Re: NIntegrate a list

*To*: mathgroup at smc.vnet.net*Subject*: [mg52979] Re: [mg52940] NIntegrate a list*From*: DrBob <drbob at bigfoot.com>*Date*: Sat, 18 Dec 2004 04:00:12 -0500 (EST)*References*: <200412171019.FAA16101@smc.vnet.net>*Reply-to*: drbob at bigfoot.com*Sender*: owner-wri-mathgroup at wolfram.com

I'm not sure why you want to integrate functions of x with respect to theta, but it's easily done symbolically: Integrate[x*Sin[x]*{1, 2}, {theta, -Pi, Pi}] {2*Pi*x*Sin[x], 4*Pi*x*Sin[x]} The same thing with NIntegrate doesn't work because NIntegrate needs an integrand that resolves to NUMBERS. If we change theta to x, these work: Integrate[x*Sin[x]*{1, 2}, {x, -Pi, Pi}] NIntegrate[x*Sin[x]*{1, 2}//Evaluate, {x, -Pi, Pi}] but this doesn't: NIntegrate[x*Sin[x]*{1, 2}, {x, -Pi, Pi}] Bobby On Fri, 17 Dec 2004 05:19:17 -0500 (EST), Aaron Fude <aaronfude at yahoo.com> wrote: > Hi, > > I can Integrate this, but apparently not NIntegrate this: > > Integrate[x*Sin[x]*{1, 2}, {theta, -Pi, Pi}] > > but not > > NIntegrate[x*Sin[x]*{1, 2}, {theta, -Pi, Pi}] > > Is there a good way to do this (w/o writing loops)? > > Many thanks! > > Aaron Fude > > > > -- DrBob at bigfoot.com www.eclecticdreams.net

**References**:**NIntegrate a list***From:*"Aaron Fude" <aaronfude@yahoo.com>