RE: A Series test
- To: mathgroup at smc.vnet.net
- Subject: [mg72777] RE: [mg72765] A Series test
- From: "Virgilio, Vincent - SSD" <Vincent.Virgilio at itt.com>
- Date: Fri, 19 Jan 2007 01:37:29 -0500 (EST)
Mathematica 5.2.0.0 on Win XP gives: (a - I*x)/(a + I*x) -----Original Message----- From: carlos at colorado.edu [mailto:carlos at colorado.edu] Sent: Thursday, January 18, 2007 6:02 AM To: mathgroup at smc.vnet.net Subject: [mg72777] [mg72765] A Series test Just curious. Could somebody pls run this script on the latest Mathematica user version (I think it's 5.2) under Windows or Unix and report the results: rho=(x+a*I)/(x-a*I); R=Abs[rho]; s=Series[R,{x,0,4}]; Print[FullSimplify[s,a>=0&&x>=0]//InputForm]; My 5.0 answer (Mac G5 under OS 10.4.8) is SeriesData[x, 0, {1, (-2*I)/a, (-2*(1 + Derivative[2][Abs][-1]))/a^2, (((2*I)/3)*(3 + 6*Derivative[2][Abs][-1] - 2*Derivative[3][Abs][-1]))/ a^3, (2*(3 + 9*Derivative[2][Abs][-1] - 6*Derivative[3][Abs][-1] + Derivative[4][Abs][-1]))/(3*a^4)}, 0, 5, 1] The correct answer is 1. (The result with Simplify is more complicated.) Thanks. ************************************ This e-mail and any files transmitted with it are proprietary and intended solely for the use of the individual or entity to whom they are addressed. If you have received this e-mail in error please notify the sender. Please note that any views or opinions presented in this e-mail are solely those of the author and do not necessarily represent those of ITT, Inc. The recipient should check this e-mail and any attachments for the presence of viruses. ITT accepts no liability for any damage caused by any virus transmitted by this e-mail. ************************************