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Re: "vector" Map[] / functional outer product?

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  • Subject: [mg83785] Re: [mg83746] "vector" Map[] / functional outer product?
  • From: DrMajorBob <drmajorbob at bigfoot.com>
  • Date: Fri, 30 Nov 2007 05:25:51 -0500 (EST)
  • References: <32749756.1196391784436.JavaMail.root@mp06>
  • Reply-to: drmajorbob at bigfoot.com

Transpose@Outer[#1@#2 &, {f, g}, {a, b, c}]

{{f[a], g[a]}, {f[b], g[b]}, {f[c], g[c]}}

Composition[Through, {f, g}] /@ {a, b, c}

{{f[a], g[a]}, {f[b], g[b]}, {f[c], g[c]}}

Through /@ {f, g} /@ {a, b, c}

{{f[a], g[a]}, {f[b], g[b]}, {f[c], g[c]}}

Bobby

On Thu, 29 Nov 2007 05:36:04 -0600, Mitch Murphy <mitch at lemma.ca> wrote:

>
> greetings,
>
> is there a simpler way to express
>
> 	{f@#,g@#}& /@ {a,b,c}
>
> 	-> {{f[a],g[a]},{f[b],g[b]},{f[c],g[c]}}
>
> ie. is there some mathematica function ??? such that
>
> 	{f,g} ??? {a,b,c}
>
> 	-> {{f[a],g[a]},{f[b],g[b]},{f[c],g[c]}}
>
> you might be asking what's so difficult about the "@#,@#,... & /@"
> syntax, but what about when you don't have two functions f,g but 8-10
> functions... the syntax gets ugly fast and hard to read.
>
> note that
>
> 	Outer[{f, g}, {a, b, c}]
>
> 	-> {{f, g}[a], {f, g}[b], {f, g}[c]}
>
> doesn't work, neither does
>
> 	Outer[Apply, {f, g}, {a, b, c}]
>
> 	->{{a, b, c},{a, b, c}}
>
>
> thanks,
> Mitch
>
>
>
>



-- 
DrMajorBob at bigfoot.com


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