How to use an efficient lookup table

Hey guys,

I have two matrices that are imported from a .csv via the readtable or readcell command, I will have to check later which one I need later. I only know that I cannot use readmatrix

One contains names of crossings that can be a mix from letters and numbers.

A = [10581, 1681, 2145, d1q46]

The other matrix contains the streets with start and endpoints that are the streets.

B(:,1)= [d1q46; 10581; 1681; 2145; 10581; 1681]

I need the vector that outputs the indices of matrix A when the elements of A and B are equal. So I need the incidence matrix

At the moment I', trying to do this with two for loops, but it takes about 10 Minutes to finish, because both matrices have about 10.000 elements and may even be much bigger in the future.

Is it possible to do this faster? My only other option would be to let it calculate and save the result somewhere. Which would be okay but not great.

With kind regards

Phillipp

Edit: Pressed enter before finished checking the question for errors.

Answer 1

[Phillipp]

I did a little more reasearch and found out how to do it.

[~,loc] = ismember (B.nameofcolumn,A.nameofcolumn);
loc