% pizza size data
cd('~/Current/Courses/Probcourse/SomeData/DataSets/');
[num, txt, raw]=xlsread('cleanpizzasize.xls');
pmans={'Dominos', 'EagleBoys'}; % manufacturers of pizza; 
%this is a cell array
ndat=size(num, 1);
dsizes=zeros(ndat, 1);
dp=1;
esizes=zeros(ndat, 1);
ep=1;
for i=1:ndat
    if strcmp(txt(i, 2), pmans{1})
        dsizes(dp)=num(i, 5);
        dp=dp+1;
    elseif strcmp(txt(i, 2), pmans{2})
        esizes(ep)=num(i, 5);
        ep=ep+1;
    end
end
ne=ep-1;
nd=dp-1;
figure(2); hist(dsizes(1:nd)); title(pmans{1}); figure(2)
figure(3); hist(esizes(1:ne)); title(pmans{2}); figure(3)
