Cell Array and function handle

Question

Look at the below code:

for i=1:2
if i == 1
    F{i}= @(x) x(i)+x(i+1);
else
    F{i}= @(x) x(i-1)-x(i)+2;
end
end

I wanted to have stored in F something like F={@(x) x(1)+x(2);@(x) x(1)-x(2)+2;}. How should I edit my code to achieve this? Can anyone help me?

Answer 1

I think it's a displaying issue, rather than a functional issue.

Doing this:

for i = 1:2
    if i == 1
        F{i}= @(x) x(i)+x(i+1);
    else
        F{i}= @(x) x(i-1)-x(i)+2;
    end
end

actually gives the correct results:

>> F{1}([1 2 3 4])
ans =
     3    % == x(1)+x(2), i==1

>> F{2}([1 2 3 4])
ans =
     1    % == x(1)-x(2)+2, i==2

But the functions are displayed "incorrectly":

>> F
F = 
    @(x)x(i)+x(i+1)    @(x)x(i-1)-x(i)+2

If you want them to be displayed correctly as well, you'll have to get messy:

for i=1:2

    if i == 1        
        F{i} = str2func(['@(x)x(' num2str(i) ')+x(' num2str(i+1) ')']);
    else        
        F{i} = str2func(['@(x)x(' num2str(i-1) ')-x(' num2str(i) ')+2']);
    end
end

Results:

>> F
F = 
    @(x)x(1)+x(2)    @(x)x(1)-x(2)+2