Re: evaluate f[{x,y,z}] when f[x,y,z] defined
- To: mathgroup at smc.vnet.net
- Subject: [mg103402] Re: [mg103383] evaluate f[{x,y,z}] when f[x,y,z] defined
- From: "David Park" <djmpark at comcast.net>
- Date: Sun, 20 Sep 2009 06:22:45 -0400 (EDT)
- References: <1067475.1253352954604.JavaMail.root@n11>
f[x_, y_, z_] := Sqrt[x^2 + y^2 + z^2]
a = {4, 3, 2};
f @@ a
Sqrt[29]
But if it is something heavily used in both forms it might be worthwhile
making the extra definition.
David Park
djmpark at comcast.net
http://home.comcast.net/~djmpark/
From: Murray Eisenberg [mailto:murray at math.umass.edu]
I ought to know how to do this (simply) but don't, or at least don't
recall how...
Often I have a function of several variables defined, for example:
f[x_, y_, z_] := Sqrt[x^2 + y^2 + z^2]
And I have some list of numbers, e.g.:
a = {4, 3, 2};
How can I evaluate the following...
f[a]
... without having to make a separate definition such as
f[{x_, y_, z_}] := f[x, y,z]
?
--
Murray Eisenberg murray at math.umass.edu
Mathematics & Statistics Dept.
Lederle Graduate Research Tower phone 413 549-1020 (H)
University of Massachusetts 413 545-2859 (W)
710 North Pleasant Street fax 413 545-1801
Amherst, MA 01003-9305