join - Octave Conditional Merging of matrices -

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i have searched octave function facilitates conditional merging of matrices haven't 1 far. goal using vectors without looping. here example of trying do.

a= [1 1     2 2     3 1     5 2];   b= [1 9     2 10];

i c as

c= [1 1 9     2 2 10     3 1 9     5 2 10];

is there function takes a, b , list of column(s) join on , produce c?

you can use second output of ismember find occurrences of second column of a in first column of b , use grab specific entries second column of b construct c.

[~, inds] = ismember(a(:,2), b(:,1));    c = [a, b(inds,2)];  %//   1     1     9 %//   2     2    10 %//   3     1     9 %//   5     2    10

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