rotatePolygon.m

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function M2 = rotatePolygon(M , theta)
% Rotates a point in counter clock wise sense
% M is a polygon in the form:
% [px0 py0]
% [px1 py1]
% . . .
% [pxn pyn]

    R = [cos(theta) -sin(theta); sin(theta) cos(theta)];
    M2 = R * M';
end