MATLAB: Find matching indexes

matchingmatrix

I have two matrices:

A: x rows and 5 columns
B: x rows and 6 columns (the first column contains indexes)

The values of the matrix A are included in the matrix B. I would like to find the indexes of the matrix A (one row)

Best Answer

Index_find = find(ismember(A,B));

Related Solutions

MATLAB: Obtain row and column indices of non-zero matrix elements

Of course, there is, use the two output version of find:

[row, col] = find(A)

MATLAB: Simil to VLOOKUP (but ismember index 0)

A simple way would be to fill the 2nd column of A with NaNs and replace some with logical addressing using ismember:

A=[1; 4; 3; 2; 5; 6; 7; 8; 9; 10]; %changed to make sure it works regardless of ordering



B=[2 100; 7 500; 4 300]; %changed to make sure it works regardless of ordering
A = [A nan(size(A, 1), 1)];
[row, locb] = ismember(A, B(:, 1));
A(row, 2) = B(locb(row), 2)

Another option is to use intersect instead of ismember and just use the indices it returns:

A=[1; 4; 3; 2; 5; 6; 7; 8; 9; 10]; %changed to make sure it works regardless of ordering
B=[2 100; 7 500; 4 300]; %changed to make sure it works regardless of ordering
A = [A nan(size(A, 1), 1)];
[~, ia, ib] = intersect(A, B(:, 1));
A(ia, 2) = B(ib, 2)

Best Answer

Related Solutions

MATLAB: Obtain row and column indices of non-zero matrix elements

MATLAB: Simil to VLOOKUP (but ismember index 0)

Related Question