double slit experiment with a single photon at a time displays the dual nature of photons.  I agree with garyp that the explanation given is not unique.
Comment: How does a double slit experiment display that? I'm in AP Physics 2, so I'm no expert, but we did that experiment to show light's wavelike behavior due to the interference generating the pattern.
Answer: I post this in an answer because it's too long for a comment.
Lesson no.1 in handling info sources: When something sounds fishy in a (science) news article, always check the original sources.
In this case, scroll all the way to the bottom of the article and check the title of the original Nature article under "More info": Simultaneous observation of the quantization and the interference pattern of a plasmonic near-field. This already tells us that the authors referred to "quantization and interference", not to "particle and wave". If we now check their Abstract, we find that they "demonstrate the ability of ultrafast transmission electron microscopy to simultaneously image both the spatial interference and the quantization of such confined plasmonic fields." Again, nowhere in the Abstract do they mention "particle and wave", but they do insist on "quantization and interference", and for very good reason: This is what is observed, regardless of any particular interpretation. Now, if anyone wants to connect the dots between "quantization" and "particle", it's frankly their separate problem. Personally, I wouldn't go for it, but the author of the news article probably thought it sounds close enough.
Comment: Wired and discovery have articles making the jump to particle & wave as well. Not sure if that means anything, but it's not just the Author of this article.
Comment: In my experience science news articles kinda propagate on a weekly basis, sometimes monthly, from an original source that is usually Phys.org, Physics (APS), SciAm, Nature, etc, to secondary sources. They generally rely on one another for the basic facts and terminology, so if someone sets the tone, others follow.


Blocking websites on OS X

Question: I would like to block some websites on the guest account, so my cousin cannot browse things that are not safe for my computer.
Comment: What is your definition of not safe?
Comment: You want to block content or certain URLs?
Comment: There are many many parent control apps out there.
Answer: You can do this using Parental Controls on the Guest account. See Apple's KB article regarding this for the procedure:

OS X Mountain Lion: Filter inappropriate Internet content

Manage a user with parental controls

Choose Apple menu > System Preferences, and then click Parental Controls.
Click the lock if it's not unlocked, and enter an administrator name and password.
Select a user in the list of users, and then click Web.
In the Website Restrictions section, select the Internet restrictions you want for Safari.

To allow Safari to access Internet content without filtering, select "Allow unrestricted access to websites."
To filter inappropriate Internet content or websites, select "Try to limit access to adult websites automatically."
To allow or restrict specific sites, click Customize.
To limit access to only specific websites, select "Allow access to only these websites."
To add a website to the list, click Add (+) below the list, choose Add Bookmark from the pop-up menu, enter a bookmark name and webpage address, and then click OK.
To add a bookmark folder, click Add (+) below the list, choose Add Folder, and then type a name for the folder.
To remove a bookmark or bookmark folder from the list, select it and click Delete (-) below the list.

But to fully protect the computer from potential harm from Internet regardless of account used one has to block any downloads and installations without explicit approval. (I do that to protect my self from my self :)
Each browser has they own set of tools that can be used to protect user and computer. Loots of good add-on's in Firefox.
As an example for Firefox you would use a add-on ..Block downloads,
lock down bookmarks/addons/downloads with a password.
Comment: The link you provided to the Firefox example contains a broken link to OS X Parental Controls and a search for parental controls extensions. Could you expand your recommendation for Firefox? Which extension would you recommend? Furthermore, could you expand on why you would need to block downloads and how leaving downloads available would affect things? Why would bookmarks/addons need to be password protected too?
Comment: @grgarside, thanks, link fixed, why blocking downloads is kind off self explanatory, since the OP is concerned about damage to the computer.
Answer: When you use the Guest Account feature, it is isolated from the rest of the system. The guest user has no administrative rights and anything that is saved by the user is deleted after logging out. You can fine tune what the guest user has access to (this is a good article) but AFAIK, and in regard to whether or not your cousin can download something that would be harmful to your computer, the Guest Account is completely safe to use.
According to Apple:

Important: Files created by a guest user are deleted when the user logs out. A temporary home folder is created for the guest user's files, but this folder and its contents are deleted when the user logs out.

and with even more restriction:

When FileVault is turned on, guest users can only log in and use Safari. Guests can't access your FileVault-encrypted disk or create files. Instead, they log in and use Safari from your computer's built-in recovery disk.

Unless your cousin works for the NSA (I say this tongue-in-cheek), I don't think you have anything to worry about if he is using the Guest Account feature.

Blocking websites on OS X


Is it safe to feed 5v dc 1amp to an Arduino uno R3 board?

Question: Is it safe to feed 5v dc 1amp to an Arduino uno board?
Comment: Yes, it is safe.
Answer: Yes as long as the polarity is correct, the board will only take the current it requires
Answer: The 1 Ampère you're mentioning is likely the maximum rating of the power supply, i.e. it cannot sustain higher currents for a long time. However, if you connect your Arduino board (or any other device) to your power supply, the actually flowing current will depend on the voltage U and the resistance R of the device as I = U/R. You can think of this as the Arduino drawing as much power as it needs.
In other words: you must not exceed the maximum voltage, but you don't have to (and cannot in a simple way) adjust the current flowing into the Arduino.
Answer: That's a common newbie question: "What will happen when I use a 1 A power supply for a device which only needs 0.1 A?"
The device will only draw the current it needs. It's the same as on your electricity grid. The nuclear power plant can supply a gigawatt, yet the bulb will only draw the 60 W it needs.
But do you want to apply that 5 V to the power connector? Then the 5 V is too low, you'll need at least something like 6.5 V, otherwise the onboard voltage regulator won't have enough headroom to output 5 V. If you're using the USB connector for a regulated(!) 5 V, then the onboard regulator will be bypassed. Never place an unregulated 5 V on the USB connector, though.


What is this bottom bracket

Question: We were doing a volunteer bike repair clinic and came upon this bottom bracket that I've never seen before. It was on a trials bike and the crankset was destroyed but we couldn't find any way to service the bottom bracket and didn't have any matching cranks to replace it with. The bottom bracket was quite large and beefy and like like it would fit a one piece Ashtabula bottom bracket. Didn't end up fixing the cranks as we had no idea how to deal with this.
Comment: The splining makes it look like a [BMX 3 piece](https://www.parktool.com/blog/repair-help/bmx-three-piece-crank-service#article-section-2) crank; if the size is ashtabula, is there an ashtabula to 3 piece adapter in place?
Comment: @Batman It is some form of three piece crank. But this is as much as we could disassemble it. There wasn't anything we could find to remove after this point. Just a flat bearing cartridge and the spindle you see. Everything seemed oversized.
Comment: It's possible that the bearings are compression fit.  But I can barely make out notches on the outer ring about 1/3 of the way around.  Did you try to unscrew the ring?
Comment: Ran my finger around the outside and couldn't see anything to grip by. The notches you see might be damage. The spindle and crank seems to match the BMX three piece Batman linked to, bit the bearing appeared to be pressed in and non removable.
Comment: @nathanknutson  That answer looked decent - what was wrong with it ?
Answer: Looks like this is what's called a "mid bottom bracket". They seem to be common on BMX bikes. They use bearings that press into the frame. I found a video that shows how to remove and install a new one. It seems like the spindle should slide right out from the video but on the bike I was working on it didn't seem like that would have been the case, but I didn't really try to slide it out.

