新版Matlab中神经网络训练函数Newff的使用方法.docx
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新版Matlab中神经网络训练函数Newff的使用方法
新版Matlab中神经网络训练函数Newff的使用方法
一、介绍新版newff
Syntax
net=newff（P,T,[S1S2...S（N-l）],{TF1TF2...TFNl},BTF,BLF,PF,IPF,OPF,DDF）
Description
newff（P,T,[S1S2...S（N-l）],{TF1TF2...TFNl},BTF,BLF,PF,IPF,OPF,DDF）takesseveral
arguments
PRxQ1matrixofQ1sampleR-elementinputvectors
TSNxQ2matrixofQ2sampleSN-elementtargetvectors
Sizeofithlayer,forN-1layers,default=[].Si（OutputlayersizeSNisdeterminedfromT.）
Transferfunctionofithlayer.（Default='tansig'forTFihiddenlayersand'purelin'foroutputlayer.）
BTFBackpropagationnetworktrainingfunction（default='trainlm'）
BLFBackpropagationweight/biaslearningfunction（default='learngdm'）
IPFRowcellarrayofinputprocessingfunctions.（Default={'fixunknowns','removeconstantrows','mapminmax'}）
OPFRowcellarrayofoutputprocessingfunctions.（Default={'removeconstantrows','mapminmax'}）
DDFDatadivisonfunction（default='dividerand'）
Examples
HereisaproblemconsistingofinputsPandtargetsTtobesolvedwithanetwork.
P=[012345678910];T=[01234321234];
Hereanetworkiscreatedwithonehiddenlayeroffiveneurons.
net=newff（P,T,5）;
Thenetworkissimulatedanditsoutputplottedagainstthetargets.
Y=sim（net,P）;plot（P,T,P,Y,'o'）
Thenetworkistrainedfor50epochs.Againthenetwork'soutputisplotted.
net.trainParam.epochs=50;net=train（net,P,T）;Y=sim（net,P）;plot（P,T,P,Y,'o'）二、新版newff与旧版newff调用语法对比
Example1
比如输入input（6*1000），输出output为（4*1000），那么
旧版定义:
net=newff（minmax（input）,[7,1],{'tansig','purelin'},'trainlm'）;
新版定义:
net=newff（input,output,7,{'tansig','purelin'},'trainlm'）;Example2
比如输入input（6*1000），输出output为（4*1000），那么
旧版定义:
net=newff（minmax（input）,[49,10,1],{'tansig','tansig','tansig'},'traingdx'）;
新版定义:
net=newff（input,output,[49,10],{'tansig','tansig','tansig'},'traingdx'）;
regulations,constructionscaffoldingissafeandreliable,andclimbingladders,liftingCommander1established,full-timesafetyofficer1,responsibleforcheckingthesafetyguaranteemeasures,echoedupanddown,preventaccidents.12）trafficpavementinaccordancewithrequirementsofthetransportsector,andseparatedbyclosedisolationbarrier,constructionandnon-constructionwithbarrierisolation.13）volunteerfireorganizations,employeesconductingfirepreventionpublicityandeducationoftheknowledge,skills,andorganizationalimplementationoffire-fightingandemergencyevacuationplansandwalkthroughs.8.4.5specificconstructionprogramforsafetytechnologyaccordingtotheHebeiprovincialconstructionsafetyinspectionrulesfortheimplementationofrequirementsofthestandard,aseparatespecificconstructionprogramforthefollowing1）scaffolderection,dismantlingprogramme;2）Foundationsupportschemes;3）constructionprojectoftemplateengineering;4）"threetreasures","four"protectionscheme;5）constructionorganizationdesignoftemporarypowersupply;6）installation,demolitionofatowercraneprogramme;7）liftingoperationplan.8.58.5.1environmentalmanagementgoalsofenvironmentalprotection,civilizationconstructionwithoutmajorenvironmentalpollutionaccident,wastegas,wastewater,noise,dust,solid
三、旧版newff使用方法在新版本中使用
提示:
旧版本定义的newff虽也能在新版本中使用，但会有警告，警告如下:
Warning:
NEWFFusedinanobsoleteway.>Inobs_useat18
Innewff>create_networkat127
Innewffat102
SeehelpforNEWFFtoupdatecallstothenewargumentlist.
