Edit: Turns out in my use case I should use ComplexExpand instead of Simplify. My broader question is still worth answering, but as noted in the comments it has been asked before.
I want the black box of Mathematica to tell me what it's doing with Simplify, so that I can pick and choose which parts of it to use via TransformationOptions.
Ideally AbsoluteOptions[Simplify,TransformationOptions] would do this, but that appears to not (yet?) work.
My use case: I want to simplify all terms in a 1000+ term sum without attempting to factor anything. By default Simplify "tries expanding, factoring, and doing many other transformations on expressions" (from the Simplify doc). I suspect factoring is slowing things way down, so I want to use the option TransformationOptions->{stuff besides factoring}.
Here's an example to demonstrate the slowness of Simplify (note this still runs way faster than my real use case):
Simplify[Conjugate[Sum[Exp[I n x], {n, 1000}]],
x \[Element] Reals] // Timing
(* 4.76 seconds *)
In sum: I want to Simplify without factoring. But if you know another way to speed up this sort of simplification, that would be nice too.
AbsoluteOptionsoften does not produce desired results. – bbgodfrey Jul 28 '18 at 21:20ComplexExpanddoes what you want, andSimplifyappears to call it. – bbgodfrey Jul 28 '18 at 22:33Simplifyon each term?? – Marius Ladegård Meyer Jul 28 '18 at 22:35ComplexExpandis all I needed. I guess I don't needSimplifynow. Thanks! – Max Jul 28 '18 at 22:53