Re: using predefined expressions in functions [newbie

*To*: mathgroup at smc.vnet.net*Subject*: [mg100211] Re: [mg100167] using predefined expressions in functions [newbie*From*: Bob Hanlon <hanlonr at cox.net>*Date*: Thu, 28 May 2009 04:28:50 -0400 (EDT)*Reply-to*: hanlonr at cox.net

R1 := {x1, y1, z1} R2 := {x2, y2, z2} Don' t use SetDelayed in definition of f f[x1_, y1_, z1_, x2_, y2_, z2_] = R1.R2; f[1, 2, 3, 4, 5, 6] 32 Bob Hanlon ---- ChangMo <nichthierwohne at gmail.com> wrote: ============= Hi, I've been trying to write a function using some predefined expressions, but the function assignment seems to understand the symbols in the expressions as literals. eg., Needs["VectorAnalysis`"] R1 := {x1,y1,z1} R2 := {x2,y2,z2} f[x1_,y1_,z1_,x2_,y2_,z2_] := R1 . R2 f[1,2,3,4,5,6] gives the output x1 x2 + y1 y2 + z1 z2 instead of 32 ( = 1*4 + 2*5 + 3*6 ) Can anyone help me with this? Thanks for your attention. -ChangMo