Hi Jason,
Please see the following sample code, which demonstrates that you can declare the "rect" variable just once and still achieve the expected result. The spaces and commas in the vector are both valid MATLAB syntax for creating an array, and they are functionally equivalent.
% Sample values for the rectangle parameters
margin = 10;
xcen = 50;
ycen = 75;
hw = 20;
% Create a sample image (a 200x200 black image for this example)
IM = zeros(200, 200);
% Create a figure and axes
figure;
ax = axes;
rect=[margin+xcen+hw,margin+ycen+hw,2*hw,2*hw]; %[x, y, width, height]
rectangle(ax,'Position',rect,'EdgeColor','y');
ImTL = imcrop(IM, rect);
