title: How do I pass a filename from the command line and use it in genfromtxt?
body: <p>I need to explain more clearly because from the title you can't completely  comprehend my needs... </p>
  
  <pre><code>    File = input ("Insert the name of the file: ")
  
      IV = np.genfromtxt('D:\User\Python\Programms_Python\programms\%d.txt', 
      File, usecols=(1,5,2,5))
  </code></pre>
  
  <p>I need to insert from command line the name of the file I want to analyze, because I have to do multiple analyses on many different <code>.txt</code> files and inserting their names directly from the command line would make my job much faster. Can you suggest a way to insert it inside the function <code>genfromtxt</code>? Is it possible? </p>
  
  <p>genfromtxt is a function inside numpy and it allows you to copy the values of a column in your txt inside an array, using usecols you can ask which column to copy in the array which this way can become a multidimensional array, like in this case IV is a four dimensional array.</p>
  
  <p>Trying the way I showed above, <code>genfromtxt</code> doesn't recognize the <code>%d -&gt; File</code> (the names of the <code>.txt</code> files are just numbers and I tried also with <code>%s</code> but it didn't change) so please.. HELP </p>