Re: Simplifying Exponents

*To*: mathgroup at smc.vnet.net*Subject*: [mg43910] Re: Simplifying Exponents*From*: Paul Abbott <paul at physics.uwa.edu.au>*Date*: Sat, 11 Oct 2003 01:33:30 -0400 (EDT)*Organization*: The University of Western Australia*References*: <bm5n64$jab$1@smc.vnet.net>*Sender*: owner-wri-mathgroup at wolfram.com

In article <bm5n64$jab$1 at smc.vnet.net>, wes <wesh at acm.org> wrote: > I am trying to generate rows of a determinant for a Hill's DE. To > do this I generate a series of exponentials of the typical form > > a Exp[I t(-4 + x) - I t x] > > where the coefficient a and integer 4 vary from term to term. There > also may be more terms in the exponent. > > Mathematica resolutely refuses to simplify the exponents, which in > the above case would result in > > a Exp[-4 I t]. > > There are several terms which have different extended exponents but > the same simplified exponents. > > To generate the determinant I need to collect all of the terms having > the same simplified exponent. Have you tried Simplify? E.g. Simplify[Table[a Exp[I t (-n + x) - I t x], {a, -2, 2}, {n, 5}]] Cheers, Paul -- Paul Abbott Phone: +61 8 9380 2734 School of Physics, M013 Fax: +61 8 9380 1014 The University of Western Australia (CRICOS Provider No 00126G) 35 Stirling Highway Crawley WA 6009 mailto:paul at physics.uwa.edu.au AUSTRALIA http://physics.uwa.edu.au/~paul