plotprobs.m

The goal of SPID is to provide the user with tools capable to simulate, preprocess, process and clas

function plotprobs(X,y,alpha,pars)

grain=25;
K=length(unique(y));c=K-1;
fignr=1;

for i=1:K, 
  ic=find(y==i);
  xplot{i}=X(ic,:);
end

Xmin = min(X,[],1);
Xmax = max(X,[],1);
Xs1 = (Xmin(1)):((Xmax(1)-Xmin(1))/grain):(Xmax(1));
Xs2 = (Xmin(2)):((Xmax(2)-Xmin(2))/grain):(Xmax(2));
[X1,X2] = meshgrid(Xs1,Xs2);
Xp=[ones(length(X1(:)),1) X1(:) X2(:)];
N=size(Xp,1);

[N,d]=size(Xp);

alphamat=reshape(alpha,c,size(X,1))'; % matrix notation
p=alphaprobs(Xp,y,alphamat,pars,[ones(size(X,1),1) X]);

if nargin > 1,
    figure(fignr);clf;
else
    figure();clf;
end
colormap('default')
colmark{1}='k*' ;
colmark{2}='rv' ;
colmark{3}='b.' ;
colmark{4}='g+' ;

for i=1:K-1,         
    eval(['subplot(' num2str(K) '1' num2str(i) ');']);
    pl=p(:,i)';
    pl=reshape(pl,size(X1,2),size(X2,1));pl(1)=0;pl(end)=1;
    
    surf(X1,X2,pl);shading interp;hold on;

    for j=1:K,
       plot3(xplot{j}(:,1),xplot{j}(:,2),ones(size(xplot{j},1),1),colmark{j});
    end

    axis([Xmin(1) Xmax(1) Xmin(2) Xmax(2)]);
    view(0,90);
    title(['clasprob' num2str(i)]);
end

i=K;

eval(['subplot(' num2str(K) '1' num2str(i) ');']);
pl=1-sum(p,2);
pl=reshape(pl,size(X1,2),size(X2,1));pl(1)=0;pl(end)=1;
surf(X1,X2,pl);shading interp;hold on;
for j=1:K,
 plot3(xplot{j}(:,1),xplot{j}(:,2),ones(size(xplot{j},1),1),colmark{j});
end

axis([Xmin(1) Xmax(1) Xmin(2) Xmax(2)]);
view(0,90);
title(['clasprob' num2str(i)]);