title: Why am I getting the return value of None and what does it mean?
body: <p>I do no understand very well, the result: "none".  I am trying to start elimination (Gauss) code, but I receive the result: "None".</p>
  
  <pre><code>from numpy import *
  a= array([[1,0],[0,2]])
  b= array([1,4])
  
  def gauss(a,b):
      n=len(b)
  
      k=0
      while k in range (0, n-1):
          i=k+1
          while i in range ((k+1),(n)):
              a[i,k]=a[i,k]/a[k,k]
              j=k+1
              while j in range ((k+1),(n)):
                  a[i,j]=a[i,j]-a[i,k]*a[i,k]
                  j=j+1
              b[i]=b[i]-a[i,k]*b[k]
              i=i+1
          k=k+1
          return a
          return b
  
   print gauss(a,b)
  </code></pre>