title: How to fill 2d-array with increasing numbers?
body: <p>I want to create an array with numbers going from 0 to 10 in its 1st sub-array, from 11 to 20 in its 2nd and so on...</p>
  
  <p>I can create the sub arrays with </p>
  
  <pre><code>for i in range(10):
      print np.arange(10*i, 10*(i+1))
  </code></pre>
  
  <p>which gives me </p>
  
  <pre><code>[0 1 2 3 4 5 6 7 8 9]
  [10 11 12 13 14 15 16 17 18 19]
  [20 21 22 23 24 25 26 27 28 29]
  [30 31 32 33 34 35 36 37 38 39]
  [40 41 42 43 44 45 46 47 48 49]
  [50 51 52 53 54 55 56 57 58 59]
  [60 61 62 63 64 65 66 67 68 69]
  [70 71 72 73 74 75 76 77 78 79]
  [80 81 82 83 84 85 86 87 88 89]
  [90 91 92 93 94 95 96 97 98 99]
  </code></pre>
  
  <p>but I can't fit it inside an array...
  Tried - </p>
  
  <pre><code>a = np.array((10,10))
  for i in range(10):
      a[i] = np.arange(10*i, 10*(i+1))
  </code></pre>
  
  <p>Which gave <code>ValueError: setting an array element with a sequence.</code> How can I fix this?</p>
  
  <p><strong>Edit:</strong></p>
  
  <p>All the answers here provide a working way to achieve what I want, which is the main thing I wanted, but I also want to understand why the error appears, since the <code>np.arange()</code>, from what I understand, returns an ndarray</p>