Error using surf plot

I have a vector of x and y coordinates of the red dots in the image below

I also have a vector of the FWHM at each of these points. I want to create a heat map where at each location x,y, the value if the fwhm and uses a color map.

I thought the following would work

surf(xf,yf,fwhm);

But I get the error

Error using surf (line 57)
Z must be a matrix, not a scalar or vector.

[Jason]

So I've tried the following:

   k=zeros(length(xf),length(yf));

   for i=1:length(xf)
      k(xf(:,i),yf(:,i))=fwhm(:,i);   
   end
   surf(xf,yf,k);

But now get

Subscripted assignment dimension mismatch.
Error in Merlion>pushbutton11_Callback (line 1920)
    k(xf(:,i),yf(:,i))=fwhm(:,i);

Answer 1

[Thorsten]

You can use

K = zeros(length(yf), length(xf)); % note that yf is first, xf is second because 
                                   % zeros use row, column indexing
ind = sub2ind(yf, xf);             % ... same for sub2ind
K(ind) = fwhm;

imshow(K)

[Jason]

Thanks