What is this bottom bracket


Outlets for 2 sheds

Question: I want to run a couple of lines from my main box, 1 for 50 amp for my RV and then I want to have 9 shop lights installed (4 to run on one switch and the other 5 on a second switch) and 5 110 outlets between 2 sheds. Should I run a sub panel to the sheds and run everything from it, or just go with 1 big breaker in the main box and split the wires down as I need?? Going to have help with this, but trying to price everything out ahead of time and just not sure which way is best.
Comment: Can't just split wires. Running lots of circuits will likely cost more than a subpanel. Also grounding issues. How far are the sheds from the main panel?
Comment: Depends on your locality.  Generally a sub board per building is a legal requirement, and for me a licenced electrician must do the board work and connections.  Homeowner can do donkey work to reduce labour costs, but ultimately your local code requirements are the authorative call.
Comment: I want to have 2 separate runs,  1 for my boat shed which will only have 4 outlets, 4 overhead shop lights, and 1 light switch. Most I will run in there will be a small air compressor, table saw, or small tools but not all the same time of course. That shed is about 115' from main panel. Other shed will have 5 overhead shop lights, and only 1 outlet but will also have a 50 amp outlet for my rv and thatch shed is about 130' from main panel
Comment: Are the sheds located near each other, or way off in different directions?
Comment: They are about 2' apart from each other
Comment: Is the RV receptacle going to be located on one of the sheds, or on a separate pedestal?
Comment: Separate pedestal
Answer: Going with a sub is really the only option you need over current protection for the lighting and GFCI's for the outlets then your RV. You don't mention what size loads will be in the sheds . NEC 551.72 can be used to calculate the load for the RV not less than 12000va or 50 amps, so you will probably will want at least a 75 amp feeder, I would get a 100 amp panel so there is plenty of room for expansion. Go with the largest feeder (wire size) you can afford, I have never been told to down size panels but have come back on quite a few jobs and upsized feeders and panels with 1 job I returned a 3rd time and the owner said he wished he had listened the first time because now he paid 3x for what I recommended the first time. Go big and save in the long run. You did not say what the distance to the shop is from your panel, this will be important so we can verify the voltage drop.
Comment: Ed it is about 150', give or take a few, to the furthest point. The sheds are like 2' apart from each other. Only thing in 1 shed will be small tools, ex. table saw, small air compressor, skill saw, drill, but they will NEVER be going all together at all. Other shed is just the RV and nothing else
Comment: Here are some numbers 150' at 80 amps would take #3 copper or #1 aluminum the breaker in the main would be 80a.  A 70 amp in the main would use #4 copper, or #2 aluminum. I always recommend to go big. You will probably not be working in the shop when the RV is fully utilized so that can be part of your sizing choice. Hope this helps the reason for the larger wire than the tables show is to keep the voltage drop below 3% this is not a hard requirement by code but many AHJ's require it to be met. I would install a sub with a main since it is a long way back to the house a 100 amp panel will work
Answer: Yeah, that's not salesmanship when we (pretty much everyone here) says "Go Big" on service panels.  The critical factor is spaces -- lots of people come here and say "my panel is full, I'm out of spaces, what can I do?" Never seen a question like "Help, I have all these extra spaces in my panel".
The trick is the subpanel itself has an amp rating, and its master breaker (if equipped) has an amp rating, and those are allowed to be larger than your feed.  So for instance, running a 75A feeder to a 200A rated subpanel with a 150A master breaker, that is fine.  The master breaker in a subpanel is only thereto be a shutoff switch, and its value doesn't matter.  The shutoff switch is required because this is an outbuilding.  Using a panel with a master breaker is the cheapest way to do that.
Answer: Fat conduit is your friend here
First off, I would be running this project in conduit, and Schedule 80 PVC to be precise, provided burial depth is not an issue.  Why? It is far cheaper to pull fatter wires through conduit than it is to dig up and replace a direct buried cable, and it also provides a bit of protection against oopsies when digging.  You also need a somewhat shallower trench with conduit (18" to top of conduit for Schedule 80, which translates into a 21-22" trench depth) than you do with a cable (24" to top of cable).
As to sizing, I would use 2" Schedule 80 here, which provides plenty of space for pulling larger conductors to the sheds and RV pedestal in the future.  As to running it, I would run conduits from the house and both sheds to the RV pedestal, as that's probably the most obvious place logically speaking to make the feeder splices/taps.
Wire sizing and making your connections
Given that you are using conduit, this gives us the flexibility to size our wires for today's needs without precluding tomorrow's upgrades.  As a result, I'd use 3 6AWG THHNs (hot/hot/neutral) with a 10AWG bare copper ground in the conduits, protected by a 70A breaker (using the NEC 240.4(B) "round up" rule).  At the pedestal, we use a trio of insulated mechanical tap connectors (Polaris™ or equivalent) to connect the incoming feeder wires from the house to the feeder wires to the sheds and to the tap wires going up to the pedestal's lugs.
As to the panels and pedestal
You will need a main breaker subpanel at each shed in order to provide a disconnecting means for power to the shed.  Using a subpanel here instead of a lesser solution also provides more upgradeability compared to the alternatives, provided you size the subpanel properly, which is where most folks fall short, as they buy the cheapest panel that will work.
Instead, what you want to do is provision plenty of panel spaces now for expansion, as they are far cheaper to install now than they are to add later.  This leads us to select a 100 or 125A, 24 or 30 space, main breaker panel, preferably with factory fitted ground bars -- if your panel comes without ground bars, you will have to add a set yourself in the field.
As to the pedestal, the configuration I would look at is a dual-receptacle, 50A/20A configuration in an unmetered, earth burial style -- this provides both a 50A/240V receptacle that will provide sufficient power for just about any RV you can find, and a 20A/120V duplex GFCI as a general utility receptacle at the RV location.  (If you wish, you can go with a 50A/30A/20A configuration that also provides a TT-30 30A/120V receptacle, but that is strictly optional.)
Other notes
As of the 2017 NEC, 110.14(D) now requires that all lugs be tightened to the manufacturer's specified torque using an (inch-pound, by the way) torque wrench or torque screwdriver.  Even if your jurisdiction does not enforce this requirement, I would do it anyway, lest your electrical system do what Greg Biffle's infamous lugnuts did!

Outlets for 2 sheds


What Software Do You Use To Create Sitemaps / Site Structure For Large Sites?

