Adding options to built-in functions
- To: mathgroup at christensen.cybernetics.net
- Subject: [mg697] Adding options to built-in functions
- From: Jack Goldberg <jackgold at math.lsa.umich.edu>
- Date: Mon, 10 Apr 1995 13:05:27 -0400 (EDT)
Hi group: I would like to add an option to PowerExpand called InverseTrig->False. This option, when evoked would reduce ArcTan[Tan[x]] to x and similarly for the other inverse trigs composed with the trigs. I have done this by defining a new function InverseExpand. I am quite pleased with my result but it strikes me that the proper place for this kind of manipulation is an option to PowerExpand since it is quite in keeping with the positive and negative features of this command. So let me repeat the question: What is the preferred way to introduce your own option to a built in command? Indeed, is it even possible? and if possible, desirable? Jack