MATLAB: Error: Matrix dimensions must agree

MATLABmatrix array

Hi, I've got a function that I'm trying to define, it works for n=0 and n=1 but when I run it for n=2 I keep getting the error matrix dimensions must agree, i cant see what im doing wrong so any help would be great
The question i was given asked me to evaluate a function, and make sure it was adptable so that if it receives vectors of x and y it returns z as a 2D array.
function z = F(n,x,y)
% F Write a comment here that summarises what the function does.
% Write your code for the "F" function here.
[X,Y] = meshgrid(x,y);
if n==0
    z = ones(10);
elseif n==1
    z = (0.5.*X)-Y.^2;
else
    z = 2.*n.*X.*Y.*F((n-1),X,Y)-((2.*n)+1).*F((n-2),X,Y);
    z = z./(2.*n.^2);
end
end

Best Answer

I guess this is what you want. I have changed the input argument to the recursive function calls
function z = F(n,x,y)
% F Write a comment here that summarises what the function does.
% Write your code for the "F" function here.
[X,Y] = meshgrid(x,y);
if n==0
    z = ones(size(X));
elseif n==1
    z = (0.5.*X)-Y.^2;
else
    z = 2.*n.*X.*Y.*F((n-1),x,y)-((2.*n)+1).*F((n-2),x,y);
    z = z./(2.*n.^2);
end
end
Result:
>> F(3, 1:5, 1:5)
ans =
   1.0e+03 *
   -0.0001   -0.0004   -0.0001    0.0014    0.0046
   -0.0014   -0.0077   -0.0153   -0.0222   -0.0265
   -0.0101   -0.0461   -0.1002   -0.1678   -0.2443
   -0.0361   -0.1558   -0.3449   -0.5952   -0.8989
   -0.0936   -0.3927   -0.8752   -1.5286   -2.3402
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