四、新版newff与旧版newff使用的训练效果对比
旧版本:
旧用法训练次数多，但精度高
新版本:
新用法训练次数少，但精度可能达不到要求
造成上述原因是:
程序里面的权值、阈值的初始值是随机赋值的，所以每次运行的结果都会不一样，
有好有坏。
你可以把预测效果不错的网络的权值和阈值作为初始值。
具体可以查看net.iw{1,1}、net.lw{2,1}、net.b{1}、net.b{2}的值。
regulations,constructionscaffoldingissafeandreliable,andclimbingladders,liftingCommander1established,full-timesafetyofficer1,responsibleforcheckingthesafetyguaranteemeasures,echoedupanddown,preventaccidents.12）trafficpavementinaccordancewithrequirementsofthetransportsector,andseparatedbyclosedisolationbarrier,constructionandnon-constructionwithbarrierisolation.13）volunteerfireorganizations,employeesconductingfirepreventionpublicityandeducationoftheknowledge,skills,andorganizationalimplementationoffire-fightingandemergencyevacuationplansandwalkthroughs.8.4.5specificconstructionprogramforsafetytechnologyaccordingtotheHebeiprovincialconstructionsafetyinspectionrulesfortheimplementationofrequirementsofthestandard,aseparatespecificconstructionprogramforthefollowing1）scaffolderection,dismantlingprogramme;2）Foundationsupportschemes;3）constructionprojectoftemplateengineering;4）"threetreasures","four"protectionscheme;5）constructionorganizationdesignoftemporarypowersupply;6）installation,demolitionofatowercraneprogramme;7）liftingoperationplan.8.58.5.1environmentalmanagementgoalsofenvironmentalprotection,civilizationconstructionwithoutmajorenvironmentalpollutionaccident,wastegas,wastewater,noise,dust,solid
现在给一个完整的例子
%%清空环境变量
clc
clear
%%训练数据预测数据
data=importdata（'test.txt'）;
%从1到768间随机排序
k=rand（1,768）;
[m,n]=sort（k）;
%输入输出数据
input=data（:
1:
8）;
output=data（:
9）;
%随机提取500个样本为训练样本，268个样本为预测样本input_train=input（n（1:
500）,:
）';output_train=output（n（1:
500）,:
）';input_test=input（n（501:
768）,:
）';output_test=output（n（501:
768）,:
）';
%输入数据归一化
[inputn,inputps]=mapminmax（input_train）;
%%BP网络训练
%%初始化网络结构
net=newff（inputn,output_train,10）;
net.trainParam.epochs=1000;
net.trainParam.lr=0.1;
net.trainParam.goal=0.0000004;
%%网络训练
net=train（net,inputn,output_train）;
%%BP网络预测
%预测数据归一化
inputn_test=mapminmax（'apply',input_test,inputps）;
%网络预测输出
BPoutput=sim（net,inputn_test）;
%%结果分析
regulations,constructionscaffoldingissafeandreliable,andclimbingladders,liftingCommander1established,full-timesafetyofficer1,responsibleforcheckingthesafetyguaranteemeasures,echoedupanddown,preventaccidents.12）trafficpavementinaccordancewithrequirementsofthetransportsector,andseparatedbyclosedisolationbarrier,constructionandnon-constructionwithbarrierisolation.13）volunteerfireorganizations,employeesconductingfirepreventionpublicityandeducationoftheknowledge,skills,andorganizationalimplementationoffire-fightingandemergencyevacuationplansandwalkthroughs.8.4.5specificconstructionprogramforsafetytechnologyaccordingtotheHebeiprovincialconstructionsafetyinspectionrulesfortheimplementationofrequirementsofthestandard,aseparatespecificconstructionprogramforthefollowing1）scaffolderection,dismantlingprogramme;2）Foundationsupportschemes;3）constructionprojectoftemplateengineering;4）"threetreasures","four"protectionscheme;5）constructionorganizationdesignoftemporarypowersupply;6）installation,demolitionofatowercraneprogramme;7）liftingoperationplan.8.58.5.1environmentalmanagementgoalsofenvironmentalprotection,civilizationconstructionwithoutmajorenvironmentalpollutionaccident,wastegas,wastewater,noise,dust,solid
%根据网络输出找出数据属于哪类
BPoutput（find（BPoutput<0.5））=0;BPoutput（find（BPoutput>=0.5））=1;
%%结果分析
%画出预测种类和实际种类的分类图
figure
（1）
plot（BPoutput,'og'）
holdon
plot（output_test,'r*'）;
legend（'预测类别','输出类别'）
title（'BP网络预测分类与实际类别比对','fontsize',12）ylabel（'类别标签','fontsize',12）
xlabel（'样本数目','fontsize',12）
ylim（[-0.51.5]）
%预测正确率
rightnumber=0;
fori=1:
size（output_test,2）
ifBPoutput（i）==output_test（i）
rightnumber=rightnumber+1;
end
end
rightratio=rightnumber/size（output_test,2）*100;
sprintf（'测试准确率=%0.2f',rightratio）
regulations,constructionscaffoldingissafeandreliable,andclimbingladders,liftingCommander1established,full-timesafetyofficer1,responsibleforcheckingthesafetyguaranteemeasures,echoedupanddown,preventaccidents.12）trafficpavementinaccordancewithrequirementsofthetransportsector,andseparatedbyclosedisolationbarrier,constructionandnon-constructionwithbarrierisolation.13）volunteerfireorganizations,employeesconductingfirepreventionpublicityandeducationoftheknowledge,skills,andorganizationalimplementationoffire-fightingandemergencyevacuationplansandwalkthroughs.8.4.5specificconstructionprogramforsafetytechnologyaccordingtotheHebeiprovincialconstructionsafetyinspectionrulesfortheimplementationofrequirementsofthestandard,aseparatespecificconstructionprogramforthefollowing1）scaffolderection,dismantlingprogramme;2）Foundationsupportschemes;3）constructionprojectoftemplateengineering;4）"threetreasures","four"protectionscheme;5）constructionorganizationdesignoftemporarypowersupply;6）installation,demolitionofatowercraneprogramme;7）liftingoperationplan.8.58.5.1environmentalmanagementgoalsofenvironmentalprotection,civilizationconstructionwithoutmajorenvironmentalpollutionaccident,wastegas,wastewater,noise,dust,solid
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