How to correct the code?

Hello!

I wrote this code:

X=rand(5,3);
Y=zeros(5,3);
for k=1:5
    for j=1:3
        if X(k,j)<0.2
            Y(k,j)=-1;
        else
            Y(k,j)=1;
        end
    end
end

I have to write the same code but without using any loop. How to do this?

[Cedric]

Google "MATLAB logical indexing" and understand it, and you'll have the tools for solving your problem.

Answer 1

[KALYAN ACHARJYA]

%Though I am giving the answer here, but please must follow the Google "MATLAB logical indexing" as stated by @Cedric

There are multiple ways, you can do this. One way-

X=rand(5,3);
idx=X<0.2;
Y=ones(5,3);
Y(idx)=-1

[Cedric]

You can eliminate a few things:

X = rand(5,3);
idx = X < 0.2;
Y = ones(5,3);
Y(idx) = -1

also, Pawel, display idx and evaluate class(idx).

[KALYAN ACHARJYA]

Exactly Yes @Cedric sir, I supposed X and Y are given, therefore I replaced original Y with ones.

Thanks!

[pawlo392]

Thank You for help. :)