Can I use boolean of a variable on a column of another variable

Hi,

I'm new here to mathworks so I apologise if I don't give all the relevant information right away.

Say I have the variables target(range 1:4) and response(matrix with 10000x16 values)

I want to iterate through each response column and extract the values linked to a specific target and add them to a different vector (Like response(target==2) but for each column seperately)

Right now I have something like:

Resp=[]
For i=1:16
    Resp=[Resp, response(:,i)(target==2)]
    End

This doesn't work. How can i rewrite it?

Answer 1

[Matt J]

Resp=response(target==2,:);

[Femke R]

Thanks!

Answer 2

[Peter O]

Hi, to confirm/rephrase, you're looking to extract 16 separate arrays, each one corresponding to the case where the response matches a target value? If so:

% Setup
target = 1:4;
response = randi(max(target),10000, 16); % Dummy data

% Get 16 different variables, one for each column.
% Because the variables are of potentially different lengths, you'll need to assign them to a cell array.
V = cell(16,1);
my_target = 2;
for ix=1:16
    V{ix} = response(response(:,ix) == my_target, ix);
end

[Femke R]

Yes! Exactly, thanks for the explanation (and a shorter way to add to a vector)