       Re: Giving several functions the same argument

• To: mathgroup at smc.vnet.net
• Subject: [mg109614] Re: Giving several functions the same argument
• From: Leonid Shifrin <lshifr at gmail.com>
• Date: Sat, 8 May 2010 07:06:54 -0400 (EDT)

```Hi Simon,

You are right, such a function does exist. Its name is  Through:

In:= functs = {Sin[#1] &, Cos[#1] &};

In:= Through[functs[x]]

Out= {Sin[x], Cos[x]}

Here is one more way to do this:

In:= Map[#[x] &, functs]

Out= {Sin[x], Cos[x]}

Regards,
Leonid

On Fri, May 7, 2010 at 2:28 PM, Simon Pearce
<Simon.Pearce at nottingham.ac.uk>wrote:

> Hi Mathgroup,
>
>
>
> I have a list of pure functions, which I wish to apply to the same
> argument. I can't seem to be able to thread the list of functions over
> the argument in a simple way, all the commands like Apply and Map etc
> take a single function. I can do it using Table and Part, but it seemed
> like there should be a simple command that I'm missing.
>
>
>
> For example:
>
>
>
> In:= functs = {Sin[#1] &, Cos[#1] &};
>
>
>
> In:= functs[x]
>
>
>
> Out= {Sin[#1] &, Cos[#1] &}[x]
>
>
>
> I want to get the result {Sin[x],Cos[x]} out, without having to use
> something of the form:
>
>
>
> In:= Table[functs[[i]][x], {i, 1, 2}]
>
>
>
> Out= {Sin[x], Cos[x]}
>
>
>
> Which seems like it'd be less efficient when I try and use it on long
> lists of functions.
>
>
>
> Thanks,
>
> Simon
>
>

```

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