I'm having trouble setting up Kivy with Pygame on Mac OS X
pygame installation issue in mac os
How can I move files and view the progress (e.g. with a progress bar)? When moving large directories using mv, is there a way to view the progress (%)? The cp command on gentoo had a -g switch that showed the progress. The converse of Newton's shell theorem Encouraging people to explain downvotes Note: If you're looking for a simple explanation as to why comments aren't required on downvotes, see .   I used to get "upset" (though that is too strong a term) when I got downvoted without comment. If my answer isn't good enough then I'd like to know why. Not only does it improve the answer for the OP but it improves my knowledge too.  Where the down-vote has been explained I've found it useful &amp; it has improved my answer, or forced me to delete the answer if it was totally wrong.  So is there any way we can encourage people to leave a comment? Perhaps they don't lose rep if they explain their down-vote?  I must admit though that I haven't always explained my down-vote either so you could call me a hypocrite. I've also grown a thicker skin over the months of using SO (it seems to have come with the higher rep score ;-)), so I'm less bothered about this now. Continuous function positive at a point is positive in a neighborhood of that point Pretty much the problem asks if a function is continuous at the point $c$ and $f(c) &gt; 0$ then there exists a $d &gt; 0$ such that $\forall x$, $f(x) &gt; 0$ with $|x-c| &lt; d$.   I can understand what the problem means. That if a function is positive at a point then there is another point that's really close that'll also be positive. I can not prove this in a formal way though. I've tried using the intermediate value theorem and I do not know hot to implement it. Any ideas? Suppose I installed ubuntu with the user usr1 then I added usr2. I then create a group grp1 where this 2 users are added. A folder is owned by usr1 and has group grp1. But when I login as usr2 I cannot write. The folder has permissions 755...  usr2@kmserver:/media/data/www$ groups usr1 usr1 : grp1 ... usr2@kmserver:/media/data/www$ groups usr2 usr2 : grp1 ... usr2@kmserver:/media/data$ ls -l total 20 drwx------ 2 root root 16384 2011-05-12 10:53 lost+found drwxrwxr-x 2 grp1   grp1    4096 2011-05-12 15:15 www   Whats wrong? How can I determine whether a 2D Point is within a Polygon? The general consensus on a similar question,  is that "highly significant" is a valid, though non-specific, way to describe the strength of an association that has a p-value far below your pre-set significance threshold. However, what about describing p-values that are slightly above your threshold? I have seen some papers use terms like "somewhat significant", "nearly significant", "approaching significance", and so on. I find these terms to be a little wishy-washy, in some cases a borderline disingenuous way to pull a meaningful result out of a study with negative results. Are these terms acceptable to describe results that "just miss" your p-value cutoff? Sum of a Hyper-geometric series. (NBHM 2011) How to find the sum of the following series $$\frac{1}{5} - \frac{1\cdot 4}{5\cdot 10} + \frac{1\cdot 4\cdot 7}{5\cdot 10\cdot 15} - \dots\,.?$$  I have no idea. I have written the general term and tested its convergence by Gauss' test for convergence, but they are neither the question nor the answer. "They are quite full up this year." After these instructions in the Python interpreter one gets a window with a plot:  from matplotlib.pyplot import * plot([1,2,3]) show() # other code   Unfortunately, I don't know how to continue to interactively explore the figure created by show() while the program does further calculations.  Is it possible at all? Sometimes calculations are long and it would help if they would proceed during examination of intermediate results. In python, if I say  print 'h'   I get the letter h and a newline.  If I say   print 'h',   I get the letter h and no newline.  If I say  print 'h', print 'm',   I get the letter h, a space, and the letter m.  How can I prevent Python from printing the space?  The print statements are different iterations of the same loop so I can't just use the + operator. I'm having some trouble understanding a proof on  on Number Theory and I was wondering if you guys could give me some help. The problem is that I don't understand the last implication on the proof for example 1.1     Example 1.1. Let x and y be integers. Prove that 2x + 3y is divisible by 17 iff 9x + 5y is divisible by 17.      Solution. 17 | (2x + 3y) ⇒ 17 | [13(2x + 3y)], or 17 | (26x + 39y) ⇒ 17 | (9x + 5y)       conversely, 17 | (9x + 5y) ⇒ 17 | [4(9x + 5y)], or 17 | (36x + 20y) ⇒ 17 | (2x + 3y).   My problem is that I don't understand how does 17 | (26x + 39y) imply 17 | (9x + 5y). If you could elaborate on this step I would be most grateful.  I'm sorry if this is an obvious question but I am a beginner and I just can't get it.  Thanks for your help in advance. SVN repository backup strategies I'm new to SVN and I'd like to know what methods are available for backing up repositories in a Windows environment? Shell with better editing capabilities Shells (at least what I know) have really bad command editing capabilities.  For example:    I can't point the cursor to any point of the command. I can't select and backspace/delete/replace text in the command.   Currently these are so distracting, I use gedit to edit commands before pasting them to the terminal.  Is there any solution that's good for these? The minimum system requirements for 18.04 are "2 GHz dual core processor or better"; would a quad-core at 1.8 GHz meet (or approximate) this requirement? How many Naruto Shippuden dubbed episodes are there? I am watching Naruto and I am currently on episode 164. How many episodes of Shippuden do they have dubbed, and are they still dubbing it? What is the relationship between a chi squared test and test of equal proportions? Suppose that I have three populations with four, mutually exclusive characteristics.  I take random samples from each population and construct a crosstab or frequency table for the characteristics that I am measuring.  Am I correct in saying that:   If I wanted to test whether there is any relationship between the populations and the characteristics (e.g. whether one population has a higher frequency of one of the characteristics), I should run a chi-squared test and see whether the result is significant. If the chi-squared test is significant, it only shows me that there is some relationship between the populations and characteristics, but not how they are related. Furthermore, not all of the characteristics need to be related to the population.  For example, if the different populations have significantly different distributions of characteristics A and B, but not of C and D, then the chi-squared test may still come back as significant. If I wanted to measure whether or not a specific characteristic is affected by the population, then I can run a test for equal proportions (I have seen this called a z-test, or as prop.test() in R) on just that characteristic.   In other words, is it appropriate to use the prop.test() to more accurately determine the nature of a relationship between two sets of categories when the chi-squared test says that there is a significant relationship? The advantages and disadvantages of using Kaiser Rule to select the number of principal components Is the Kaiser rule (choosing only PCs with eigenvalues >1, ) a reasonable method to select the number of principal components to retain? What are its pros and cons? Poll in background for StackExchange™ MultiCollider SuperDropdown™ inbox events and update the titlebar accordingly à la Facebook Sometimes when reading through user comments on a particular answer, some usernames that appear like user[digit] e.g user12345 are not links. Is this a known behaviour or any other thing I am not aware of?