1# -*- encoding: utf-8 -*- 

2# pylint: disable=E0203,E1101,C0111 

3""" 

4@file 

5@brief Runtime operator. 

6""" 

7import numpy 

8from ._op import OpRunUnaryNum 

9 

10 

11class Softmax(OpRunUnaryNum): 

12 

13 atts = {'axis': 1} 

14 

15 def __init__(self, onnx_node, desc=None, **options): 

16 OpRunUnaryNum.__init__(self, onnx_node, desc=desc, 

17 expected_attributes=Softmax.atts, 

18 **options) 

19 

20 def _run(self, X): # pylint: disable=W0221 

21 if self.inplaces.get(0, False): 

22 return self._run_inplace(X) 

23 tmp = X - X.max(axis=self.axis)[:, numpy.newaxis] 

24 Y = numpy.exp(tmp) 

25 Y /= Y.sum(axis=self.axis)[:, numpy.newaxis] 

26 return (Y, ) 

27 

28 def _run_inplace(self, X): 

29 X -= X.max(axis=self.axis)[:, numpy.newaxis] 

30 numpy.exp(X, out=X) 

31 X /= X.sum(axis=self.axis)[:, numpy.newaxis] 

32 return (X, ) 

33 

34 def to_python(self, inputs): 

35 lines = ["tmp = {0} - {0}.max(axis=axis)[:, numpy.newaxis]".format( 

36 inputs[0]), 

37 "Y = numpy.exp(tmp)", 

38 "Y /= Y.sum(axis=axis)[:, numpy.newaxis]", 

39 "return Y"] 

40 return ("import numpy", "\n".join(lines))