82 lines
3.1 KiB
Markdown
82 lines
3.1 KiB
Markdown
|
---
|
||
|
title: Multilayer Network
|
||
|
short_title: Multilayer Network
|
||
|
description: Simple and sequential network configuration.
|
||
|
category: Models
|
||
|
weight: 3
|
||
|
---
|
||
|
|
||
|
## Why use MultiLayerNetwork?
|
||
|
|
||
|
The `MultiLayerNetwork` class is the simplest network configuration API available in Eclipse Deeplearning4j. This class is useful for beginners or users who do not need a complex and branched network graph.
|
||
|
|
||
|
You will not want to use `MultiLayerNetwork` configuration if you are creating complex loss functions, using graph vertices, or doing advanced training such as a triplet network. This includes popular complex networks such as InceptionV4.
|
||
|
|
||
|
## Usage
|
||
|
|
||
|
The example below shows how to build a simple linear classifier using `DenseLayer` (a basic multiperceptron layer).
|
||
|
|
||
|
```java
|
||
|
MultiLayerConfiguration conf = new NeuralNetConfiguration.Builder()
|
||
|
.seed(seed)
|
||
|
.optimizationAlgo(OptimizationAlgorithm.STOCHASTIC_GRADIENT_DESCENT)
|
||
|
.learningRate(learningRate)
|
||
|
.updater(Updater.NESTEROVS).momentum(0.9)
|
||
|
.list()
|
||
|
.layer(0, new DenseLayer.Builder().nIn(numInputs).nOut(numHiddenNodes)
|
||
|
.weightInit(WeightInit.XAVIER)
|
||
|
.activation("relu")
|
||
|
.build())
|
||
|
.layer(1, new OutputLayer.Builder(LossFunction.NEGATIVELOGLIKELIHOOD)
|
||
|
.weightInit(WeightInit.XAVIER)
|
||
|
.activation("softmax").weightInit(WeightInit.XAVIER)
|
||
|
.nIn(numHiddenNodes).nOut(numOutputs).build())
|
||
|
.pretrain(false).backprop(true).build();
|
||
|
```
|
||
|
|
||
|
You can also create convolutional configurations:
|
||
|
|
||
|
```java
|
||
|
MultiLayerConfiguration.Builder builder = new NeuralNetConfiguration.Builder()
|
||
|
.seed(seed)
|
||
|
.regularization(true).l2(0.0005)
|
||
|
.learningRate(0.01)//.biasLearningRate(0.02)
|
||
|
//.learningRateDecayPolicy(LearningRatePolicy.Inverse).lrPolicyDecayRate(0.001).lrPolicyPower(0.75)
|
||
|
.weightInit(WeightInit.XAVIER)
|
||
|
.optimizationAlgo(OptimizationAlgorithm.STOCHASTIC_GRADIENT_DESCENT)
|
||
|
.updater(Updater.NESTEROVS).momentum(0.9)
|
||
|
.list()
|
||
|
.layer(0, new ConvolutionLayer.Builder(5, 5)
|
||
|
//nIn and nOut specify depth. nIn here is the nChannels and nOut is the number of filters to be applied
|
||
|
.nIn(nChannels)
|
||
|
.stride(1, 1)
|
||
|
.nOut(20)
|
||
|
.activation("identity")
|
||
|
.build())
|
||
|
.layer(1, new SubsamplingLayer.Builder(SubsamplingLayer.PoolingType.MAX)
|
||
|
.kernelSize(2,2)
|
||
|
.stride(2,2)
|
||
|
.build())
|
||
|
.layer(2, new ConvolutionLayer.Builder(5, 5)
|
||
|
//Note that nIn need not be specified in later layers
|
||
|
.stride(1, 1)
|
||
|
.nOut(50)
|
||
|
.activation("identity")
|
||
|
.build())
|
||
|
.layer(3, new SubsamplingLayer.Builder(SubsamplingLayer.PoolingType.MAX)
|
||
|
.kernelSize(2,2)
|
||
|
.stride(2,2)
|
||
|
.build())
|
||
|
.layer(4, new DenseLayer.Builder().activation("relu")
|
||
|
.nOut(500).build())
|
||
|
.layer(5, new OutputLayer.Builder(LossFunctions.LossFunction.NEGATIVELOGLIKELIHOOD)
|
||
|
.nOut(outputNum)
|
||
|
.activation("softmax")
|
||
|
.build())
|
||
|
.backprop(true).pretrain(false);
|
||
|
```
|
||
|
|
||
|
## API
|
||
|
|
||
|
{{autogenerated}}
|