how to rotate image using function notation

How do I write Matlab code using functions to make a rotation on an image? THis is all I've got so far, and I'm probably way off...

    I = 'cameraman.jpg';
    fa = 45;
    f1 = @(xy) xy(:,1) .* cosd(fa) + xy(:,2) .* sind(fa); 
    f2 = @(xy) -xy(:,1) .* sind(fa) + xy(:,2) .* cosd(fa);
    ifcn1 = @(xy) f1(xy);
    
    tform1 = geometricTransform2d(ifcn1);
    Rin = imref2d(size(I),[-1 1],[-1 1]);
    Rout = imref2d(size(I),[-1 1],[-1 1]);
    rho1a = imwarp(I,Rin,tform1,'OutputView',Rout,FillValues=0);

Answer 1

[Chris]

If you're using imwarp, you might as well use imrotate, no? You'd be using the function imrotate() to rotate an image, if that's really your goal.

fa = 45;
I = imread('cameraman.tif');
imrot = imrotate(I,fa);
imshow(imrot)

If you want an anonymous function, like you're using...

rotateImage = @(im, ang) imrotate(im, ang);
imrot = rotateImage(I, fa);
imshow(imrot)

You could also make a standalone function, in a file of the same name or at the bottom of a script, that accepts inputs and outputs the rotated image, and does whatever else you want with the input.

imrot = rotImFun(I, fa);
imshow(imrot);

function out = rotImFun(im, ang)
    out = imrotate(im, ang);
end

[mark palmer]

I think the anonymous function approach is what I needed, thanks!

[mark palmer]

IS there an alternate way to do this with trig functions within an anonymous function? I know it isn't the easiest way, I'm just trying to learn.

[Chris]

I'm unaware of a method that doesn't require a complex series of operations, which a single anonymous function isn't really suited for. That doesn't mean it doesn't exist--it just means I don't have an answer.