Question: Just wondering what software you use to create a visual sitemap / site structure representation before you start big sites?
I am looking to map out a large site, but cannot find any good software to help me map the site visually (And in pages/categories)..
Answer: I strongly suggest taking a look at this tool:  http://www.balsamiq.com/products/mockups
The Balsamiq tool is the best for doing mockups (i assume this is what you are referring too when talking about sitemaps before you start...).  With this software you can quickly generate a working wireframe of what ever you are creating.  So much functionality that you can actually share it with your client to get some good sign offs prior to typing the first bit of code.
Very powerful!
And the other one...just shown at the last MIX09 is SketchFlow.  Couldn't remember it to save my life.  This is a WAY COOL tool for site maps and UI mock up.  I was trying to find you the actual MIX presentation as it is super cool to watch.  But here are some YouTube videos of that presentation from a user perspective I guess.
http://www.youtube.com/watch?v=zsAZjb7FKXA
http://www.youtube.com/watch?v=f3ErrS68YMM
Check it out!
update...found the SketchFlow video!!!  http://videos.visitmix.com/MIX09/C01F
Great keynote from there too: http://videos.visitmix.com/MIX09/KEY01
Comment: Sorry I think I didn't explain myself enough - When I mean sitemap I mean actual map of the site... Like a mindmap/brain storm?  Working out navigation structure, categories etc...
Comment: Yes...for that you want to use SketchFlow.  You can actually design a sitemap that works in real time.  Watch the SketchFlow video for an idea of what this entails...as it is super easy.
Answer: Maybe SketchFlow http://electricbeach.org/?p=145 ? which is included in the Expression Blend Trial http://www.microsoft.com/downloads/details.aspx?FamilyID=92E1DB7A-5D36-449B-8C6B-D25F078F3609&displaylang=en
Answer: I know this is an old question, but for others who find this via search, I personally love mocking my websites up with mind mapping tools. I've tried several but my favorite was MindNode for Mac and Xmind for Windows.
XMind free download:
http://www.xmind.net/
MindNode free download:
https://mindnode.com/
I've also tried MindMeister which works just as well as other mind mapping tools and is hosted for you so you can access your mind maps anywhere. However, MindMeister only allows you three maps (currently) without upgrading to a paid subscription.
Another that I've worked with is mockflow.com which is great for mocking up websites with all their features and buttons and even making clickable navigation. They have a free version, but again it's very limited without upgrading to a paid version.
Answer: I'm using Slickplan. This cloud based app allows me to have access to my projects from different machines regardless of their operating systems. All I need is one of the leading web browsers (Chrome, Firefox, Safari).
With Slickplan you can create visual sitemaps from scratch or you can use Site Crawler to import your existing website to visualize and reorganize its structure.
Of course you can always export your projects to the XML format, and use the exported file to create pages and menu systems inside some popular content management system - Slickplan provides plugins for WordPress, Joomla, concrete5 and a few more.


How do I know Tor does not publish my identifiable information in to the public?

Question: Can anyone tell me how and where can I check to make sure Tor is secured, without leak? And Tor does not publish my identifiable login information in to the public.
Comment: Your question is very broad at the moment and can be answered in different ways. So if you log in with your real name to some social network, your identity will of course leak. So could you narrow down the question?
Comment: I agree with @JensKubieziel; can you be more specific about what you're asking? Perhapse their is a specific facet of Tor's design that you'd like to know more about? As is, this question doesn't strike me as a "good fit" for this site.
Comment: Hi both, I mean does Tor can guarantee 100percent of leaking its users's identify? e.g. by using Tor to join IRC communicate with anonymous team, does people in IRC room could recognize where I'm coming from(IP address, Country etc.)?  Please let me know if you need more clarification than this.
Answer: One generally does not login to Tor to use the Tor network. In addition the use of Tor network is free of charge. Thus, there is no money trail to the user. If you turst any particular VPN, Web proxy, etc. you may use them to connect to Tor network to increase your level of assurance. But some pieces of advise to the wise:

Any VPN, Web proxy, etc. you use to connect to Tor network should be free, such that there is no money trail to you.
You should trust the web proxy, VPN, etc. to the point you entrust your anonymity to them. For example it should be your private VPN you have built for your own use.
You should make sure there is no malware on any of your systems.
You may use Whonix or Tails and if you know how to combine them, do so.
Do not run the hidden service from your home or office.
Do not use a relay and hidden service on the same system.
Do not do anything that if become public, ruin your reputation beyond repair, damage you financially beyond repair or cause the lose of your freedom for long period of time.

Happy Toring!


What is this Script Font?

Question: I cannot seem to find this, I was told by my client that its called "customised" but its no where to be found. Tried identifont and What the font, but its too complicated to break down.
Comment: Do you have any other examples of the font to compare individual letters to see if the letters are consistent or not? Looks like a font written using a tablet.
Comment: it is a font, the client wants to create a monogram for it, "CV" Customised Vehicles. But he doesn't have the font used.

Its not hand made. Its an edited font.
Comment: @AasimAzam if it's an edited font it's going to be very hard to detect. Is contacting the initial designer not an option?
Comment: Tried to contact him .... to no avail.
Answer: Xtreem Fat by Mans Greback via Myfonts

What is this Script Font?


Air transport of a MTB with hydraulic brakes

Question: I would like to transport my MTB on an airliner's cargo hold.
What are the requirements concerning hydraulic brakes, do they need to be flushed?
Comment: You have two possible issues -- the pressure changes and the possibility that the bike will be turned on end or upside-down.
Answer: Tires on planes are a problem because they are pressurized above sea level atmospheric pressure. The pressure on a commercial airliner drops below that at sea level, so the pressure difference increases which can exceed the pressure the tire can handle.
Hydraulic brake fluid is not pressurized above sea level atmospheric pressure and the brake system is designed to withstand high internal pressure when the levers are squeezed anyway.
Comment: We should clarify that some airlines *think* the tires are a problem, even though they are not. According to Jobst Brandt, Air France required his tires remain inflated to reduce the likelihood of passengers claiming damage to their rims (ref: https://yarchive.net/bike/air_transport.html)
Comment: What about the corrosiveness of the hydraulic fluid, is that not a concern for the carrier?
Comment: That would only be a problem for systems that use DOT 5.1 like SRAM. Shimano uses mineral oil. Brake fluid is not a great substance but it's no worse than the contents of many common batteries.
Answer: I flew with my MTB last year - no need to drain the hydraulics.
One thing you should do is get a couple of pad spacers to insert in the calipers whilst the wheels are out.
Answer: I've heard of airlines requesting that you deflate your tires, but I've never heard of people draining the hydraulic fluid from their brakes.
Two friends of mine recently flew from the US Pacific Northwest to US Southwest for a week-long mountain bike trip. They flew with their bikes as checked luggage. By their accounts, they did not need to deflate their tubeless tires (thankfully), their fork or shock, and they did not have to drain the fluid from their hydraulic brakes.


