How to use find() to find the corresponding output (not index!) of an input value

I am given a table with 2 columns - one contains P_in, the other P_out:

P_in  = table(:,1)
P_out = table(:,2)

I want MATLAB to find the corresponding values of P_out to a set of P_in. I.e. I have P_in2 which is a subset of P_in. I want MATLAB to return the corresponding output values. I tried:

P_in2 = find(table(P_in2,2));

I get an error: Subscript indices must either be real positive integers or logicals.

So apparently find() can only deal with integers. Also, I think, find() only returns indices. How can I solve this problem?

Answer 1

[Jyotish Robin]

Hi Luki,

You could try using the functions "arrayfun" and "find" together to resolve the issue.

The relevant indices can be found using the following command:

>>idxs = arrayfun(@(x)find(P_in==x,1),P_in2)

Now you can use these indices to index into P_out as follows:

>>ans = P_out(idxs);

Hope this helps!