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# numpy.diff

`numpy.``diff`(a, n=1, axis=-1)

  Calculate the nth order discrete difference along given axis.

  Parameters: | a : array_like Input array n : int, optional The number of times values are differenced. axis : int, optional The axis along which the difference is taken.
  Returns: | out : ndarray The n order differences. The shape of the output is the same as a except along axis where the dimension is n less.

  Examples

      >>> x = np.array([0,1,3,9,5,10])
      >>> np.diff(x)
      array([ 1,  2,  6, -4,  5])
      >>> np.diff(x,n=2)
      array([  1,   4, -10,   9])
      >>> x = np.array([[1,3,6,10],[0,5,6,8]])
      >>> np.diff(x)
      array([[2, 3, 4],
      [5, 1, 2]])
      >>> np.diff(x,axis=0)
      array([[-1,  2,  0, -2]])

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