Simple recursive assignment
- To: mathgroup at smc.vnet.net
- Subject: [mg15996] Simple recursive assignment
- From: "Peltio" <pelt.ioNOS at PAMiol.it>
- Date: Fri, 19 Feb 1999 03:27:10 -0500
- Organization: Peltio Inc.
- Sender: owner-wri-mathgroup at wolfram.com
Can someone spare a little time for a trivial question?
The assignement
a[0]=1.;
a[1]=2.;
a[n_]:=a[n]=a[n-1]-a[n-2]/n
works fine, all right...
a[5]
0.291667
But how can I achieve the same results when the expression a[n-1]-a[n-2]/n
is stored in a variable expr? The following approach leads to a Recursion
Limit error
expr=b[n-1]-b[n-2]/n;
b[0]=1;
b[1]=2;
b[n_]:=b[n]=expr
b[3]
$RecursionLimit::reclim: etc.
I tried a few combinations with Hold, Release, and so on but I can't fool
the recursion trap.I'm sure it's something trivial I'm missing
Any help would be greatly appreciated.
Thanks
Peltio,
peltioNO at SPAMusa.net
(remove NO SPAM to e-mail me)
- Follow-Ups:
- Re: Simple recursive assignment
- From: "Wolf, Hartmut" <hwolf@debis.com>
- Re: Simple recursive assignment