function?[at?choose?T]=adaboost（）
%定義樣本
p=[10;-10;01;0-1];
%樣本數(shù)目
numofs=4;
%定義正確分類結(jié)果
y=[11-1-1];
%分類器數(shù)目
numofc=8;
%預(yù)設(shè)的循環(huán)次數(shù)
cycle=5;
%實(shí)際循環(huán)次數(shù)定義為T(mén)
%定義循環(huán)過(guò)程中選擇的函數(shù)下標(biāo)和比重
at=zeros（1cycle）;
choose=zeros（1cycle）;
%每個(gè)樣本在每個(gè)分類器下的label
label=zeros（numofsnumofc）;
%計(jì)算得到label數(shù)組的值
for?i=1:numofs
????for?j=1:numofc
????????label（ij）=h（jp（i:））;
????end
end
%得到每個(gè)函數(shù)錯(cuò)誤樣本的數(shù)組
wrong=zeros（numofcnumofs）;
for?i=1:numofc
????for?j=1:numofs
????????wrong（ij）=（label（ji）~=y（j））;
????end
end
%初始化每個(gè)樣本的權(quán)重
weight=ones（1numofs）/numofs;
%循環(huán)開(kāi)始
%記錄每次循環(huán)中每個(gè)分類器對(duì)應(yīng)的錯(cuò)誤
err_freq=ones（1cycle）;
for?k=1:cycle
????error=zeros（1numofc）;
????for?m=1:numofc
????????error（m）=sum（weight（wrong（m:）==1））;
????end
????[err?index]=min（error）;
????%計(jì)算當(dāng)前選擇的錯(cuò)誤最小的分類器對(duì)應(yīng)的權(quán)值
????choose（k）=index;
????at（k）=log（（1-err）/err）/2;
????%更新權(quán)值
????weight（wrong（index:）==1）=weight（wrong（index:）==1）*exp（0.5）*（1-err）/err;
????weight（wrong（index:）==0）=weight（wrong（index:）==0）*exp（-0.5）*（1-err）/err;
????%標(biāo)準(zhǔn)化
????weight=weight/sum（weight）;
????%計(jì)算當(dāng)前分類器下的錯(cuò)誤頻率如果訓(xùn)練錯(cuò)誤概率已經(jīng)為0，則退出循環(huán)
????err_freq（k）=calerr（numofsylabelatchoosek）;
????if（err_freq（k）==0）
????????break;
????end
end
T=k;
at=at（1:T）;
choose=choose（1:T）;
plot（1:Terr_freq（1:T）‘b*‘）;
title（‘error?vs?round‘）;
xlabel（‘round‘）;
ylabel（‘training?error‘）;
end

?屬性????????????大小?????日期????時(shí)間???名稱
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?????文件???????1534??2013-07-27?11:55??ada2\adaboost.asv

?????文件???????1511??2013-07-27?13:54??ada2\adaboost.m

?????文件????????471??2013-07-27?11:59??ada2\calerr.m

?????文件????????109??2013-07-27?13:51??ada2\classier.asv

?????文件????????187??2013-07-27?13:53??ada2\classier.m

?????文件????????207??2013-07-27?11:10??ada2\h.asv

?????文件????????479??2013-07-27?11:11??ada2\h.m

?????文件?????????99??2013-07-27?11:56??ada2\h1.m

?????文件?????????99??2013-07-27?11:56??ada2\h2.m

?????文件?????????98??2013-07-27?11:56??ada2\h3.m

?????文件?????????98??2013-07-27?11:56??ada2\h4.m

?????文件?????????99??2013-07-27?11:56??ada2\h5.m

?????文件?????????99??2013-07-27?11:56??ada2\h6.m

?????文件?????????98??2013-07-27?11:57??ada2\h7.m

?????文件?????????98??2013-07-27?11:57??ada2\h8.m

?????文件????????110??2013-07-27?13:55??ada2\test.m

?????目錄??????????0??2013-07-27?13:52??ada2

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?????????????????5396????????????????????17