title: Numpy Python: How to change 2d array elements based on condition?
body: <p>I have a numpy 2D array representing some x,y coordinates.
  Given a reference point [a,b] and a distance 'c', I want to replace the elements in my 2D array, such that all points whose distance from [a,b]>c are set to [0,0] and those with a distance smaller than c are set to [1,1]. I tried to use where() in many variations, but did not succeed. </p>
  
  <p>Example Input: </p>
  
  <pre><code>arr2D = np.array([[10,20],[30,40],[50,60]])
  refPoint = np.array([29,41])
  c = 5
  </code></pre>
  
  <p>Output should be: <code>[[0,0],[1,1],[0,0]]</code></p>
  
  <p>Any help is appreciated...</p>