该函数主要显示在神经网络工具箱中，相应的函数还有fixunknowns、mapstd、processpca等函数。 这个函数的说明文件中有这样一节
Before training， itisoftenusefultoscaletheinputsandtargetssothattheyalwaysfallwithinaspecifiedrange.thefunctionmapminmaxscalesinputsandtargettargetate e [1，1 ].thefollowingcodeillustrateshowtousethisfunction.[ pn，ps]=mapminmax(p([tn，ts]=mapminmax(t ) ) net=train(net，pn，tn )； theoriginalnetworkinputsandtargetsaregiveninthematricespandt.thenormalizedinputsandtargetspnandthatarereturnedwillallllfall ill 1 ].thestructurespsandtscontainthesettings，inthiscasetheminimumandmaximumvaluesoftheoriginalinputsandtargets.afterthenthenetettion thepssettingsshouldbeusedtotransformanyfutureinputsthatareappliedtothenetwork.theyeffectivelybecomeapartofthenetwork， justlikethenetworkweightsandbiases.ifmapminmaxisusedtoscalethetargets，theoutputofthenetworkwillbetrainedtoproduceoutputputputututpututs 1 ).toconverttheseoutputsbackintothesameunitsthatwereusedfortheoriginaltargets， usethesettingsts.thefollowingcodesimulatesthenetworkthatwastrainedinthepreviouscode，andthenconvertsthenetworkoutputbackintiode thenetworkoutputancorrespondstothenormalizedtargetstn.theunnormalizednetworkoutputaisinthesameunitsastheoriginaltargetst.iont hetrainingsetdata， thenwheneverthetrainednetworkisusedwithnewinputstheyshouldbepreprocessedwitheminimumandmaximumarecomputedforthetrainin PS.thefollowingcodeappliesanewsetofinputstothenetworkalreadytrained.pnewn=map minmax (anewn=sim (net，pnewn ) )； anew=mapminmax('reverse '，anewn，ts )； For most networks，including feedforwardnet，these steps are done automatically，sothatyouonlyneedtousethesimcommmand .在使用此函数时主要是ateps