python:  m=[[0]*3]*2 for i in range(3):     m[0][i]=1  print m   I expect that this code should print  [[1, 1, 1], [0, 0, 0]]   but it prints  [[1, 1, 1], [1, 1, 1]]
I needed to create a list of lists in Python, so I typed the following: my_list = [[1] * 4] * 3  The list looked like this: [[1, 1, 1, 1], [1, 1, 1, 1], [1, 1, 1, 1]]    Then I changed one of the innermost values: my_list[0][0] = 5  Now my list looks like this: [[5, 1, 1, 1], [5, 1, 1, 1], [5, 1, 1, 1]]    which is not what I wanted or expected. Can someone please explain what's going on, and how to get around it?
Here is what it looks like in Blender Render (Not Cycles).   This is how I set it up.   Basically, I'm trying to export it, but it's not including the &quot;Freestyle&quot; lines. When I open up the .dae file in Finder, it looks like this:   What is wrong here? I want it to be exported (COLLIDA .dae) with the black outline. I'm seeming to think that maybe the &quot;Freestyle&quot; is only for the Blender Render. Am I right? How would I go about getting the black outline included in my exported model? Is it an export setting I have to tick? Thanks for any helpful answers. This post is an expansion of  For many graduated sites (eg Physics), moderators do not want to apply the unilateral close vote in all cases--it is better to let some community votes pile on first.  We only use the unilateral in obvious cases then. This renders the CV queue useless to us. If we &quot;skip&quot; something, we can't get back to it. If we say &quot;do not close&quot;, it's removed from the queue and our community can't see it. If we use &quot;close&quot;, we are using a unilateral mod vote--we don't want to do that. What I propose is a set of &quot;next/previous&quot; buttons, that let us navigate the queues, looking for closeable questions, and coming back to the others later. Thoughts? Update and bounty reason Due to the recent Great Flag Overhaul, mods no longer see close flags in the flag queue. Which means that the only way to get to them is via the review queue 1 Shog's solution is ideal in this case; let mods view the close queue as a list. (In fact, a list similar to the old flag queue -- which shows a list of mods who have seen the post and what mod actions have already been taken -- would be great) On Physics, the majority of the flags that we get are VTC flags. And the community isn't always able to close things on their own, so we have to step in. However, powering through the close queue isn't an option; because &quot;skip&quot;ing a post2 leads to it being dumped into the void (I can't get back to it unless I have a link). Extremely inconvenient. Could the workflow here be improved? 1. The /tools listing for posts with outstanding close votes doesn't work because it doesn't list posts which have been flagged but not VTCd 2. which I may want to take a closer look at later; gotta be careful with the binding votes. I think this was more of a fantasy series, though it was more subtle than The Lord of the Rings IIRC. Set in modern times - though there was some alternate realm thing that was less modern I think.   I read it about ten years ago, I think, and there were a number of books at that time. My brother and I stopped reading it shortly after the main character summoned a small demon somehow who was a bad influence... I think.  It involved a boy who somehow was at some kind of training school/academy. Unsure where it was located, but it needed a classic portal to get to it I think. I clearly remember some scene involving a car driving at specific speeds to get past some barriers. There may have been something about how the school was (slowly) moving or the wards were shrinking... unsure. I don't think it was only magic based, but that was some element of it. The boy had some kind of strange power that made him an incredible fighter, but he wasn't sure how (at least from what I remember). The recordings of him training just showed a white flash I think. I remember some scene in an elevator going down to the training floor where he went to a level below some adult with him.  There was something else about him joining a group that had twelve members, one for each month, whose powers grew and lessened based on how close the date was to "their" month.  Oh, and there was something about him looking for his mother I think? Perhaps in another "realm"?   Any help is appreciated! .NET Process.Start default directory? I'm firing off a Java application from inside of a C#  console application. It works fine for the case where the Java application doesn't care what the "default" directory is, but fails for a Java application that only searches the current directory for support files.  Is there a process parameter that can be set to specify the default directory that a process is started in? How do I fix my locale issue? Why I can't connect to VPS after changing OS from CentOS to Ubuntu? Word for seeing both sides of an argument How can I create a video file from a set of jpg images? Do you pluralize the singular possessions of / items or people associated with individual members of a plural group? How can I make Windows Paint save by default as JPEG format? anyone tell how is this effect created which change lips color to orange and little orange on face without brush etc tool how to change the only lips color to orange without brush etc tool and how this is created and little orange on face How to find out who deleted some data SQL Server My boss had a query from a customer yesterday asking how they could find out who deleted some data in their SQL Server database (it is the express edition if that matters).  I thought this could be found from the transaction log (providing it hadn't been truncated) - is this correct? And if so how do you actually go about finding this information out? What happens with the force of gravity when the distance between two objects is 0? so I had my first approximation to the gravity equation  \begin{equation} F=GmM/r^2 \end{equation} and some questions arose that my teacher couldnt respond: if r approximates to 0 with mM being constant, then the force should tend to infinity, right? so that being true, then if we would travel to the center of the earth, we would be crushed by gravity? if so, how can there be anything right in the center of the earth? wouldnt anything there be compressed and destroyed by the infinite force?  