Re: evaluate f[{x,y,z}] when f[x,y,z] defined
- To: mathgroup at smc.vnet.net
- Subject: [mg103410] Re: [mg103383] evaluate f[{x,y,z}] when f[x,y,z] defined
- From: Murray Eisenberg <murray at math.umass.edu>
- Date: Sun, 20 Sep 2009 06:24:45 -0400 (EDT)
- Organization: Mathematics & Statistics, Univ. of Mass./Amherst
- References: <200909190926.FAA22303@smc.vnet.net> <1253355696.5955.0.camel@localhost>
- Reply-to: murray at math.umass.edu
Of course! (I was trying f[Sequence[a]] .) Thanks.
Patrick Scheibe wrote:
> Hi,
>
> just replace the List head of {1,2,3} by Sequence head.
>
> f[x_, y_, z_] := Sqrt[x^2 + y^2 + z^2];
> a = {1, 2, 3};
> f[Sequence @@ a]
>
>
> Cheers
> Patrick
>
> On Sat, 2009-09-19 at 05:26 -0400, Murray Eisenberg wrote:
>> 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
- References:
- evaluate f[{x,y,z}] when f[x,y,z] defined
- From: Murray Eisenberg <murray@math.umass.edu>
- evaluate f[{x,y,z}] when f[x,y,z] defined