com.intel.analytics.bigdl.nn.AddConstant.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

import com.intel.analytics.bigdl.nn.abstractnn.TensorModule
import com.intel.analytics.bigdl.tensor.Tensor
import com.intel.analytics.bigdl.tensor.TensorNumericMath.TensorNumeric

import scala.reflect.ClassTag

/**
 *  adding a constant
 *
 * @param constant_scalar constant value
 * @param inplace Can optionally do its operation in-place without using extra state memory
 */
@SerialVersionUID(- 1572711921601326233L)
class AddConstant[T: ClassTag](
   val constant_scalar: Double,
   val inplace: Boolean = false
  )(implicit ev: TensorNumeric[T]) extends TensorModule[T] {
  val scalar = ev.fromType[Double](constant_scalar)

  override def updateOutput(input: Tensor[T]): Tensor[T] = {
    if (inplace) {
      input.add(scalar)
      output.set(input)
    } else {
      output.resizeAs(input).copy(input)
      output.add(scalar)
    }
    output
  }

  override def updateGradInput(input: Tensor[T], gradOutput: Tensor[T]): Tensor[T] = {
    if (inplace) {
      gradInput.set(gradOutput)
      input.add(ev.negative(scalar))
    } else {
      gradInput.resizeAs(input).copy(gradOutput)
    }
    gradInput
  }

  override def toString(): String = {
    s"${getPrintName}($constant_scalar, $inplace)"
  }

  override def canEqual(other: Any): Boolean = other.isInstanceOf[AddConstant[T]]

  override def equals(other: Any): Boolean = other match {
    case that: AddConstant[T] =>
      super.equals(that) &&
        (that canEqual this) &&
        constant_scalar == that.constant_scalar &&
        inplace == that.inplace
    case _ => false
  }

  override def hashCode(): Int = {
    def getHashCode(a: Any): Int = if (a == null) 0 else a.hashCode()
    val state = Seq(super.hashCode(), constant_scalar, inplace)
    state.map(getHashCode).foldLeft(0)((a, b) => 31 * a + b)
  }

  override def clearState(): this.type = {
    if (!inplace) {
      super.clearState()
    }
    this
  }
}

object AddConstant {
  def apply[@specialized(Float, Double) T: ClassTag](
    constant_scalar: Double,
    inplace: Boolean = false)(implicit ev: TensorNumeric[T]) : AddConstant[T] = {
    new AddConstant[T](constant_scalar, inplace)
  }
}