Python - How to ignore white spaces in double quotes while splitting a string?
Split a string by spaces -- preserving quoted substrings -- in Python
What would be the material or shaders node set up for a smooth gem in blender cycles engine?  I want a result similar to this image: Is copper piping required within a certain distance from a water heater? I have read that National Code requires you to use copper for 18 inches from your water heater.  How can I do this when everything existing is PEX?   I need to replace my existing low boy water heater next to my kitchen sink.  It was installed by the builder ten years ago. All the pipe in the house is PEX.  The existing water heater is connected using PEX as well.    The supply line comes directly thru the wall to the HW Heater. There is no space to run 18 inches of copper! The heater is under the kitchen counter, and the countertop is directly over it. Only about an inch clearance. @username auto-completion for comments was , and is already active on MSO.  However, it only seems to auto-complete the usernames of people who have commented on the post. According to , the list of users who can be explicitly notified also includes:   Anyone who edited the post Anyone who started a bounty on the question The &diams; moderator or  who cast a binding close vote on the question   Why not auto-complete those, as well? How do I stop friends from getting notifications about what I do on Facebook? Friends and family (who are not in my Close Friends group) are getting notifications when I post or like something on Facebook. How do I stop this? Updating entities in response to collisions - should this be in the collision-detection class or in the entity-updater class? I wish to print a Stack&lt;Integer&gt; object as nicely as the Eclipse debugger does (i.e. [1,2,3...]) but printing it with out = "output:" + stack doesn't return this nice result.  Just to clarify, I'm talking about Java's built-in collection so I can't override its toString().  How can I get a nice printable version of the stack? The text of the  spell reads:      A flickering flame appears in your hand. The flame remains there for the duration and harms neither you nor your equipment. The flame sheds bright light in a 10-foot radius and dim light for an additional 10 feet. The spell ends if you dismiss it as an action or if you cast it again.   Emphasis mine. The druid in our party asked our DM if he is able to cast produce flame in a dark cave, then opt not to attack with it, and wield a shield and sword. The goal is to continue emitting light, since he doesn't have the light spell. He claims that since the flame does not harm his equipment, he is able to hold a shield or sword with the fiery hand with no problem.  Is this okay to do RAW, or are we missing something?  This is specifically not asking about casting spells with a sword in hand. He wants to draw his weapon after casting and holding the flames.  Related, but not the same question: , , . Nicely force 66 characters per line Currently, the only way to ask for something to be migrated to a site that isn't part of the standard migration path is through a custom mod note.  I currently have two active custom mod notes on Stack Overflow that ask for migration that are not standard targets for SO.  I believe the questions could be better answered on another site.  Fortunately, or unfortunately, the questions have been answered, and answers have been up voted and accepted. At this point, a week and a half later, migrating either of the questions would be disruptive to both communities and not necessarily produce a better answer (they've got accepted answers).  The unfortunate part is I really do believe that both questions could have gotten better answers and more attention on another site.  What I would like to see is a more streamlined way to flag for moderator attention for migrations.  The UI would look something like this:    This would allow people to find the proper site easily.  No more "Migrate this to Mathamatica.SE" because, well, that doesn't exist.  Something that I didn't do on this mock up is add a link to the corresponding help/on-topic page for the target site.  Something people could check and click before hitting the submit button.  I don't have this quite right again, because while that shows a "closing for off topic", this is a flag and not a vote to close.    The "flag for migration" is only one part of this though.  The other part would be to make another flag queue style thingy for moderators in which they could look at just migration flags created through the above interface.  By providing the mods with a "just migration" view into the flags, questions that should be migrated can be quickly identified from the multitude of existing flags and handled promptly before the migration would be disruptive. Kronecker delta confusion I'm confused about the Kronecker delta. In the context of four-dimensional spacetime, multiplying the metric tensor by its inverse, I've seen (where the upstairs and downstairs indices are the same):  $$g^{\mu\nu}g_{\mu\nu}=\delta_{\nu}^{\nu}=\delta_{0}^{0}+\delta_{1}^{1}+\delta_{2}^{2}+\delta_{3}^{3}=1+1+1+1=4.$$  But I've also seen (where the upstairs and downstairs indices are different):  $$g^{\mu\nu}g_{\nu\lambda}=\delta_{\lambda}^{\mu}=\left(\begin{array}{cccc} 1 &amp; 0 &amp; 0 &amp; 0\\ 0 &amp; 1 &amp; 0 &amp; 0\\ 0 &amp; 0 &amp; 1 &amp; 0\\ 0 &amp; 0 &amp; 0 &amp; 1 \end{array}\right).