Um, wow, I think I actually just found a possible answer at long last! (I've been looking for days) Composition of rotate +theta, scale, rotate -theta ... http://cnx.org/content/m21489/latest/?collection=col10685/latest
Hope this is in the right forum. I apologize in advance for my ignorance and imprecise discussion as I am at a major disadvantage, lacking rich mathematical educational background enjoyed by most here.
Background is that I'm curious about calibrating for soft-iron distortion calibration for a...