For loop on two different dimensions, nested for loop?

Hi there, I am trying to create a for loop on two different dimensions.

I have testdata, which is a 1 x 7 cell, and within each cell is a X x 23 table.

I would like to conduct a ttest_bonf test between 7 sets of 3 columns of each X x 23 table, and the column indices I specified by creating the 'column' matrix. E.g. test between column 3, 10 and 17, then a test between columns 4, 11, 18, etc.

How can I save the results of the ttest properly? I am not sure how to do this so I have just been throwing the f index in any possible place on the left side. I am new to Matlab

% create a test dataset similar to mine
id = {'one'; 'two' ;'three'; 'four'};
testtable1=[id array2table(rand(4,22))];
testtable2=[id array2table(rand(4,22))];
testtable3=[id array2table(rand(4,22))];
testdata = {testtable1, testtable2,testtable3}; % this is a 1 x 4 cell with a 4 x 23 table within
h= []; 
p= [];
n = [3 10 17]; % create matrix of column numbers
column = [n; n+1; n+2; n+3; n+4; n+5; n+6];
for c=1:(size(testdata,2))
    for f=1:size(column,1)
        [h(c,:),p(c,:)]{f}=ttest_bonf(table2array([testdata{1,c}(:,column(f,1)) testdata{1,c}(:,column(f,2)) testdata{1,c}(:,column(f,3))]));
    end
end

Answer 1

[Pavan Guntha]

I assume that the requirement is to store the 2 outputs of ttest_bonf (i.e., H, P) into a cell array. In that case the variable needs to be initialized as a cell array. The following code illustrates the idea:

h_p  = {false(size(column,1), size(testdata,2)), zeros(size(column,1), size(testdata,2))};
h_pcell = {h_p, h_p, h_p};

The h_p denotes a cell array in which the first and second elements stores the 1st and 2nd outputs of 'ttest_bonf' function for each input.

h_pcell is also a cell array whose elements are of cell type. It is used to store the outputs of ttest_bonf function for the ‘testdata’ which is a 1x3 cell. The following code illustrates this:

for c=1:(size(testdata,2))
    for f=1:size(column,1)
        [h_pcell{c}{1}(f,:), h_pcell{c}{2}(f,:), ~] = ttest_bonf(table2array([testdata{1,c}(:,column(f,1)) testdata{1,c}(:,column(f,2)) testdata{1,c}(:,column(f,3))]));
    end
end

You may refer to the documentation of cell indexing, multilevel indexing & table indexing for more information on initializing & indexing rules.

[Alexandra Santos]

Thank you so much this really helps!!!