Is this a bug in AbsArg?

*To*: mathgroup at yoda.physics.unc.edu*Subject*: Is this a bug in AbsArg?*From*: mek at guinan.psu.edu (Mark E. Kotanchek)*Date*: Tue, 24 Aug 93 22:02:50 -0400

Hi folks, I was browsing ftp.wri.com and came across Declare.m and AbsArg.m which would appear to help to simplify some equations. However, if I use AbsArg I seem to get some strange and incorrect results. If I execute the following (running Mma 2.1 on my NeXTstation), we get the results: Im[phi] ^= 0 =====> 0 I phi z=Exp[I phi] =====> E I phi Arg[z] =====> Arg[E ] Arg[phi] =====> Arg[phi] If I then load the AbsArg package, my results change to Im[phi] ^= 0 ======> 0 I phi z=Exp[I phi] ======> E Arg[z] ======> 0 Arg[phi] ======> Arg[phi] I was sort of expecting that Arg[z] would give me the phasor angle, phi. I think the resulting answer of zero is dangerously incorrect. Am I correct in this assessment? Will Mathematica ever understand anything other than real algebra? (in a mainstream and supported fashion.) Mark. --- Mark Kotanchek Guidance & Control Dept - 363 ASB Applied Research Lab/Penn State P.O. Box 30 State College, PA 16804 e-mail: mek at guinan.psu.edu (NeXTmail) TEL: (814)863-0682 FAX: (814)863-7843