Conditionally replace matrix elements from other corresponding matrix

I have two matrices of the same size, X and Y.

I want to replace elements of X if certain conditions are met, with the corresponding element of matrix Y, but crucially without using a loop.

The conditions are: X<Y/exp(1)&&X>1e3

i.e. I was trying something like: X(X<Y/exp(1)&&X>1e3)=Y, but obviously this doesn't work.

What would be the best way to acheive this?

Thanks,

Matt

[Matthew Knights]

That works great. Thanks for the swift answer guys.

Answer 1

[Titus Edelhofer]

Hi Matt,

two changes: you need to use "&" instead of "&&" to work for vectors, and you need to index into Y the same way.

idx = X<Y/exp(1) & X>1e3;
X(idx) = Y(idx);

Titus

Answer 2

[Star Strider]

This runs. I will leave it to you to determine if it works with your matrices:

X = randi(1E+5, 10);
Y = randi(1E+5, 10);

logidx = X<Y/exp(1) & X>1e3;          % Logical Index Array
X(logidx) = Y(logidx);