Structure entry with no URL

Question: I have an entries Channel with about 100 entries that I need to be able to custom order in CP.  Changing the channel to a structure seems to be a good potential solution for that.   I would also like to have some entries in a "featured" group and then the rest in an "archive" group that would be revealed by a load more button on the index.  Creating top level entries in the structure for "featured" and "archive" seems like it might be a good solution.   My question is, I don't want the "featured" or "archive" entries to have their own url pages (although I guess I could somehow forward them to the index page).  What's the best way to hide or forward these entry pages?   Or is there a better way to achieve the custom ordering.
Answer: I'd recommend to create two categories for that and just allow to assign one in the entries. That solves your url problem.
Comment: I thought of that, I would like to be able to sort without going into each individual entry to change the category.  I guess another option would be to leave it a channel section and then make a single section for the index page with a related "feature" field referencing the entries.  Then I could order and add or subtract the featured entries from there
Comment: Sure. On the other side, that's a one time work, I guess.
Comment: I'd agree with this answer. Too often I have seen Craft sites where the sections contain mixed data types, which causes a lot of pain during major site changes because the content was modelled based on the site design instead of the actual content semantics. Organise your content according to what it _is_, not what it looks like or where it goes in the design, and your future self will thank you. My standard sniff-test for whether to create hierarchical Structure sections: "Are these child entries a _more specific_ type of their parent?" If not, then generally relationships are better.

Structure entry with no URL


What does "Danger!" mean?

Question: During a Turf War I noticed a light-green "Danger!" prompt appear at the top of the screen next to my team's status icons. What does the Danger! prompt mean?
Answer: If it is still like that and Reddit is correct, that danger is that your team is getting led by 100 points or more.
Answer: My observation of some gameplay leads me to believe this appears next to your teams icons when you are losing by a significant margin.  In this gameplay video, you can see the opposing team has the Danger icon present, and when the score is revealed at the end, they lost by a significant amount.  From watching a few other videos, it seems to display when you have ~30% of the map covered or less, but I imagine it could be based off of some ratio between what your team has covered, and what the other team has covered.
Thus, if you see this symbol for your team, you better pull it together and make a comeback or you are going to lose!
Comment: The 30% figure seems inaccurate. I finished a game with the danger sign and had 38.4% vs 54.5%
Comment: @Stevoisiak that was more of just an observation - its probably somehow ratio based as I suggested.  It doesn't really matter though for the question at hand. 38% also isn't far off from ~30%

What does "Danger!" mean?


What are all the recipes obtainable from NPCs?

Question: I know there are some recipes that have to be obtained from NPCs since I got the Silver Sword recipe from an NPC in Port Puerto. Are there any other recipes that have to be unlocked before I can craft them?
Answer: This list is far too long to post as an answer, but there are some guidelines to follow if you want to make sure to be able to craft everything:

Talk to everyone with a question mark above their head, especially your life master.  These are NPCs that are associated with one of the lives that you have begun, and talking to them occasionally rewards you with an item, recipe, or task.  Sometimes this can be required to rank up!  Other NPCs don't give out recipes as far as I know.
Revisit these NPCs when you rank up.  Every time you rank up, the question marks will reappear above their head which means they have something new to say or give you.  These stack, so talk to these NPCs until the question mark is gone.  Since you won't lose anything and this process can take some time, you can wait a few ranks if you don't want to bother with it right away.
Enter every building in every town.  This can be a tiresome process, but sometimes an NPC associated with your life is in a shop associated with a different life.  If you do it enough, you will start to memorize where the NPCs are for your particular life and you won't need to waste time looking in places where you know they aren't.

Unfortunately, you can't get certain recipes until you reach the proper rank, so you can't just visit an NPC once and get everything you want from them.  However, most of the time the rewards aren't essential (sometimes you get nothing), so you can usually wait until you're a master to run around and grab stuff from everybody.
Answer: So far, the best place I found which lists recipes from NPCs is Wikia (e.g. Alchemist). From what I've seen, they don't yet list EVERYTHING, but have a pretty good list - specially for the NPCs. If you notice you're missing a recipe and it's not listed there, at least you can find the NPCs for that Life and try revisiting them to find the recipe!


Can I go back to my home country (Malaysia) with less than 1 month validity on my passport?

Question: My passport is expiring in one month and I am now planning to go back to my country, Malaysia. Can I travel back to my country with 1 month validity left on my passport? Should I take a direct flight or connecting? Please advise, thank you.
Answer: With one month or less, your passport is not valid anywhere for travel, except to your home country. A direct flight is safer – the airline can't refuse you boarding – but a connecting flight might work if the transfer happens completely airside, and you don't need a transit visa.
But why risk it? Fly direct.
Also, you might want to ask the Malaysian consulate whether you could renew your passport with them. It would solve the problem altogether.
Comment: There are plenty of countries (e.g. the UK) which allow travel so long as the passport is valid on departure.
Comment: Passport validity is also usually not an issue for airside transits almost anywhere.


SP 2016 Page with list of SiteCollections that users have access too

Question: So, I have a SharePoint 2016 on-prem site that has 10 site collections under it.  Different users have access to various site collections, and that is all handled in AD.  I'd like to set up the home page of the overall site and  display to each user the sites that have permissions to access. Is something like this possible?  Appreciate any pointers...
Comment: Do you mean that the main site collection is associeted to 10 additional site collections, or is it 10 sub sites?
Comment: Yes, a main site collection with 10 additional site collections under it.  On that main site collection, I then want the visitors to see links to the sites they have access to via an AD group.
Answer: Hello use Search Content Query Web-Part and as filter use contentclass:STS_Site. It will display all sites, but you know, search is using permission-based filtering, so users will see only Sites where they have permissions.
You'll probably need to filter Path to, cause they should be displayed unwanted Site Collections as MySites, so use Path:https://company.sharepoint.com/sites/*
MS Docs


BT wifi Internet router not detecting S9K miner

Question: I am mining crypto via GPU & ASIC miners. I recently bought an S9K Antminer which powers on perfectly fine; however as we all know, it needs to connect to the internet via an ethernet cable. This is where I have an issue.
When I connect my laptop or my GPU mining rig to my router via ethernet cable both devices are recognized on the router's 'BT Smart Hub' web interface, internet also works. However, when I connect my S9K to the router via ethernet the 'BT Smart Hub' web interface does not recognize nor detect the connection. I know its not the cable because of the examples above and because I attempted connecting the S9K to my GPU mining rig via ethernet cable and my computer recognized the connection straight away ( of course it had no internet, but still showed "Unidentified network via ethernet cable") I tried to call BT but the guy said unfortunately he has no expertise to address my issue, since I confirmed the router detected two other different devices (laptop / gpu mining rig) so he suggested I find an expert. Does anyone have any solutions?
Answer: Determine your home's private IP network information. It's likely somewhere in 192.168.x.y range, or perhaps 10.x.y.z
Antminer has instructions for determining the S9K's IP address (https://support.bitmain.com/hc/en-us/articles/360025765073-How-to-set-up-a-new-S9-SE-S9k) and to program its network and operating parameters.
It is likely the Antiminer is trying to get an IP address assigned  via DHCP; see if the router has an attached device list, possibly listing MAC addresses of attached devices. Antminers should have Bitmain's prefix, "E0-A5-09-xx-xx-xx". If you can see a device with a MAC address matching this prefix, that will be your S9K.
You may have to temporarily re-configure a laptop connected via ethernet directly to the Antminer to be able to access and reprogram the Antminer on a compatible browser to match your BT (British Telecom) router's private home network.


