Vectorize a for loop

Hi. How can I speed up the process of my for loop code.

function [missingCase] = CaseChecking(bimage)

missingCase = '';
for img = 1:66
    mapList = xlsread('map.xlsx',img);
    counter=0;
    for i = 1:200
        if (~bimage(mapList(i,2),mapList(i,1)))
            counter=counter+1;
        end
    end
    if counter<50
        missingCase = img;
        break
    end
end

Answer 1

[Andrei Bobrov]

Please attach your data (bimage,map.xlsx - small example) as mat-file and xlsx-file.

ml = zeros(200,2,66);
for ii = 1:size(ml,3)
    ml(:,:,ii) = xlsread('map.xlsx',ii);
end
mlw = permute(ml(:,end:-1:1,:),[1,3,2]);
out = find(~bimage(sub2ind(size(bimage),mlw(:,:,1),mlw(:,:,2))) < 50,'first',1);

[Ramon Ticzon]

These are the sample files. Thank you

Answer 2

[Andrei Bobrov]

Solution for attached data:

[~,sheets] = xlsfinfo('MapList.xlsx');
n = numel(sheets);
ml = cell(n,1);
for ii = 1:n
    ml{ii} = xlsread('MapList.xlsx',ii);
end
jj = repelem((1:n)',cellfun('size',ml,1));
A = cat(1,ml{:});
k = accumarray(jj,(1:size(A,1))',[],...
               @(x) sum(~bimage(sub2ind(size(bimage),A(x,2),A(x,1)))));
out = find(k < 50,'first',1);

[Ramon Ticzon]

where is the variable 'missingCase'? also the 'img' variable.

[Ramon Ticzon]

Hi. Im having an error.

Error in CaseChecking (line 14)

@(x) sum(~bimage(sub2ind(size(bimage),A(x,2),A(x,1)))));