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# numpy.unravel_index

`numpy.``unravel_index`(x, dims)

  Convert a flat index to an index tuple for an array of given shape.

  Parameters : | x : int Flattened index. dims : tuple of ints Input shape, the shape of an array into which indexing is required.
  Returns : | idx : tuple of ints Tuple of the same shape as dims, containing the unraveled index.

  Notes

  In the Examples section, since `arr.flat[x] == arr.max()` it may be easier to use flattened indexing than to re-map the index to a tuple.

  Examples

      >>> arr = np.arange(20).reshape(5, 4)
      >>> arr
      array([[ 0,  1,  2,  3],
             [ 4,  5,  6,  7],
             [ 8,  9, 10, 11],
             [12, 13, 14, 15],
             [16, 17, 18, 19]])
      >>> x = arr.argmax()
      >>> x
      19
      >>> dims = arr.shape
      >>> idx = np.unravel_index(x, dims)
      >>> idx
      (4, 3)
      >>> arr[idx] == arr.max()
      True

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