com.intel.analytics.bigdl.nn.keras.Activation.scala Maven / Gradle / Ivy
/*
* Copyright 2016 The BigDL Authors.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package com.intel.analytics.bigdl.nn.keras
import com.intel.analytics.bigdl.nn.abstractnn.{AbstractModule, IdentityOutputShape}
import com.intel.analytics.bigdl.tensor.Tensor
import com.intel.analytics.bigdl.tensor.TensorNumericMath.TensorNumeric
import com.intel.analytics.bigdl.utils.Shape
import scala.reflect.ClassTag
/**
* Simple activation function to be applied to the output.
* Available activations: 'tanh', 'relu', 'sigmoid', 'softmax', 'softplus',
* 'softsign', 'hard_sigmoid'.
*
* When you use this layer as the first layer of a model, you need to provide the argument
* inputShape (a Single Shape, does not include the batch dimension).
*
* @param activation Name of the activation function as string.
* @tparam T Numeric type of parameter(e.g. weight, bias). Only support float/double now.
*/
class Activation[T: ClassTag](
val activation: String,
val inputShape: Shape = null)(implicit ev: TensorNumeric[T])
extends KerasLayer[Tensor[T], Tensor[T], T](KerasLayer.addBatch(inputShape))
with IdentityOutputShape {
require(activation != null, "The name of an activation function as a string is required")
override def doBuild(inputShape: Shape): AbstractModule[Tensor[T], Tensor[T], T] = {
val kerasActivation = KerasUtils.getKerasActivation(activation)
kerasActivation.doBuild(inputShape)
}
}
object Activation {
def apply[@specialized(Float, Double) T: ClassTag](
activation: String,
inputShape: Shape = null)(implicit ev: TensorNumeric[T]): Activation[T] = {
new Activation[T](activation, inputShape)
}
}