Coverage for /pythoncovmergedfiles/medio/medio/usr/local/lib/python3.8/site-packages/keras/src/layers/merging/subtract.py: 61%

1# Copyright 2015 The TensorFlow Authors. All Rights Reserved. 

2# 

3# Licensed under the Apache License, Version 2.0 (the "License"); 

4# you may not use this file except in compliance with the License. 

5# You may obtain a copy of the License at 

6# 

7# http://www.apache.org/licenses/LICENSE-2.0 

8# 

9# Unless required by applicable law or agreed to in writing, software 

10# distributed under the License is distributed on an "AS IS" BASIS, 

11# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 

12# See the License for the specific language governing permissions and 

13# limitations under the License. 

14# ============================================================================== 

15"""Layer that subtracts two inputs.""" 

16 

17 

18from keras.src.layers.merging.base_merge import _Merge 

19from keras.src.utils import tf_utils 

20 

21# isort: off 

22from tensorflow.python.util.tf_export import keras_export 

23 

24 

25@keras_export("keras.layers.Subtract") 

26class Subtract(_Merge): 

27 """Layer that subtracts two inputs. 

28 

29 It takes as input a list of tensors of size 2, both of the same shape, and 

30 returns a single tensor, (inputs[0] - inputs[1]), also of the same shape. 

31 

32 Examples: 

33 

34 ```python 

35 import keras.src as keras 

36 

37 input1 = keras.layers.Input(shape=(16,)) 

38 x1 = keras.layers.Dense(8, activation='relu')(input1) 

39 input2 = keras.layers.Input(shape=(32,)) 

40 x2 = keras.layers.Dense(8, activation='relu')(input2) 

41 # Equivalent to subtracted = keras.layers.subtract([x1, x2]) 

42 subtracted = keras.layers.Subtract()([x1, x2]) 

43 

44 out = keras.layers.Dense(4)(subtracted) 

45 model = keras.models.Model(inputs=[input1, input2], outputs=out) 

46 ``` 

47 """ 

48 

49 @tf_utils.shape_type_conversion 

50 def build(self, input_shape): 

51 super().build(input_shape) 

52 if len(input_shape) != 2: 

53 raise ValueError( 

54 "A `Subtract` layer should be called on exactly 2 inputs. " 

55 f"Received: input_shape={input_shape}" 

56 ) 

57 

58 def _merge_function(self, inputs): 

59 if len(inputs) != 2: 

60 raise ValueError( 

61 "A `Subtract` layer should be called on exactly 2 inputs. " 

62 f"Received: inputs={inputs}" 

63 ) 

64 return inputs[0] - inputs[1] 

65 

66 

67@keras_export("keras.layers.subtract") 

68def subtract(inputs, **kwargs): 

69 """Functional interface to the `Subtract` layer. 

70 

71 Args: 

72 inputs: A list of input tensors (exactly 2). 

73 **kwargs: Standard layer keyword arguments. 

74 

75 Returns: 

76 A tensor, the difference of the inputs. 

77 

78 Examples: 

79 

80 ```python 

81 import keras.src as keras 

82 

83 input1 = keras.layers.Input(shape=(16,)) 

84 x1 = keras.layers.Dense(8, activation='relu')(input1) 

85 input2 = keras.layers.Input(shape=(32,)) 

86 x2 = keras.layers.Dense(8, activation='relu')(input2) 

87 subtracted = keras.layers.subtract([x1, x2]) 

88 

89 out = keras.layers.Dense(4)(subtracted) 

90 model = keras.models.Model(inputs=[input1, input2], outputs=out) 

91 ``` 

92 """ 

93 return Subtract(**kwargs)(inputs) 

94