from chainer import cuda
from chainer import function
from chainer import utils
from chainer.utils import type_check
class Ceil(function.Function):
@property
def label(self):
return 'ceil'
def check_type_forward(self, in_types):
type_check.expect(
in_types.size() == 1,
in_types[0].dtype.kind == 'f',
)
def forward(self, x):
xp = cuda.get_array_module(*x)
return utils.force_array(xp.ceil(x[0]), x[0].dtype),
def backward(self, x, grad_outputs):
xp = cuda.get_array_module(*x)
return xp.zeros_like(x[0]),
[docs]def ceil(x):
"""Elementwise ceil function.
.. math::
y_i = \\lceil x_i \\rceil
Args:
x (~chainer.Variable): Input variable.
Returns:
~chainer.Variable: Output variable.
"""
return Ceil()(x)