Re: Sum

*To*: mathgroup at smc.vnet.net*Subject*: [mg55225] Re: Sum*From*: "Peltio" <peltio at trilight.zone>*Date*: Thu, 17 Mar 2005 03:28:50 -0500 (EST)*References*: <d192qe$ng4$1@smc.vnet.net>*Reply-to*: "Peltio" <peltioNOSPAM at despammed.com.invalid>*Sender*: owner-wri-mathgroup at wolfram.com

"mjumbo" wrote >x = Exp[-k] >Sum[x, {k, 0, Infinity}] > >don't? What should I do to make it work? Sum has the attribute HoldAll. So you need to evaluate the expression x passed to it if yuo want it to see what's inside it. Sum[Evaluate[x], {k, 0, Infinity}] cheers, Peltio