Re: simple vactor magitude question
- To: mathgroup at smc.vnet.net
- Subject: [mg43773] Re: simple vactor magitude question
- From: bobhanlon at aol.com (Bob Hanlon)
- Date: Sat, 4 Oct 2003 02:04:52 -0400 (EDT)
- References: <blj5e0$1dv$1@smc.vnet.net>
- Sender: owner-wri-mathgroup at wolfram.com
n = 5;
p = Table[Random[], {n+1}];
Sum[p[[i+1]]*i, {i,0,n}]
6.32604
p.Range[0,Length[p]-1]
6.32604
i=0; Fold[(#1+#2*i++)&, 0, p]
6.32604
Bob Hanlon
In article <blj5e0$1dv$1 at smc.vnet.net>, Nathan Moore <nmoore at physics.umn.edu>
wrote:
<< Suppose I generate a 1-d vecctor of "N" numbers, p[i], and now I want to
find the sum of (the vector element * index). I think the syntax should look
something like,
Sum[p[i]*i,{i,0,N}]
but this doesn't seem to be the correct syntax - any help would be
appreciated.