Element wise operation with own function without loops

Question

Radmilka 2015-5-7

评论： Radmilka 2015-5-7

Hello! What is the syntax to do element wise operation with own function? Say, I have matrix A=magic(5) and function myFun(x). And need to do

for i=1:size(A,1)
   for j=1:size(A,2)
        A2=myFun(A(i,j));
   end
end

How to avoid looping?

And one more question. I have an array F or 10 different matrices f1, f2... f10 and my function

function y = Q( f,h,g )
  y=En(conv2(f,h,'full')-g)/En(g);
end

How can I apply this function to each matrix of this array simultaneously and without loops?

Answer 1

Guillaume 2015-5-7

First question, use arrayfun:

A2 = arrayfun(@myfunc, A);

Second question, assuming your 10 different matrices are held in cell array F, use cellfun:

h = ??? %something
g = ??? %something else
F2 = cellfun(@(f) Q(f, h, g), F, 'UniformOutput', false); %assuming that Q returns non-scalar.

Radmilka 2015-5-7

I'll try this :) Thanks a lot for fast reply!