import numpy
from cupy import core
[docs]def copyto(dst, src, casting='same_kind', where=None):
"""Copies values from one array to another with broadcasting.
This function can be called for arrays on different devices. In this case,
casting, ``where``, and broadcasting is not supported, and an exception is
raised if these are used.
Args:
dst (cupy.ndarray): Target array.
src (cupy.ndarray): Source array.
casting (str): Casting rule. See :func:`numpy.can_cast` for detail.
where (cupy.ndarray of bool): If specified, this array acts as a mask,
and an element is copied only if the corresponding element of
``where`` is True.
.. seealso:: :func:`numpy.copyto`
"""
if not numpy.can_cast(src.dtype, dst.dtype, casting):
raise TypeError('Cannot cast %s to %s in %s casting mode' %
(src.dtype, dst.dtype, casting))
if dst.size == 0:
return
if where is None:
if _can_memcpy(dst, src):
dst.data.copy_from(src.data, src.nbytes)
else:
core.elementwise_copy(src, dst)
else:
core.elementwise_copy_where(src, where, dst)
def _can_memcpy(dst, src):
c_contiguous = dst.flags.c_contiguous and src.flags.c_contiguous
f_contiguous = dst.flags.f_contiguous and src.flags.f_contiguous
return (c_contiguous or f_contiguous) and dst.dtype == src.dtype and \
dst.size == src.size