Compute bit-wise inversion, or bit-wise NOT, element-wise.
Computes the bit-wise NOT of the underlying binary representation of
the integers in the input arrays. This ufunc implements the C/Python
operator ~.
For signed integer inputs, the two’s complement is returned.
In a two’s-complement system negative numbers are represented by the two’s
complement of the absolute value. This is the most common method of
representing signed integers on computers [R31]. A N-bit two’s-complement
system can represent every integer in the range
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| Parameters : | x1 : array_like
Only integer types are handled (including booleans).
|
|---|
| Returns : | out : array_like
|
|---|
Notes
bitwise_not is an alias for invert:
>>> np.bitwise_not is np.invert
True
References
Examples
We’ve seen that 13 is represented by 00001101.
The invert or bit-wise NOT of 13 is then:
>>> np.invert(np.array([13], dtype=uint8))
array([242], dtype=uint8)
>>> np.binary_repr(x, width=8)
'00001101'
>>> np.binary_repr(242, width=8)
'11110010'
The result depends on the bit-width:
>>> np.invert(np.array([13], dtype=uint16))
array([65522], dtype=uint16)
>>> np.binary_repr(x, width=16)
'0000000000001101'
>>> np.binary_repr(65522, width=16)
'1111111111110010'
When using signed integer types the result is the two’s complement of
the result for the unsigned type:
>>> np.invert(np.array([13], dtype=int8))
array([-14], dtype=int8)
>>> np.binary_repr(-14, width=8)
'11110010'
Booleans are accepted as well:
>>> np.invert(array([True, False]))
array([False, True], dtype=bool)
