MATLAB: Substitute values from one matrix to another

MATLABmatrix

Suppose I have a matrix
A = [1 2;1 2;2 4;2 4];
and
B= [1 0.1;2 0.2];
I want to have a matrix 3 * 2 matrix C where *the first column of C is the first column of A *for each row, the value of the second column of C is the value of the second column of B that corresponds to the value of the first column of C.
Thus the output is
C = [1 0.1;1 0.1;2 0.2;2 0.2];
Please advise.

Best Answer

How about using ismember function, like:
[~,loc] = ismember(A(:,1),B(:,1));
C = [A(:,1),B(loc,2)];