Re: Re: Differentiation problem/bug?

*To*: mathgroup at smc.vnet.net*Subject*: [mg69854] Re: [mg69783] Re: Differentiation problem/bug?*From*: Arturas Acus <acus at itpa.lt>*Date*: Tue, 26 Sep 2006 00:59:09 -0400 (EDT)*References*: <eevrea$gfd$1@smc.vnet.net> <200609230844.EAA22439@smc.vnet.net>

Dear Paul, > I never use NonConstants. Also, it is a good idea to avoid using > variables involving capital letters. For calculations where there is > implicit dependence with respect to a variable I use Dt instead. > > inp = 1/4 + 3/8/E^(2 I f) + (3/8) E^(2 I f) - (1/4) E^(-2 I f - I t) + > (1/4) E^(2 I f - I t) - (1/4) E^(I t - 2 I f) + (1/4) E^(2 I f + I t) + > (1/16) E^(-2 I f - 2 I t) + (1/16) E^(2 I f - 2 I t) + > (1/16) E^(2 I t - 2 I f) + (1/16) E^(2 I f + 2 I t) - > 1/8/E^(2 I t) - (1/8) E^(2 I t) > > Dt[t, r] ^= 0; > > Dt[inp, r] // FullSimplify > > Cheers, > Paul > > _______________________________________________________________________ > Paul Abbott Phone: 61 8 6488 2734 > School of Physics, M013 Fax: +61 8 6488 1014 > The University of Western Australia (CRICOS Provider No 00126G) > AUSTRALIA Could Your share any thoughts why this way is more preferable. For example, using Dt I should explicitly write down rules not only for independent variables, but for model parameters also. Thus model variables and parameters mixes up, which for my opinion doesn't look nice from the point of view of logical consistence. Anyway I know You never did it without some motivation. Share please. Sincerely, Arturas Acus > http://physics.uwa.edu.au/~paul -- Arturas Acus <acus at itpa.lt>

**References**:**Re: Differentiation problem/bug?***From:*Paul Abbott <paul@physics.uwa.edu.au>