NumPy Data type: can_cast() function

Last update on August 19 2022 21:50:38 (UTC/GMT +8 hours)

numpy.can_cast() function

The can_cast() function returns True if cast between data types can occur according to the casting rule. If from is a scalar or array scalar, also returns True if the scalar value can be cast without overflow or truncation to an integer.

Version: 1.15.0

Syntax:

numpy.can_cast(from_, to, casting='safe')

Parameter:

Name	Description	Required / Optional
from_	Data type, scalar, or array to cast from.	Required
to	Data type to cast to.	Required
casting	Controls what kind of data casting may occur. 'no' means the data types should not be cast at all. 'equiv' means only byte-order changes are allowed. 'safe' means only casts which can preserve values are allowed. 'same_kind' means only safe casts or casts within a kind, like float64 to float32, are allowed. 'unsafe' means any data conversions may be done.	Optional

Return value:

out : bool - True if cast can occur according to the casting rule.

Example-1: numpy.can_cast() function


>>> np.can_cast(np.int32, np.int64)
True
>>> np.can_cast(np.float64, complex)
True
>>> np.can_cast(complex, float)
False
>>>
>>> np.can_cast('i8', 'f8')
True
>>> np.can_cast('i8', 'f4')
False
>>> np.can_cast('i4', 'S4')
False

Pictorial Presentation:

Pictorial Presentation:

Example-2: numpy.can_cast() function


>>> np.can_cast(100, 'i1')
True
>>> np.can_cast(150, 'i1')
False
>>> np.can_cast(150, 'u1')
True
>>>
>>> np.can_cast(3.5e100, np.float32)
False
>>> np.can_cast(1000.0, np.float32)
True

Example-3: numpy.can_cast() function


>>> np.can_cast(np.array(1000.0), np.float32)
True
>>> np.can_cast(np.array([1000.0]), np.float32)
False

Example-4: numpy.can_cast() function

>>> import numpy as np
>>> np.can_cast('i8', 'i8', 'no')
True
>>> np.can_cast('<i8', '>i8', 'no')
False
>>>
>>> np.can_cast('<i8', '>i8', 'equiv')
True
>>> np.can_cast('<i4', '>i8', 'equiv')
False
>>>
>>> np.can_cast('<i4', '>i8', 'safe')
True
>>> np.can_cast('<i8', '>i4', 'safe')
False
>>>
>>> np.can_cast('<i8', '>i4', 'same_kind')
True
>>> np.can_cast('<i8', '>u4', 'same_kind')
False
>>>
>>> np.can_cast('<i8', '>u4', 'unsafe')
True

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