having that in mind, my next question is as gravity force is measured from the center of an object, any part of the same object which is not at the center would be affected by the same object's gravity? if so, how can we differentiate between two objects that are not in a vacuum? my question originated thinking in us standing on the earth, in contact with it, are we, in a gravitational sense, one object? this lead to the last question, if gravity is a property of matter, then how applying the same logic as before, how does it work between two neutrons?(chose neutrons because i assumed it would be more difficult obtaining gravitational force if there was electrostatic forces from charges inbetween) do two newtrons in contact count as 1 gravitational object? and how thats its own gravity affect the newtron from center and out? In The Witness, I was walking along the coast, and I came upon this:    Now, since I've learned      that mazes can be embedded in the environment,   I see the puzzle here, but I just can't get the pieces to line up well enough.  Standing on the couch and walking all around it doesn't seem to get me a       functional maze.   Where do I need to stand to activate the puzzle successfully? How to get dark menu bar and dock in Mojave light mode? I prefer light windows with dark menu bar as in High Sierra. However, it seems I can only choose all-dark or all-light in Mojave now. Are there any way to hybrid or customize it? I have a (symmetric) matrix M that represents the distance between each pair of nodes. For example,       A   B   C   D   E   F   G   H   I   J   K   L A   0  20  20  20  40  60  60  60 100 120 120 120 B  20   0  20  20  60  80  80  80 120 140 140 140 C  20  20   0  20  60  80  80  80 120 140 140 140 D  20  20  20   0  60  80  80  80 120 140 140 140 E  40  60  60  60   0  20  20  20  60  80  80  80 F  60  80  80  80  20   0  20  20  40  60  60  60 G  60  80  80  80  20  20   0  20  60  80  80  80 H  60  80  80  80  20  20  20   0  60  80  80  80 I 100 120 120 120  60  40  60  60   0  20  20  20 J 120 140 140 140  80  60  80  80  20   0  20  20 K 120 140 140 140  80  60  80  80  20  20   0  20 L 120 140 140 140  80  60  80  80  20  20  20   0   Is there any method to extract clusters from M (if needed, the number of clusters can be fixed), such that each cluster contains nodes with small distances between them. In the example, the clusters would be (A, B, C, D), (E, F, G, H) and (I, J, K, L).  I've already tried UPGMA and k-means but the resulting clusters are very bad.  The distances are the average steps a random walker would take to go from node A to node B (!= A) and go back to node A. It's guaranteed that M^1/2 is a metric. To run k-means, I don't use the centroid. I define the distance between node n cluster c as the average distance between n and all nodes in c.  Thanks a lot :) For what values of $\alpha$, does this integral converge? For what values of $\alpha&gt;0$ this integral converges $$\int_0^{\infty} \frac {\sin x}{x^{\alpha}}dx $$ Tips for getting really good answers on SO The way the askers write questions is a factor in determining how good the answers we get are. Obviously, if you ask a clear, direct question it is easier for a someone to answer you.  But, sometimes I've done that and my questions have still been overlooked.  I've noticed some question-posting methods that aren't exactly obvious, but do help me get better answers.    Some tricks I've learned...   Even if my question is very complicated, I try to write a short question.  People get turned off by longer questions, probably because they think its not worth their time (relative to other questions with equal reputation potential).  After I get some traffic and votes on my question, and maybe some comments like "Can you post the code?" or "Clarify this..." I might post more, but by then I am already getting attention to my question.  So, in summary, even if I know the answer requires a long question, I don't make it long until I've already gotten people to look at it. I use more generic tags when possible.  People are more likely to have c# and linq as a favorite tag, than MethodCallExpression, and I tend to get more views if I use at least one or two general purpose tags along with my more specific tags. I've noticed that if I give my question the performance tag, then SO heavy-weights like Marc Gravell, Jon Skeet and Eric Lippert are more likely to answer my question (especially if I use it in conjunction with a C# tag).  Since having this realization, if I can think of a way to rephrase my question to sound like it is related to C# performance, I will word it as such and tag it accordingly.   "Be polite. SO Users HATE when people be impatient, rude or impolite." - Benny   So,  Does anyone else have any tips for getting better answers and question-recognition on SO?  I think it would be really helpful if everyone contributed their own observations and techniques here.  P.S. This question is probably too long. How can I find out what is using the hard disk? Possible Duplicates:             Once or twice a day my computer starts writing significantly hard to the hard drive, the HD led is ON and the performance hit is noticeable. A strange observation is that the Task Viewer does not show I/O activity - even Process Explorer shows no CPU activity and no I/O bytes read or written.  Is there a way to know which application is using the hard drive and how much data is it reading or writing? I'm trying to do something like the following:  enum E;  void Foo(E e);  enum E {A, B, C};   which the compiler rejects.  I've had a quick look on Google and the consensus seems to be "you can't do it", but I can't understand why.  Can anyone explain?  Clarification 2: I'm doing this as I have private methods in a class that take said enum, and I do not want the enum's values exposed - so, for example, I do not want anyone to know that E is defined as  enum E {     FUNCTIONALITY_NORMAL, FUNCTIONALITY_RESTRICTED, FUNCTIONALITY_FOR_PROJECT_X }   as project X is not something I want my users to know about.  So, I wanted to forward declare the enum so I could put the private methods in the header file, declare the enum internally in the cpp, and distribute the built library file and header to people.  As for the compiler - it's GCC.