numpy.promote_types

numpy.promote_types(type1, type2)

Returns the data type with the smallest size and smallest scalar kind to which both type1 and type2 may be safely cast. The returned data type is always in native byte order.

This function is symmetric and associative.

Parameters :

type1 : dtype or dtype specifier

First data type.

type2 : dtype or dtype specifier

Second data type.

Returns :

out : dtype

The promoted data type.

See also

result_type, dtype, can_cast

Notes

New in version 1.6.0.

Examples

>>> np.promote_types('f4', 'f8')
dtype('float64')

>>> np.promote_types('i8', 'f4')
dtype('float64')

>>> np.promote_types('>i8', '<c8')
dtype('complex128')

>>> np.promote_types('i1', 'S8')
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
TypeError: invalid type promotion