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# numpy.putmask

`numpy.``putmask`(a, mask, values)

  Changes elements of an array based on conditional and input values.

  Sets a.flat[n] = values[n] for each n where mask.flat[n] is true.

  If values is not the same size as a and mask then it will repeat. This gives behavior different from a[mask] = values.

  Parameters: | a : array_like Array to put data into mask : array_like Boolean mask array values : array_like Values to put

  See also

  `place`, `put`, `take`

  Examples

      >>> a = np.array([10,20,30,40])
      >>> mask = np.array([True,False,True,True])
      >>> a.putmask([60,70,80,90], mask)
      >>> a
      array([60, 20, 80, 90])
      >>> a = np.array([10,20,30,40])
      >>> a[mask]
      array([60, 80, 90])
      >>> a[mask] = np.array([60,70,80,90])
      >>> a
      array([60, 20, 70, 80])
      >>> a.putmask([10,90], mask)
      >>> a
      array([10, 20, 10, 90])
      >>> np.putmask(a, mask, [60,70,80,90])

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