Find the rows that have common elements for 4 arrays

Dear all, I have 4 files and created 4 arrays, I wanted to make a new array that includes the rows that their last column elements have same values. I used ismember commadn for 2 arrays but not sucessful for 4 files. Please find the files attached and my code as the following:

in1 = readtable ('in1_dmp.txt');
in2 = readtable ('in2_dmp.txt');
out1 = readtable ('out1_dmp.txt');
out2 = readtable ('out2_dmp.txt');

maxCas=5000;

in1 =  table2array (in1);
casNum_m = in1(:,9);
btchNum_m = in1(:,10);

for i = 1 : length(btchNum_m)
     eventNUm=(casNum_m+maxCas.*(btchNum_m-1));   
end
    %Delete  column
    in1(:,9:11) = [];
    %Add new column
    in1 = [in1 eventNUm];


    in2 =  table2array (in2);
casNum_m = in2(:,9);
btchNum_m = in2(:,10);

for i = 1 : length(btchNum_m)
     eventNUm=(casNum_m+maxCas.*(btchNum_m-1));   
end
    %Delete  column
    in2(:,9:11) = [];
    %Add new column
    in2 = [in2 eventNUm];


out1 = table2array(out1);
casNum_n = out1(:,9);
btchNum_n = out1(:,10);

for i = 1 : length(btchNum_n)
     eventNUm=(casNum_n+maxCas.*(btchNum_n-1));   
end
    %Delete  column
    out1(:,9:11) = [];
    %Add new column
    out1 = [out1 eventNUm];


    out2 = table2array(out2);
casNum_n = out2(:,9);
btchNum_n = out2(:,10);

for i = 1 : length(btchNum_n)
     eventNUm=(casNum_n+maxCas.*(btchNum_n-1));   
end
    %Delete  column
    out2(:,9:11) = [];
    %Add new column
    out2 = [out2 eventNUm];

idx1 = ismember(in1(:,9),in2(:,9));
in1_com = in1(idx1,:);
% 
% idx2 = ismember(in2(:,9),in1(:,9));
% in2_com = in2(idx2,:);
% 
% idx3 = ismember(out1(:,9),out2(:,9));
% out1_com = out1(idx3,:);
% 
% idx4 = ismember(out2(:,9),out1(:,9));
% out2_com= out2(idx4,:);

[Jan]

What is the purpose of this loop:

for i = 1 : length(btchNum_m)
     eventNUm=(casNum_m+maxCas.*(btchNum_m-1));   
end

The body does not depend on i, so running it repeatedly is a waste of time only. This occurs several times, which is even more confusing.

[Hamid]

@Jan Thank you for the comment. The aim was to create a new column by multiplying two columns. At the end I have 4 variables which I want to know which rows has the same value in their last columns as attached.

Answer 1

[Jan]

What about:

intesect(intersect(intersect(in1(:,9), in2(:,9)), out1(:,9)), out2(:,9))

[Hamid]

Thanks again. This line gives the values of the last column that are in common perfectly but I want the rows.

[Jan]

Which rows? Do you mean the 4 vectors of indices of the common values according to the 4 variables?

[Hamid]

the rows that have the elements of these common elements.

common=intesect(intersect(intersect(in1(:,9), in2(:,9)), out1(:,9)), out2(:,9))

I used ismember to find them but faced with the following problem. Could you please take a look? Many thanks.

https://ch.mathworks.com/matlabcentral/answers/1758835-wrong-output-of-ismember-command?s_tid=srchtitle