MATLAB: Rotating and shifting a meshgrid

MATLABmatrixmatrix manipulationmeshgridrotationshifting

Hello,
I have a 257×257 X,Y coordinate meshgrid that I need to rotate by 10 degrees (counterclockwise) and then move it along the x and y axis by adding a certain number to it (175.5362) in order to move it to the right location. This is what I have so far:
%Create the meshgrid
Xinit = 0:3125:800000;
Yinit = 0:3125:800000;
[Xq,Yq] = meshgrid(Xinit,Yinit);
When doing it in vector arrays I would do this:
theta=-10; %TO ROTATE CLOCKWISE BY X DEGREES
R=[cosd(theta) -sind(theta); sind(theta) cosd(theta)]; %CREATE THE MATRIX
rotXY=XY*R'; %MULTIPLY VECTORS BY THE ROT MATRIX
But this is a 257×257 matrix and I get this subsequently:
"Error using *
Inner matrix dimensions must agree."
I assume the second part of my question is just a matter of doing this:
%SHIFTING
Xq=Xq+175.5362;
Yq=Yq+175.5362;
Apologies if this is something very simple that I am missing again,
Thank you,
Pavlos

Best Answer

One approach: 
%Create the meshgrid
Xinit = 0:3125:800000;
Yinit = 0:3125:800000;
[Xq,Yq] = meshgrid(Xinit,Yinit);
Z = sin(Xq/40000) .* cos(Yq/40000);                     % ‘Z’ To Provide A Surface
figure
mesh(Xq,Yq,Z)                                           % Original
grid on
XY = [Xq(:) Yq(:)];                                     % Create Matrix Of Vectors
theta=-10; %TO ROTATE CLOCKWISE BY X DEGREES
R=[cosd(theta) -sind(theta); sind(theta) cosd(theta)]; %CREATE THE MATRIX
rotXY=XY*R'; %MULTIPLY VECTORS BY THE ROT MATRIX 
Xqr = reshape(rotXY(:,1), size(Xq,1), []);
Yqr = reshape(rotXY(:,2), size(Yq,1), []);
%SHIFTING
Xqrs = Xqr+175.5362;
Yqrs = Yqr+175.5362;
figure
mesh(Xqrs, Yqrs, Z)                                     % Rotated & Shifted
grid on
See if that gives you the result you want.
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