1、機(jī)器學(xué)習(xí)實(shí)驗(yàn)報(bào)告實(shí)驗(yàn)一、ID3算法.實(shí)驗(yàn)?zāi)康模毫私獠⒄莆誌D3算法。.實(shí)驗(yàn)內(nèi)容：編程實(shí)現(xiàn)ID3算法。.實(shí)驗(yàn)結(jié)果。實(shí)驗(yàn)程序：function tree=ID3(T,N_V)m,n=size(T);C=zeros(1,n);for i=1:nC(i)=max(T(:,i);endPe=zeros(1,C(n);Ee=0;for i=1:C(n)Pe(i)=length(find(T(:,n)=i)/m;if Pe(i)=0Ee=Ee-(Pe(i)*log2(Pe(i);endendP=zeros(n-1,max(C(1:n-1),C(n);E=zeros(1,n-1);G=zeros(1,n-1)

2、;nj=0;for i=1:n-1for j=1:C(i)nj=length(find(T(:,i)=j);for k=1:C(n)counter=0;for ii=1:mif (T(ii,i)=j&T(ii,n)=k)counter=counter+1;end endP(i,j,k)=counter/nj;if P(i,j,k)=0E(i)=E(i)-(nj/m)*P(i,j,k)*10g2(P(i,j,k);endendendG(i)=Ee-E(i);endbest=0;BestTag=0;for i=1:n-1if G(i)bestbest=G(i);BestTag=i; endendt

3、ree.rname=N_V(1,BestTag);for ii=1:C(BestTag)temp=0;tree.branchii=;tree.bnameii=;for i=1:mif (T(i,BestTag)=ii) if (temp=0) temp=T(i,n);elseif (temp=T(i,n)tree.branchii=ID3(T(T(:,BestTag)=ii,:),N_V);tree.bnameii=N_V(ii+1,BestTag); break ; endendend if isempty(tree.bnameii) tree.branchii=N_V(temp+1,n);

4、tree.bnameii=N_V(ii+1,BestTag); endend對(duì)于下表:DayOutlookTemperatureHumidityWindyPlayTennisD1SunnyHotHighWeakNoD2SunnyHotHighStrongNoD3OvercastHotHighWeakYesD4RainMildHighWeakYesD5RainCoolNormalWeakYesD6RainCoolNormalStrongNoD7OvercastCoolNormalStrongYesD8SunnyMildHighWeakNoD9SunnyCoolNormalWeakYesD10Ra

5、inMildNormalWeakYesD11SunnyMildNormalStrongYesD12OvercastMildHighStrongYesD13OvercastHotNormalWeakYesD14RainMildHighStrongNo轉(zhuǎn)化為程序輸入N_V= outlook sunny overcast rain:temperaturehumidityhothighweak no;mildnormalstrongcoolNAS NAS NAS windyyes;class ;T= 1 1 1 1 1;1 1 2 1;1 1 1 2;2 1 1 2;3 2 1 2;23 2 2 1;

6、3 2 2 2;2 1 1 1;3 2 1 2;2 2 1 2;2 2 2 2;2 1 2 2;1 2 1 2;2 1 2 1;O=ID3(T,N_V);其中：第一列 1、2、3分別對(duì)應(yīng)sunny 、overcast 、rain ；第二列 1、2、3分別 對(duì)應(yīng)hot 、mild 、cool ；第三列 1、2 分別對(duì)應(yīng)high 、normal 、cool ；第四 列1、2分別對(duì)應(yīng)weak 、strong ；第五列1、2分別對(duì)應(yīng)no 、yes。程序輸出： 0Sn3(T,N_V)rnane:out IdokJ)branch: 1x1 struct 1x1 cell 1x1 struct bnaae:

7、 1x1 cell 1x1 cellF 1x1 cell 0.bna*e:ans =臚 simny Jarts =overcastarts 二 |rainR O.brancliiaxis -maMe:humiditybranch1 11 cell #1 cell bnane: 1x1 cell! !1x1 cellHans =yesmae: .indy”branchibnaiie:Ixl cellI 1x1 cell!(1x1cellbranchibnaiie:Ixl cellI 1x1 cell!(1x1cell1x1 cell實(shí)驗(yàn)P神經(jīng)網(wǎng)絡(luò).實(shí)驗(yàn)?zāi)康模毫私獠⒄莆?實(shí)驗(yàn)?zāi)康模毫私獠⒄莆誃P神

8、經(jīng)網(wǎng)絡(luò).實(shí)驗(yàn)內(nèi)容：編程實(shí)現(xiàn)BP神經(jīng)網(wǎng)絡(luò)。.實(shí)驗(yàn)結(jié)果。實(shí)驗(yàn)程序：Wac=0.1;Wbc=0.1;Wc0=0.1;Wcd=0.1;Wd0=0.1;L=0.3;I=0.9;X=1 0;0 1;T=1 0;DWcd=0;DWd0=0;DWac=0;DWbc=0;DWc0=0;N=1000;OUT=zeros(2,N);for i=1:NSc(1)=Wac*X(1,1)+Wbc*X(1,2)+Wc0;Oc(1)=1/(1+exp(-Sc(1);Sd(1)=Wcd*Oc(1)+Wd0;Od(1)=1/(1+exp(-Sd(1);Ed(1)=Od(1)*(1-Od(1)*(T(1)-Od(1);Ec(1)=

9、Oc(1)*(1-Oc(1)*Ed(1);DWcd=L*Ed(1)*Oc(1)+I*DWcd;DWd0=L*Ed(1)+I*DWd0;DWac=L*Ec(1)*X(1,1)+I*DWac;DWbc=L*Ec(1)*X(1,2)+I*DWbc;DWc0=L*Ec(1)+I*DWc0;Wcd=Wcd+DWcd;Wd0=Wd0+DWd0;Wac=Wac+DWac;Wbc=Wbc+DWbc;Wc0=Wc0+DWc0;OUT(1,i)=Od(1);Sc(2)=Wac*X(2,1)+Wbc*X(2,2)+Wc0;Oc(2)=1/(1+exp(-Sc(2);Sd(2)=Wcd*Oc(2)+Wd0;Od(2)=1/(1+exp(-Sd(2);Ed(2)=Od(2)*(1-Od(2)*(T(2)-Od(2);Ec(2)=Oc(2)*(1-Oc(2)*Ed(2);DWcd=L*Ed(2)*Oc(2)+I*DWcd;DWd0=L*Ed(2)+I*DWd0;DWac=L*Ec(2)*X(2,1)+I*DWac;DWbc=L*Ec(2)*X(2,2)+