Why so slow and not getting faster

*To*: mathgroup at smc.vnet.net*Subject*: [mg113238] Why so slow and not getting faster*From*: Sam Takoy <sam.takoy at yahoo.com>*Date*: Wed, 20 Oct 2010 04:07:21 -0400 (EDT)

Hi, I ran the following code on two machines (linux and windows) under identical versions - 7.0.1.0. On the windows machine, the code takes 10-15 seconds on each run. On the linux maxhine, the first run took 6 seconds and all subsequent runs are nearly instantaneous (< 1/10 sec). 1. I accept that my windows machine is slower, but why doesn't it show similar acceleration in subsequent runs? 2. Even 6 seconds I think is too high. Are these very simple integrations for Mathematica? Many thanks in advance, Sam FourierCoefficients[f_, order_] := Module[{first, reim}, first = 1/(2 \[Pi]) Integrate[f[a], {a, -\[Pi], \[Pi]}]; Print[first]; reim = Table[(Print[n]; 1/\[Pi] Integrate[f[a]*E^(I*n*a), {a, -\[Pi], \[Pi]}]), {n, 1, order}]; Join[{first}, Map[ComplexExpand[{Re[#], Im[#]}] &, reim]]] g[a_] := 1/32 (7 - 11 Cos[2 a] - 8 Cos[4 a] - 3 Cos[6 a]) FourierCoefficients[g, 5]