Re: A Functional Programming Question

• To: mathgroup at smc.vnet.net
• Subject: [mg24744] Re: A Functional Programming Question
• From: Jens-Peer Kuska <kuska at informatik.uni-leipzig.de>
• Date: Wed, 9 Aug 2000 02:31:50 -0400 (EDT)
• Organization: Universitaet Leipzig
• References: <8mdm9v\$5o7@smc.vnet.net>
• Sender: owner-wri-mathgroup at wolfram.com

```Hi,

Transpose[{{a, b, c}, eqns}] /. {b_, a_Equal} :> (#/b & /@ a)

#2*#1^(-1) & @@@ Transpose[{{a, b, c}, eqns}] /. a_Equal/b_ :> (#/b & /@
a)

?

Other more cryptic soutions are welcome.

Regards
Jens

David Park wrote:
>
> Dear MathGroup,
>
> Suppose I have three equations.
>
> eqns = {a x == 0, b y == 0, c z == 0};
>
> I want to divide out the constants a, b, and c. I can do it this way:
>
> eqns[[1]] = (#1/a & ) /@ eqns[[1]];
> eqns[[2]] = (#1/b & ) /@ eqns[[2]];
> eqns[[3]] = (#1/c & ) /@ eqns[[3]];
> eqns
>
> {x == 0, y == 0, z == 0}
>
> Is there a simpler method for doing the calculation in one statement with
> functional programming, say using MapThread over eqns and {a,b,c}? Is there
> any other simple approach?
>
> David Park