Convert ndarray from float64 to integer

>>> a = numpy.array([1, 2, 3, 4], dtype=numpy.float64)
>>> a
array([ 1.,  2.,  3.,  4.])
>>> a.astype(numpy.int64)
array([1, 2, 3, 4])

In [10]: numeric_strings = np.array(['1.25','-9.6','42'])

In [11]: numeric_strings
Out[11]:
array(['1.25', '-9.6', '42'],
      dtype='|S4')

In [13]: numeric_strings.astype(float32)
Out[13]: array([  1.25      ,  -9.60000038,  42.        ], dtype=float32)