/
exponential_m1.py
41 lines (29 loc) · 983 Bytes
/
exponential_m1.py
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
import numpy
from chainer.backends import cuda
from chainer import function_node
from chainer import utils
from chainer.utils import type_check
class Expm1(function_node.FunctionNode):
@property
def label(self):
return 'expm1'
def check_type_forward(self, in_types):
type_check._argname(in_types, ('x',))
type_check.expect(in_types[0].dtype.kind == 'f')
def forward_cpu(self, x):
self.retain_outputs((0,))
return utils.force_array(numpy.expm1(x[0])),
def forward_gpu(self, x):
self.retain_outputs((0,))
return cuda.cupy.expm1(x[0]),
def backward(self, indexes, gy):
y = self.get_retained_outputs()[0]
return (y + 1.0) * gy[0],
def expm1(x):
"""Elementwise exponential minus one function.
Args:
x (:class:`~chainer.Variable` or :ref:`ndarray`): Input variable.
Returns:
~chainer.Variable: Output variable.
"""
return Expm1().apply((x,))[0]