Re: Giving several functions the same argument

• To: mathgroup at smc.vnet.net
• Subject: [mg109609] Re: Giving several functions the same argument
• From: Bob Hanlon <hanlonr at cox.net>
• Date: Sat, 8 May 2010 07:06:00 -0400 (EDT)

```#[x] & /@ {Sin, Cos}

{sin(x),cos(x)}

{Sin[#], Cos[#]} &[x]

{sin(x),cos(x)}

Through[{Sin[#] &, Cos[#] &}[x]]

{sin(x),cos(x)}

% == %% == %%%

True

Bob Hanlon

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

In[2]:= functs[x]

Out[2]= {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[3]:= Table[functs[[i]][x], {i, 1, 2}]

Out[3]= {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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