I have a list in list. All the values are False. I have to change value to True of a very specific one.  s=[[False,False,False,False]    [False,False,False,False]    [False,False,False,False]    [False,False,False,False]]   I want to change it into this:  s=[[False,False,False,False]    [False,False,False,False]    [False,True,False,False]    [False,False,False,False]]   P.s.: I tried doing this:  s[2][1]=True   But i got this:  [[False,True,False,False] [False,True,False,False] [False,True,False,False] [False,True,False,False]]
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?
I know there are some command-line applications like pdflatex that can help me to compile a LaTex document from C#.Net (using the System.Diagnostics.Process class) .   I wanna know that what's the best command-line tool for compiling a TeX document ? How do I simulate flip of biased coin? In unbiased coin flip H or T occurs 50% of times.  But I want to simulate coin which gives H  with probability 'p' and T with probability '(1-p)'.  something like this:  def flip(p):    '''this function return H with probability p'''    # do something    return result  &gt;&gt; [flip(0.8) for i in xrange(10)] [H,H,T,H,H,H,T,H,H,H] Can we get a better wording for protected questions? For context, see .  In essence:     "This question is protected to prevent "thanks!", "me too!", or spam answers by new users. To answer it, you must have earned at least 10 reputation (not including the ) on this site."   Suggested addition to existing message is in bold. Why Do Glueballs Have Mass, When Individual Gluons Are Massless? Opening PDF in Illustrator breaks up text objects I recently had to convert some PDF files to SVG, and did this by opening the PDF in Illustrator, and saving out to SVG.    The issue was that when Illustrator opened the pdf, many (but not all) text objects would be broken up into different text objects.  For instance, the word "policy" wouldn't be one text object, but rather several text objects, "po", "l", "icy".  There didn't seem to be any rhyme or reason to it.    How can I prevent this from happening? No hair theorem for black holes and the baryon number GCSE: Find the number of person that will go to a party Remove space around tikz how I can draw an skew cylinder (rotate around x axis) and fill it (in 3D tikz)? I know in php you are able to make a call like:  $function_name = 'hello'; $function_name();  function hello() { echo 'hello'; }   Is this possible in .Net? Pure virtual destructor in C++ how to display the actual network traffic (wireless) in a terminal?  Additionally: Is it possible to add this info to the chart of top? How to compare two Pearson correlation coefficients Since a few days I do not get ahead when trying to compare two Pearson correlation coefficients. Imagine that I've got two datasets where on each I do a correlation between Land Surface Temperature and an urban metric. The datasets are different in their length, so the first one has round about 160.000 observables and the second one has about 2400 observables. For the correlation on the first dataset I get a Pearson of -0.74 and for the second I get -0.885. Now I want to find out whether these coefficients are significantly different from each other. Is there any appropriate method you could suggest?  I already played around with the Fisher-Z-Transformation, but from my point of view with no purposeful results. 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For the BeginDate, we want it to be dependent on transaction date and not the current getdate time. We are reprocessing a history of transactions. Example below, customer has gym or bank status, and goes from inactive, to active, or pending, dependent on transaction date.  We currently have this.  CREATE TABLE dbo.Department (     CustomerId int primary key,     MembershipStatus int,     TransactionDate datetime  );   We we would like to create a table like this.  CREATE TABLE dbo.DepartmentHistory (     CustomerId int primary key,     MembershipStatus int,     TransactionDate datetime,     BeginDatetime datetime,     EndDatettime datetime  );   Example usage would be:   first Customer Transaction on 3/5/2018 as Pending P        +------------+--------+-----------+---------+     | CustomerId | Status | BeginDate | EndDate |     +------------+--------+-----------+---------+     | 1          | P      | 3/5/2018  | NULL    |     +------------+--------+-----------+---------+    second transaction is 4/21/2018 is Active A        +------------+--------+-----------+-----------+     | CustomerId | Status | BeginDate | EndDate   |     +------------+--------+-----------+-----------+     | 1          | P      | 3/5/2018  | 4/21/2018 |     | 1          | A      | 4/21/2018 | NULL      |     +------------+--------+-----------+-----------+ Normally Star Trek seems to based on some sort of logic, but the time travel in "Star Trek: Enterprise" seems to have no logic at all, or  am I just missing it?  Example: If they go back in time to change something it takes time until it has any effect in the future? I can't see any reason for this. How to download a file over HTTP? I have a small utility that I use to download an MP3 file from a website on a schedule and then builds/updates a podcast XML file which I've added to iTunes.  The text processing that creates/updates the XML file is written in Python. However, I use wget inside a Windows .bat file to download the actual MP3 file. I would prefer to have the entire utility written in Python.  I struggled to find a way to actually download the file in Python, thus why I resorted to using wget.  So, how do I download the file using Python? How to remove the whitespace BEFORE itemize/enumerate? I'm somewhat of a LaTeX noob, and this is driving me completely nuts.  When I type  \documentclass{article} \usepackage{enumitem}  \begin{document}     Some text     \begin{itemize}[noitemsep]         \item Item 1         \item Item 2         \item Item 3     \end{itemize} \end{document}   I don't want the space which appears in between the text "Some text" and the itemization to be there:    When I search around on Google all I see is tons of long, complicated advice on this site, StackOverflow, forums, etc. on how to not fix the problem ("parskip is evil", etc.), or tons of vague/confusing answers on what package to look at, with no actual example for me to learn from.  So while this question is already asked many times, I have never found a single concrete answer to this question.    The question couldn't be simpler: How do I "properly" get rid of this extra space? One way function existence Let $x = (x_1, x_2,...,x_n)\in\{0,1\}^n$ for $n\in\mathbb{N}$. Prove that if one-way functions (OWFs) exist, then there exists a one-way function $f$ such that for every bit $i\in[1,n]$ there exists an algorithm $A_i$ such that: $$\Pr[A_i(f(x)) = x_i] \geq \frac{1}{2} + \frac{1}{2n}$$ I'm having trouble understanding this.