Using GDB in xcode 3.1.2 - what does 'error while running hook_stop:' mean?

Question: Pretty much a total newbie here, using xcode to write a c++ program.  I don't know how to use gdb yet and I'm not sure how you can turn it off..(if you can?)  Just added some openGL texture loading code and when I call it I get this error message in my console and the program freezes... what is happening?
Here's the code that throws the errors:
tex_2d = LoadTextureRAW("texture.raw", 0 );

GLuint LoadTextureRAW( const char * filename, int wrap )
{
GLuint texture;
int width, height;

FILE * file;

// open texture data
file = fopen( filename, "rb" );
if ( file == NULL ) return 0;

// allocate buffer
width = 256;
height = 256;
unsigned char *data = new unsigned char[256*256*3];

// read texture data
fread( data, width * height * 3, 1, file );
fclose( file );

// allocate a texture name
glGenTextures( 1, &texture );

// select our current texture
glBindTexture( GL_TEXTURE_2D, texture );

// select modulate to mix texture with color for shading
glTexEnvf( GL_TEXTURE_ENV, GL_TEXTURE_ENV_MODE, GL_MODULATE );

// when texture area is small, bilinear filter the closest mipmap
glTexParameterf( GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER,
                GL_LINEAR_MIPMAP_NEAREST );
// when texture area is large, bilinear filter the first mipmap
glTexParameterf( GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR );

// if wrap is true, the texture wraps over at the edges (repeat)
//       ... false, the texture ends at the edges (clamp)
glTexParameterf( GL_TEXTURE_2D, GL_TEXTURE_WRAP_S,
                wrap ? GL_REPEAT : GL_CLAMP );
glTexParameterf( GL_TEXTURE_2D, GL_TEXTURE_WRAP_T,
                wrap ? GL_REPEAT : GL_CLAMP );

// build our texture mipmaps
gluBuild2DMipmaps( GL_TEXTURE_2D, 3, width, height,
                  GL_RGB, GL_UNSIGNED_BYTE, data );

// free buffer
free( data );

return texture;

}
And here is the console output:
Loading program into debugger…
GNU gdb 6.3.50-20050815 (Apple version gdb-962) (Sat Jul 26 08:14:40 UTC 2008)
Copyright 2004 Free Software Foundation, Inc.
GDB is free software, covered by the GNU General Public License, and you are
welcome to change it and/or distribute copies of it under certain conditions.
Type "show copying" to see the conditions.
There is absolutely no warranty for GDB.  Type "show warranty" for details.
This GDB was configured as "i386-apple-darwin".Program loaded.
sharedlibrary apply-load-rules all
Attaching to program: `/Users/development/Desktop/devshit/smallermarkers/build/Debug copy/SimpleAR.app/Contents/MacOS/SimpleAR', process 1674.
Error while running hook_stop:
Error while running hook_stop:

Unable to disassemble glgConvertTo_32<GLGConverter_BGR8_ARGB8, (GLGMemory)2>.
(gdb)

I have come across this error before using precompiled libraries to load textures, so now I'm trying for the most simplistic route.  Anyone can clue me into this?  Googling the hook_stop doesnt seem to give alot of info :(
Answer: Take a look into your .gdbinit file, if you have a define named hook_stop it will get called before any define named stop. I just ran across this also, it is spelled out in the gdb manual:
20.2 User-defined command hooks
You may define hooks, which are a special kind of user-defined command. Whenever you run the command 'foo', if the user-defined command 'hook-foo' exists, it is executed (with no arguments) before that command.


Unable to install Image::ExifTool due to 'make test' hanging

Question: I have a Netgear ReadyNAS NV+ on which I'm trying to do some things using perl.
Since the perl installation from the vendor is compiled without the uselargefiles-flag I've tried to compile/install my own version to run in parallell with the system one.
When I first tried to compile perl on the machine itself I ran into trouble as the system is lacking alot of regular system tools which prevents the Configure-script from running properly.
# ./Configure -des -Dprefix=$HOME/perl-5.16.2
First let's make sure your kit is complete.  Checking...
./Configure: line 1986: split: command not found
cat: /root/dload/perl-5.16.2/UU/x??: No such file or directory
Locating common programs...
I don't know where 'comm' is, and my life depends on it.
Go find a public domain implementation or fix your PATH setting!

To get around that I installed and used this cross-compiler to build perl on another machine.
I could not figure out how to cross-compile using the standard configure-script from perl, so I used this.
After that I could just copy my new perl-folder onto the NAS and have thing like the following work:
# ~/sparc-perl-5.16.2/bin/perl -version

This is perl 5, version 16, subversion 2 (v5.16.2) built for sparc-linux

Copyright 1987-2012, Larry Wall

Perl may be copied only under the terms of either the Artistic License or the
GNU General Public License, which may be found in the Perl 5 source kit.

Complete documentation for Perl, including FAQ lists, should be found on
this system using "man perl" or "perldoc perl".  If you have access to the
Internet, point your browser at http://www.perl.org/, the Perl Home Page.

# ~/sparc-perl-5.16.2/bin/perl -e 'print "A string!\n";'
A string!

So in some sense I feel I've been successful in my quest to get "my" perl working on the machine.
I get in trouble when I try to install extra modules though.
I've tried installing Image::ExifTool using cpanp (among others), but the installation never finishes.
Today I resorted to trying the installation manually.
wget http://search.cpan.org/CPAN/authors/id/E/EX/EXIFTOOL/Image-ExifTool-9.12.tar.gz
tar xzf Image-ExifTool-9.12.tar.gz
cd Image-ExifTool-9.12
~/sparc-perl-5.16.2/bin/perl Makefile.pl
make

All work as they're supposed to.
when I get to make test however it hangs indefinitely like so:
# make test
PERL_DL_NONLAZY=1 /root/sparc-perl-5.16.2/bin/perl "-MExtUtils::Command::MM" "-e" "test_harness(0, 'blib/lib', 'blib/arch')" t/*.t t/AFCP.t ...........

