MATLAB: Selecting desired values

datamining

i gave some data
column1    column2    
1,1         3,4
1,2
1,3
;
;
;
1,100       3,100
2,1
;
;
;
2,100          4,100
I want to select 15 values from each 100 ,the values in column should not change,,
(i.e) 1,1..1,15…2,1…2,15…3,1…3,15…4,1..4,15
can u tell how to process

Best Answer

[j1,i1] = ndgrid(1:100,1:4);
ind = [i1(:) j1(:)];
somedata = ind(randperm(numel(i1)),:);
idx = bsxfun(@plus,(1:15)',0:100:numel(i1)-1);
out = somedata(idx,:);
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