Re: Multiple Sums in Mathematica

*To*: mathgroup at smc.vnet.net*Subject*: [mg53748] Re: Multiple Sums in Mathematica*From*: Roland Franzius <roland.franzius at uos.de>*Date*: Wed, 26 Jan 2005 04:36:28 -0500 (EST)*Organization*: Universitaet Hannover*References*: <csvir2$avi$1@smc.vnet.net> <ct55mf$e62$1@smc.vnet.net>*Sender*: owner-wri-mathgroup at wolfram.com

Roland Franzius wrote: > Sebastian Brandt wrote: > >>Hello, >> >>I want to perform a nested sum, where the number of summations is not >>specified. I.e., I am looking for a way to implement the sum >> >>sum[ f, {i1, 1, M}, {i2, 1, M}, ..., {in, 1, M} ] >> >>Does anbody know how to do this for arbitrary n? > > > s[n_] := sum[f, Sequence[ > ToExpression["{i" <> # <> ",1,M}" & /@ (ToString /@ Range[n])]]] > Sorry error, must be s[n_] := sum[f, Sequence @@ ToExpression["{i" <> # <> ", 1,M}" & /@ (ToString /@ Range[n])]] -- Roland Franzius