Looking at the running processes I think these are the ones representing the command:
# ps aux | grep per[l]
root     26187  0.5  0.7 12000 7808 pts/0    S+   10:31   0:07 /root/sparc-perl-5.16.2/bin/perl -MExtUtils::Command::MM -e test_harness(0, 'blib/lib', 'blib/arch') t/AFCP.t t/AIFF.t t/APE.t t/ASF.t t/BigTIFF.t t/BMP.t t/CanonRaw.t t/Canon.t t/CanonVRD.t t/Casio.t t/DICOM.t t/DjVu.t t/DNG.t t/DV.t t/EXE.t t/ExifTool.t t/FLAC.t t/FlashPix.t t/Flash.t t/Font.t t/FotoStation.t t/FujiFilm.t t/Geotag.t t/GeoTiff.t t/GE.t t/GIF.t t/GIMP.t t/GPS.t t/HTML.t t/InDesign.t t/IPTC.t t/ITC.t t/Jpeg2000.t t/JVC.t t/Kodak.t t/KyoceraRaw.t t/Lang.t t/LNK.t t/M2TS.t t/Matroska.t t/MIE.t t/MIFF.t t/Minolta.t t/MP3.t t/MWG.t t/MXF.t t/Nikon.t t/Olympus.t t/OpenEXR.t t/Panasonic.t t/PDF.t t/Pentax.t t/PGF.t t/PhotoCD.t t/PhotoMechanic.t t/Photoshop.t t/PICT.t t/PNG.t t/PostScript.t t/PPM.t t/PSP.t t/QuickTime.t t/Radiance.t t/Real.t t/Ricoh.t t/RIFF.t t/RTF.t t/Sanyo.t t/Sigma.t t/Sony.t t/Unknown.t t/Vorbis.t t/Writer.t t/XMP.t t/ZIP.t
root     26189  1.7  0.0     0    0 pts/0    Z+   10:31   0:24 [perl] <defunct>

This is completely consistent with what happens when I try the same installation using cpanp.
I guess I could just run make install and hope that it won't be to much of a problem that the test is unable to run/complete, but that makes me feel a bit uneasy. I'd much rather figure out what is wrong.
I also find it odd that the test hangs the way it does, I could accept that it fails, but that it just keeps running in a non-productive manner feels weird.
Since it is the first time I've built perl from source and the first time I've used a cross-compiler I would not be surprised to learn I've done something very wrong, any help identifying what is very welcome.
What am I doing wrong?
EDIT - compiling on the mahcine:
Figured out how to get the Configure script working natively on the machine.
Will try to build there to see if that will work better. It'll take some time though, the machine is slow.
To be able to run the configure script I needed:
GCC
apt-get install libc6-dev gcc gdb libtag1-dev uuid-dev

coreutils
apt-get install coreutils

-Dcc=gcc
./Configure -des -Dprefix=$HOME/perl-5.16.2 -Dcc=gcc

EDIT2 - compile failed:
Most shortlived success ever:
# make
`sh  cflags "optimize='-O2'" perlmini.o`  -DPERL_IS_MINIPERL -DPERL_EXTERNAL_GLOB perlmini.c
  CCCMD =  gcc -DPERL_CORE -c -fno-strict-aliasing -pipe -I/usr/local/include -D_LARGEFILE_SOURCE -D_FILE_OFFSET_BITS=64  -O2 -Wall
In file included from perl.c:33:
perl.h:699: error: conflicting types for `syscall'
/usr/include/unistd.h:939: error: previous declaration of `syscall'
ake: *** [perlmini.o] Error 1

EDIT3 - testdriving fork:
Tried the following to verify that fork works as it should. I believe that the test is successful, but I've never tried fork before, so please let me know if I read the output wrong.
# cat test_forkwait.px
#!/root/sparc-perl-5.16.2/bin/perl

$pid = fork();
die if $pid < 0;

$SIG{CHLD} = sub { warn "SIGCHLD\n"; };

if($pid) {
    $status = waitpid($pid, 0);
    warn "wait status: $status\n";
} else {
    warn "Child starting\n";
    sleep 1;
    warn "Child terminating\n";
}

# ./test_forkwait.px
Child starting
Child terminating
SIGCHLD
wait status: 29913

Answer: I'm a bit late with this comment, and don't have any ideas about your "make test" hang, but I wanted to point out the Image::ExifTool is pure Perl, so it does not require compilation.  The install step is as simple as copying the distribution files to the proper directories.

Phil
Answer: Gave up on figuring out why the test fails. Ended up using the module anyways. Seems to work OK with my files.


A browser addon that makes a box pop up in the corner on certain domains

Question: I want to create an addon where when you open a webpage from certain domains, a square or circle (not sure which yet) image will pop up on the corner of the page.
The closest example I can think of is the GetGlue addon. When you are on a page from specific domains, the toolbar pops up on the bottom and gives you options to pursue while you are on the page. Then once you go to a non-supported website, the toolbar is gone.
However the one I want to create is much more simpler where I just want an image to show up in the top corner of the page when you arrive at certain webpages, and disappear once you move to a domain not supported. It's not going to do anything or link anywhere or have any actions; it's just an image.
I don't know much about creating addons, but I am willing to learn how to do so as creating this is of somewhat importance to me. But I've been looking around, and I've come across things to get people started on creating them, but I don't really know how to go about it as I've not sure how I can get what I want done, and the ones I see are about things not related.
If anyone knows of any guides or tuts or anything similar that can explain the basics or even some more in-depth of doing what I want done, many thanks are sent your way.
Answer: Look into content scripts
This allows you to inject JS and CSS into any page that matches a url pattern
For example, including the following in your manifest will insert mystyles.css into any page under http://www.google.com/
<code>"content_scripts": [
    {
       "matches": ["http://www.google.com/*"],
       "css": ["mystyles.css"]
    }
],
</code>


how can I map a shortcut to an arbitrary key sequence in xmonad or xwindows?

Question: I have a shortcut I would like to perform on any chrome instances whilst using xmonad (or a generic xwindows solution would be handy)
basically its the same keysequence for chrome/firefox/opera to "detatch current browser tab and send to screen n"
The pseudocode
<code>//detach current tab and send to screen n
if current_window_is_browser
     map <alt-t>6 <ctrl-l><ctrl-c><ctrl-w><ctrl-n><ctrl-v><enter><alt-shift-6>
</code>
I've fooled around with tab detach scripts but they don's seem to be current (esp chrome). At any rate I want the same command for all of the browsers.
Any ideas? Cheers
Answer: You might want to have a look at xdotool
Install via apt: sudo apt-get install xdotool
with xdotool you can do:
<code>xdotool key alt+t 6 ...
</code>
of course you could save the xdotool as a script and execute it with a keybinding in xmonad.


How to extract one icon from an icon grid .eps file (a pack of icons) using Adobe Illustrator

Question: I have been trying to figure this out for the last hour, but have not been able to yet. I am pretty sure this is a very basic operation.  Can anyone provide me the url to a basic tutorial or just the steps?  I just need to extract one icon from the grid of icons (pack of icons) that I just purchased and save it as a .png file so I can customize it with Adobe Photoshop.
Comment: If this is an eps file, it should be entirely editable? Make sure the layers are not locked.
Answer: Use the Direct Selection Tool (the white arrow) to click-drag around one icon. Then Edit > Copy, File > New, Edit > Paste, File > Save As....
Comment: Thank you so much(:  This was driving me absolutely batty!  It works quite well.


