Re: Map[] and multiple args function
- To: mathgroup at smc.vnet.net
- Subject: [mg96228] Re: [mg96198] Map[] and multiple args function
- From: "David Park" <djmpark at comcast.net>
- Date: Tue, 10 Feb 2009 05:47:14 -0500 (EST)
- References: <20738936.1234177212952.JavaMail.root@m02>
You could do something like the following:
Foo[x_, y_, z_] := x + 2*y + 3*z
list = {{1, 2, 3}, {4, 5, 6}};
Total@(Foo @@ # & /@ list)
46
Plus @@ (Foo @@ # & /@ list)
46
David Park
djmpark at comcast.net
http://home.comcast.net/~djmpark/
From: sagrailo at gmail.com [mailto:sagrailo at gmail.com]
I know this has to be FAQ, but I'm just not able to find an answer
anywhere, so - here it goes: I have a multiple-arguments function,
say something like:
Foo[x_, y_, z_] := x + 2*y + 3*z
Now, I want to call this function number of times, over different sets
of arguments, and then to sum results. I thought about storing
argument triplets into some kind of list, and then employing sequence
of Map[] and Apply[] to get the job done. After number of trials and
errors, I came up with following piece of code doing the thing:
Plus @@ Foo /@ {{1, 2, 3}, {4, 5, 6}} /. List -> Sequence
but I even don't fully understand what's going here, and also I'm
wondering is there a "better" way to accomplish this. So - any
suggestion?
Thanks.