RE: sum question

*To*: mathgroup at smc.vnet.net*Subject*: [mg91196] RE: [mg91169] sum question*From*: "Jose Luis Gomez" <jose.luis.gomez at itesm.mx>*Date*: Sat, 9 Aug 2008 07:45:00 -0400 (EDT)*References*: <200808081114.HAA11632@smc.vnet.net>

Dear Philip 1) Post your Mathematica code, so that we can help you 2) Take look at this, it might be useful: http://homepage.cem.itesm.mx/lgomez/matecmatica/fp/fp.html http://homepage.cem.itesm.mx/lgomez/matecmatica/funcionalprog.nb Best regards Jose Mexico -----Mensaje original----- De: Kopp, Philip F [mailto:philip-kopp at uiowa.edu] Enviado el: Viernes, 08 de Agosto de 2008 06:14 Para: mathgroup at smc.vnet.net Asunto: [mg91169] sum question Hi, I am trying to work with a rather large sum(>200 terms) in Mathematica , but the program displays some odd behavior. When I multiply each term in the sum by 1, I get 1 for the answer. When I change 1 to 1.0, I get an incredibly large number for the answer. There seems to be some problem with using decimal numbers in this large sum. I tried Rationalize[1.0], and it works. What I am really trying to do is multiply each term by a different number(all less than one) that I calculated in another program. These numbers are in decimal form, so I run into the same problem. When I try rationalize here, it doen't fix the problem. Any other suggestions?

**References**:**sum question***From:*"Kopp, Philip F" <philip-kopp@uiowa.edu>