Cloudfoundry how to let two apps sharing one database service

Question: I bind a postgresql service for two apps. They both update the database. Problem is that I use one of the app to create the tables(database schema) by using spring jdbc namespace. But since the other one is provisioned to use a different user name and password. It can not access the tables created by another one. Anyway cloudfoundry to provide the flexibility to resolve the issue?
Comment: The two bindings should use the same user and password (which, BTW, you should not care about). Can you share a bit of your `` config, just to make sure you're not doing something crazy?
Comment:
Comment: And I am pretty sure the username and password are different for each binding. I printed the VCAP services environment variables and they are using different username and password.
Comment: Hmmm, you're right about the username/password being different. The database name is the same though, and so my understanding is that this should be working (the intent is indeed to have apps collaborate using shared services). If you can't make this to work, I suggest opening an issue.
Answer: For Spring apps, this can be achieved by taking the advantage of "auto-reconfigure". CF detects the bean of class javax.sql.DataSource under certain conditions and then replace the properties such as username or password with values of provisioned ones. You can find very detailed instructions here: http://docs.cloudfoundry.com/frameworks/java/spring/spring.html
Therefore for your 2 apps you can both configure the datasource connection as the same format. As long as you bind the same postgresql service to these 2 apps, although CF will inject different values to both apps, they can access same table without any explicit configurations.


Can't rename world after adding "color"

Question: I decided to rename my world in color but then I accidentally pressed backspace so I went to type it in again and it won't let me. I have no idea what to do and it was my favorite world. I DONT WANT TO LEAVE IT NAME LESS. Any suggestions? I also don't want to delete that world or delete minecraft because I have spent so much time on it. Thanks
Comment: Renaming the folder would give you that small name under your bigger name. You can also duplicate and rename your world. I am also trying to experiment with the `level.dat` file that every world has. Will come back with results
Comment: I saw your answer post. Please avoid posting non-answer content as it is intended for answers only. Instead, comment. You need 50 rep for other posts, but you can comment on yours and I think my answer too. Anyway, If you have access to the game's saves, you can
Answer: You can edit the name of your world after applied changes with an NBT editor like NBTEdit or NBTExplorer.
This is how you would do it for NBT explorer:
Open up your NBT Explorer and navigate to the level.dat file in your save folder.

You will see many options for your world. Here, you scroll down to the Level Name tag, and edit it with the EDIT option on the top.

Then you can save, and also rename your world folder (the one inside saves) so you have the gray name on the bottom also. I did not test this, but I think you can use color codes in here too.
\00002A\This is Blue

Comment: I forgot to mention that this glitch is on mine raft PE. Would your solution still work?
Comment: It should, as long as you have access to some sort of level.dat on minecraft PE. Perhaps make a backup and download it to your PC

Can't rename world after adding "color"


How do you run a SSH server on Mac OS X?

Question: How do you run a ssh server on Mac OS X?
Answer: Go to System Preferences -> Sharing, enable Remote Login.
Comment: sudo systemsetup -setremotelogin on
Comment: ... and make sure the user is included in "Allow access for" -.-
Answer: In System Preferences under Sharing, there is an option for Remote Login.
This will run sshd at startup (through launchd) and enable SSH access with standard options.  To tweak the sshd options, edit /etc/sshd_config (or /private/etc/ssh/sshd_config in later versions) (you'll need to do this in a sudo shell or via sudo vi /etc/sshd_config).
Comment: OpenSSH `sshd_config` file is in `/etc/ssh/sshd_config`, never see it in `/etc` on any Linux distro or UNIX-like systems.
Comment: Unfortunately, that config file won't allow you to edit the port used. To change the port, see http://serverfault.com/a/67616/102900.
Comment: To restart ssh, turn Remote login off, and then turn it back on. No restart is required.
Answer: I'd prefer:
sudo systemsetup -setremotelogin on

Comment: `Turning Remote Login on or off requires Full Disk Access privileges`
Answer: To provide a full answer for users who prefer a terminal¹ solution:
sudo systemsetup -setremotelogin on

When you receive the following error message:

Turning Remote Login on or off requires Full Disk Access privileges

Go to Settings > Security & Privacy > Privacy > Full Disk Access; then select Applications > Utilities > Terminal from the file picker². Then execute the command again, it should be in the history so you might just need to press arrow upwards.
You should be able to login with your password, but you should configure SSH key based authentication instead and/or add 2FA. Not sure how to do this on the Mac right now³.
Relevant links:

Apple: Use the systemsetup command-line utility on macOS Catalina 10.15
Ask different: Is there command to grant Full Disk Access for specific application?
Ask different: macOS: List apps authorized for full disk access

Not a terminal only solution at the moment and I am a first time Mac user. Wondering why this is not on Ask different, oh it's from 2010, that my be the reason why.
I see the need for improving security, but the ways of thinking and navigating around the user interface (and getting things done) is not really an improvement over Windows for me as a Linux user. Sure everything looks very nice, but to get things done the people I work among install brew and GNU tools... to praise the Mac for it's software quality? Oh come on. I really expected more.
It works on the Mac VM I set up with Quickemu to play around there before breaking my employers Mac accidentally.


translate menu item using entity translation

Question: I am kind of confused and really need some guidance
Is there a way to translate menu items using entity translation?(One item for all languages)
Thanks
Comment: i am aware of that option but when I translate my menu items I end up getting more than one link per menu items depending on how many languages are enabled.
Comment: Please read the document I have posted "LINK"
Answer: With Drupal core alone, user-defined menu items are not translatable. The Menu translation module, part of the i18n package, allows users to select a translation mode for each menu.
LINK
Comment: would'nt this way produce multiple menu items?
Comment: @redamakarem why bother if each copy is only visible in it's language?
Comment: i have lots of menu items with 3 to 4 levels so there will be loads of them. I just wanted to know if there was a way thats all
Answer: Use the entity_translation_i18n_menu submodule of Entity translation.

Allows menu items to be translated on the entity form.

It has good integration with the i18n_menu module.


what am i missing ... why run a S/390 platform with Fedora desktop?

Question: I found this link for a group that is converting fedora RPM's to run on S/390 hardware. Wikipedia tells me that the S/390 was made by IBM as a mainframe computer in the 1990's (and run out of service before 2000). So I have two questions: Why would you run a "standard desktop" OS on a (deprecated) mainframe? and are there any practical applications for a 1990's mainframe nowadays? The site seems to be pretty active, so I feel I must be missing something in its purpose.
Answer: Like most distributions, Fedora is not really only a 'desktop' OS - it is a 'server' OS as well. It depends on what packages you install since in the repositories are both desktop and server applications available.
Thus, I guess that you want to use Fedora on S390 for server stuff (mainframes are advertised for their IO performance/throughput, batch processing, right?).
As with other vintage hardware there are probably three major reasons to run Linux on it:

Because you can, as a hobby project, to learn something about porting, the hardware
Because you don't have the money to buy new hardware
You want to interface with a proprietary subsystem you don't want/can't replace yet.

