I am having a second thought. The first solution requires:
- no duplicate dates in A alone and in B alone.
- the dates in A and B shall be sorted and in the same order (ascending or descending). If not, the results will be incorrect. Un-comment the line to see the effect.
A=[1:10;1:10]';
B=[2:2:20;20:20:200]';
%B=B(end:-1:1,:);
C=nan(size(A));
C(:,1)=A(:,1);
IndexA=ismember(A(:,1),B(:,1));
IndexB=ismember(B(:,1),A(:,1));
C(IndexA,2)=B(IndexB,2);
A better solution is below. It still requires no duplicate dates which should be the case based on the task.
A=[1:10;1:10]';
B=[2:2:20;20:20:200]';
B=B(end:-1:1,:);
C=nan(size(A));
C(:,1)=A(:,1);
[Dummy,IndexA,IndexB]=intersect(A(:,1),B(:,1));
C(IndexA,2)=B(IndexB,2);
