epoch如何设置_matlab神经网络训练时，如何选择迭代次数的问题

MATLAB是一种面向对象的语言，所以你创建了一个神经网络net的object, 下面我教给你如何修改参数。你明白原理以后，可以修改任意参数：

首先我们运行一个简单的神经网络例程：

[x,t] = simplefit_dataset;

net = feedforwardnet(10) %我故意把封号去掉，想看一下net到底是什么

结果如下：

net =

Neural Network

name: 'Feed-Forward Neural Network'

efficiency: .cacheDelayedInputs, .flattenTime,

.memoryReduction

userdata: (your custom info)

dimensions:

numInputs: 1

numLayers: 2

numOutputs: 1

numInputDelays: 0

numLayerDelays: 0

numFeedbackDelays: 0

numWeightElements: 10

sampleTime: 1

connections:

biasConnect: [1; 1]

inputConnect: [1; 0]

layerConnect: [0 0; 1 0]

outputConnect: [0 1]

subobjects:

inputs: {1x1 cell array of 1 input}

layers: {2x1 cell array of 2 layers}

outputs: {1x2 cell array of 1 output}

biases: {2x1 cell array of 2 biases}

inputWeights: {2x1 cell array of 1 weight}

layerWeights: {2x2 cell array of 1 weight}

functions:

adaptFcn: 'adaptwb'

adaptParam: (none)

derivFcn: 'defaultderiv'

divideFcn: 'dividerand'

divideParam: .trainRatio, .valRatio, .testRatio

divideMode: 'sample'

initFcn: 'initlay'

performFcn: 'mse'

performParam: .regularization, .normalization, .squaredWeighting

plotFcns: {'plotperform', plottrainstate, ploterrhist,

plotregression}

plotParams: {1x4 cell array of 4 params}

trainFcn: 'trainlm'

trainParam: .showWindow, .showCommandLine, .show, .epochs,

.time, .goal, .min_grad, .max_fail, .mu, .mu_dec,

.mu_inc, .mu_max

weight and bias values:

IW: {2x1 cell} containing 1 input weight matrix

LW: {2x2 cell} containing 1 layer weight matrix

b: {2x1 cell} containing 2 bias vectors

methods:

adapt: Learn while in continuous use

configure: Configure inputs & outputs

gensim: Generate Simulink model

init: Initialize weights & biases

perform: Calculate performance

sim: Evaluate network outputs given inputs

train: Train network with examples

view: View diagram

unconfigure: Unconfigure inputs & outputs

evaluate:       outputs = net(inputs)

>>

现在明白了么？一个object，通常有属性(properties)和方法(methods), 这里的functions类似于属性，所以你可以这样修改你的目标(根据需要修改数值)：

net.trainParam.epochs = 1000; %训练次数

net.trainParam.show = 10; %显示次数

net.trainParam.goal = 0.1; %训练目标

.....

然后调用train函数即可