Re: How to define a list of functions/variables
- To: mathgroup at smc.vnet.net
- Subject: [mg102209] Re: [mg102174] How to define a list of functions/variables
- From: DrMajorBob <btreat1 at austin.rr.com>
- Date: Sat, 1 Aug 2009 04:01:22 -0400 (EDT)
- References: <200907310957.FAA19516@smc.vnet.net>
- Reply-to: drmajorbob at bigfoot.com
The output of a statement like
f[anything_]:=anythingElse
is Null.
That is, the result of SetDelayed is Null.
Bobby
On Fri, 31 Jul 2009 04:57:11 -0500, Haibo Min <haibo.min at gmail.com> wrote:
> Hello, everyone.
>
> I want to define a list of variables "qi" and "Omegai", where q and
> Omega are both vectors and "i" denotes the ith vector, i.e.,
> qi[t]={qi1[t],qi2[t],qi3[t]},
> Omegai[t]={Omegai1[t],Omega2[t],Omegai3[t]}.
>
> then I use the following code.
>
> eqns[n_Integer] /; Positive[n] :=
> Table[{Subscript[q, i][t_] := {Subscript[q, i1][t],
> Subscript[q, i2][t], Subscript[q, i3][t]},
> Subscript[\[Omega], i][t_] := {Subscript[\[Omega], i1][t],
> Subscript[\[Omega], i2][t], Subscript[\[Omega], i3][t]}}, {i, n}]
>
> but it shows that: eqns[2]={{Null, Null}, {Null, Null}}
> why?
>
> Thanks!
>
> Regards,
> Haibo
>
--
DrMajorBob at bigfoot.com