$$  How can there be two different answers to (what appears to me to be) the same operation, ie multiplying the metric tensor by its inverse? Apologies if I've got this completely wrong. Can Windows use a Linux shell instead of cmd? I was wondering if it is somehow technologically possible for Windows to add some sort of Linux interface?  I think it would win over many programmers to develop on Windows.  Any ideas on this? What's with the Japanese SO's stats? Induction Proof: Fibonacci Numbers Identity with Sum of Two Squares Prove $f(S \cup T) = f(S) \cup f(T)$ This option, which was present in the "Mouse and Touchpad" settings panel in previous versions, is for some reason absent in 16.04 LTS. Does anyone know why this is, and/or how to fix it? Thanks. I've just happened to read this  on MO (that of course has been closed) and some of the answers to a similar  on MSE.   I know almost nothing of nonstandard analysis and was asking myself if something like the sentence « $1- 0.999 \dots$ is a nonzero positive infinitesimal» could be easily expressed and proved in nonstandard analysis.  First of all, what is 0.999... ? If we take the usual definition as a series or as a limit of a sequence of rationals, then it will still be a real number and equal to $1$ (I guess by "transfer principle", but please correct me if I'm wrong).  Instead, let's define  $$0.9_N:=\sum_{i=1}^N 9\cdot 10^{-i} $$  where $N\in{}^*\mathbb{N}\setminus\mathbb{N}$ is an infinite nonstandard natural number. This $0.9_N$ is a legitimate element of ${}^*\mathbb{R}$, expressed as $0.$ followed by an infinite number of "$9$" digits.  What can be said about $\epsilon_N:=1-0.9_N$ ? Is there an elementary proof that $\epsilon_N$ is a positive infinitesimal of ${}^*\mathbb{R}$ ? (by "elementary" I mean just order and field axioms and the intuitive facts about infinitesimals, like that for $x$ infinite $1/x$ is infinitesimal etc.; no nonprincipal ultrafilters &amp; C). Could one fire a bullet with sufficient speed to leave the Earth? How can one find the zeroes of $f(x)=ae^{bx}+cx+d$? A certain physics problem I have been working on has turned into a math problem. Particularly, I want to find the solutions of some equation of the form   $$f(x)=ae^{bx}+cx+d = 0$$  where $a, b, c,$ and $d$ are constant, real numbers that come from the physics problem and $x$ will be a real number. I do not know how to find the solutions of an equation of this form. In the special case where $c=0$, the solution is simply  $$x = \frac{\ln(\frac{-d}{a})}{b}$$  but for other values of $c$, I am stumped. If there is no exact form for the roots, is there a relatively simple way to estimate the roots? How do I take a screenshot on my Mac? What's the easiest way to take a screenshot of my Mac?  I've used Grab.app, but it's a bit annoying just to get a quick screenshot. Is there a faster way? I have noticed a couple of kinds of behavior that seem to crop up in the SO community, and it really seems to artificially boost reputation. There may not be a solution (or it may not be a problem!) but here are some thoughts.  The first is the fact that "celebrity" users, or users with lots of reputation, are treated significantly better than others. Take Joel Spolsky's most recent question:    It was closed, opened, closed, and re-opened. And the question has earned Joel - what - 1030 reputation 103 votes, and lots of reputation! Wow! I'm not saying that Joel's question is a bad one. But lets compare to other questions that one might consider to be in the same equivalence class - easily answerable, specific questions, short questions:   (5 votes)   (5 votes)  If you look at the , I can hardly find any which are specific technical questions. So that Joel's question was so upvoted could only mean that:   It was upvoted based on his celebrity People have been interpreting the questions as a sort of zen-like wakeup call, designed to get people talking and thinking about they way they vote.   I do not mean any disrespect toward Joel, and again, I think his question was a good one. This post isn't about Joel! But the boost in reputation did not (imho) mean "Joel is really good at programming, and he has earned my trust as someone knowledgeable about computers." It may be true that Joel is a proficient computer expert, but not based on the merit of that one question.  Which leads me to an example about myself. I recently gave  (130 reputation) to a question about PHP's image-creating libraries. I am very appreciative of the community's support for my answer - an answer which I believe was well-thought and that I put effort into.  At the same time I can't look someone and tell them, with a straight face, that my reputation is a great reflection of my computer-related knowledge. Billions of people on the net have created tutorials for PHP's GD image library - I just happened to be the person to post a few of them. Heck if I know why it got 13 votes! (oh, but please don't downvote it!!)  SO is built by the community - so the community absolutely gets to decide what questions are important, and how they choose to dispense reputation. But in practice, I feel like peoples' reputation would be much lower if the community were more discriminating about the way they voted.  So: am I totally off base here? Is this even something that can be corrected with a different reputation algorithm? Or am I the only one who sees this as a detriment to the SO community?  (And, to be completely clear, I do not intend for this to be an ad hominem, and I am not jealous about not having a higher reputation. But I do take reputation with a grain of salt, in part for these reasons, and I thought I'd bring it up! It is meta, after all!)