How active the Fedora s390 project is I don't know. I mean, some packages you care about you have to port, but other portable software just need to be recompiled and once a buildserver is configured for yet another architecture, new incoming packages are automatically built.
Comment: Thanks for good explanation... I definitely understand that Fedora can run those things. It just looked to me like the site was converting the breadth of the fedora repo library, from games to media players to guis to server apps. My point was that it seemed like the site had a good number of users converting the RPM's and submitting them, and it seemed like a bit more than a hobby project. I had never even heard of the S/390 Architecture (not thought  that my knowledge is very deep in that regard). I just though was missing something with the hardware.
Answer: Wikipedia also notes:

z/Architecture retains backward compatibility with previous 32-bit-data/31-bit-addressing architecture ESA/390 and its predecessors all the way back to the 32-bit-data/24-bit-addressing System/360.


Is there an OCR that can convert an image of a formula into a TeX markup?

Question: Is there an OCR software that can convert a graphical image (in PNG, GIF, TIFF, PDF... format) of a mathematical formula into the corresponding TeX markup?
Answer: Yes. There is one that I knew.

More details, see this link.
Comment: The correct link to FFES (Freehand Formula Entry System) is https://www.cs.rit.edu/~rlaz/ffes/
Comment: There's also FFES (http://www.cs.queensu.ca/drl/ffes/), which along w/ Infty is mentioned at: http://www.tug.org/interest.html
Answer: The Mathpix app can convert pictures of printed and handwritten math and convert it to LaTex. The new Mathpix desktop app that was recently released lets you take a screenshot of the equation on your desktop and copies the LaTex to the clipboard so you can just paste it into your LaTex/markdown editor.
Comment: @iMath Hi, and thank you for your comment. I have tried the online version but my humble opinion is that you can not copy many formulas but only some equations. Now I delete my old comment.
Comment: It is also a Desktop app which takes screenshots and copies Latex to clipboard
Comment: @Sebastiano They also provide online version right now https://snip.mathpix.com/redstone-cold/notes/note-1/edit


Install psycopg2 for Anaconda Python

Question: I have Anaconda Python 3.4, however whenever I run older code I switch to Anaconda Python 2.7 by typing "source activate python2". My issue is that I have psycopg2 installed for Anaconda Python 3.4, but not for Anaconda Python 2.7. When I run pip install psycopg2 (on Python 2.7) I get the following message:
Error: pg_config executable not found.
Please add the directory containing pg_config to the PATH
or specify the full executable path with the option:
    python setup.py build_ext --pg-config /path/to/pg_config build ...
or with the pg_config option in 'setup.cfg'.

I am fairly new to programming and need help in:
1. Obtaining directory containing pg_config
2. Finding the path to Anaconda Python 2.7
3. Adding pg_config to the PATH.

After I complete these steps I should be able to pip install Install psycopg2
Answer: If you have anaconda, you can sidestep some of these headaches.
You said you have the Anaconda distribution of python and a quick look at the included packages shows that psycopg2 is already there (although not in the installer). You can simply:
source activate python2
conda install psycopg2

This allows the conda installer to manage all of the binary dependencies.  Also makes it easier to upgrade.
If that does not work or there are reasons for not liking that package  (version issues?) then that is a different question.
Comment: this is the right way. pip seems to have a hard time knowing what to do with conda envs. repeated attempts to `pip install psycopg2-binary` in various ways (such as python package builds) failed, but just using the conda install did it.
Answer: You need development system package for PostgreSQL which contains header files required to compile psycopg2 extension. For my CentOS 64 bit the command to install is:
yum install postgresql-devel.x86_64

but it depends on the OS - for Ubuntu that would be apt-get install ... - the name of the package varies slightly between distros.
Steps 2 and 3 should be unnecessary after you do this.
EDIT: For Mac OS that would be just:
brew install postgresql

as written here
Comment: Since yum and apt-get are not on MAC OS, I tried:  brew install postgresql-devel.x86_64   ... no luck. Error: No available formula for postgresql-devel.x86_64
Answer: As OP is using Anaconda, if one wants to install psycopg2, open CMD.exe Prompt for the environment that one will be working on and run
conda install -c anaconda psycopg2

# or

conda install psycopg2

(Source)
If one wants to install psycopg2-binary, then use
conda install -c conda-forge psycopg2-binary

# or

conda install psycopg2-binary

(Source)

Notes:

If the above didn't work, consider using pip as follows:

pip install psycopg2 (Source)

pip install psycopg2-binary (Source)

Note, however, that pip doesn't manage dependencies the same way conda does and can, potentially, damage one's installation.
Answer: env is the virtual environment created on Anaconda
once env is activated, type this in the terminal :
conda install -n env [package]

eg.
$ conda install -n env psycopg2

After this type python to enter the Anaconda shell, and then type:
import psycopg2

If it shows no error, it has successfully been installed.
Answer: I downloaded anaconda and looks like i have access to pip3
pip3 install psycopg2

Install psycopg2 for Anaconda Python


How do I add print button in Joomla list view.?

Question: I have created my business logic in model, but in view part I'm not so expert of how to use JHTML.
Can anyone tell me how can I add a print button in joomla list view?
Comment: What have you tried so far? Have you looked at com_content to see how it's done?
Answer: I don't know if you talk about the frontend or backend... if you are in the Joomla! backend you can create a custom toolbar button in your view.html.php
$bar = & JToolBar::getInstance('toolbar');

$bar->appendButton( 'Print', 'print32', 'Print', 'index.php?option=com_yourcomponent&view=yourviewname&tmpl=component&print=1' );
The second argument is an image if you want a custom image you need to add extra styles in a css file:
.icon-32-print32 {
    background-image: url(../images/print32.png);

}
In your view check for the print variable in the url and put a button if present, for example:
<?php if(JRequest::getVar('print', 0, 'get') == 1) : ?>Click for Printing<?php endif; ?>

The toolbar button opens your list without the joomla template but check if your admin template has a component.php file in the template root.
If you are in the frontend check this explanation in the Joomla! Docs https://docs.joomla.org/Adding_print_pop-up_functionality_to_a_component
Comment: yes i'm talking about back-end and yes thanks


What determines domain value?

Question: I want to buy a domain but everywhere I go they tell me that domain costs $ 4000 who or what determines the value of this domain and why is it so high?
Comment: that is not true for new domains, I think your are trying to buy an old domain, instead buy a new domain you can get at very cheap rate everywhere try  godaddy.com, one.com. ....
Comment: @Bala it says that domain was created 2003 and is owned by buydomains.com, so that means they purchased it and now are selling for that price?
Answer: If it is a premium domain, then yes, it will be worth $4000. An example of that is exda.com, which I wanted to buy. I on the .org version for $10 a year. As for a description, from Google, they say:

A Premium Domain is a domain name that is already registered and owned by someone, but made available for sale. Prices for Premium Domains range from a few hundred to a few thousand dollars depending on the specific domain and current market influences.

A few other requirements that make a domain premium is:

Short names and acronyms
Ussually .com or a domain like date.me
One-word or brandable names
Domains with high traffic and search volume

You could try the .net, or .org version of the domain which you want, than maybe you can get that instead of the actual one you are looking for. The reason why I am saying this is because, by the question, you do not have the $4000 to pay for the one you really want.
Comment: You are correct I do not have that amount of money at this time, and I just wanted to make sure that it is not a scam.

What determines domain value?