"rotate(h,direction,alpha) rotates the graphics object h by alpha degrees. Specify h as a surface, patch, line, text, or image object."
You attempted to rotate an annotation()
By the way, have you looked at rectangle() instead of annotation() ? I am not sure it can be rotate()'d either, but it can be easier to use than annotation() .
I am certain that it is possible to parent a rectangle() object to a hgtransform() and set the transform matrix to do a rotation.
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