[Date Index] [Thread Index] [Author Index]

multiple outputs from a function

• To: mathgroup at smc.vnet.net
• Subject: [mg52753] multiple outputs from a function
• From: Ben Barrowes <barrowes at alum.mit.edu>
• Date: Sat, 11 Dec 2004 05:22:57 -0500 (EST)
• Sender: owner-wri-mathgroup at wolfram.com

I feel I must be missing something fundamental...

How do you write a function (or ?) in Mathematica which produces more 
than one output?

Let's say I have some data and I want a single function to calculate the 
mean, variance, std, etc, more than one thing and return those? I know 
that there are builtin functions for those parameters, but the point is 
I want to define functions with more than one output.

The only examples I can find are along the lines of:

f[x_,y_]:=x^2+y^2;

which have only a single result.

Is there a different structure altogether, such as a Subroutine, which 
allows multiple results from a single subunit?

One thought I had was that because Mathematica treats everything as 
global unless defined specifically local (e.g. in a module), that 
variables used in a procedure would be accessible and would thus be a 
"result", but it seems scoping problems would arise if this was used too 
often. For example:

In[67]:=
t1[x_,y_]:=(a1=x^2+y;a2=x+y^2;x+y)

In[68]:=
t2=t1[5,6]

Out[68]=
11

In[69]:=
a1

Out[69]=
31

In[70]:=
a2

Out[70]=
41

Is this the accepted method for extracting multiple results from one 
function definition?


Ben Barrowes

• Follow-Ups:
  • Re: multiple outputs from a function
    • From: DrBob <drbob@bigfoot.com>
  • Re: multiple outputs from a function
    • From: yehuda ben-shimol <benshimo@bgu.ac.il>
  • Re: multiple outputs from a function
    • From: Ben Kovitz <bkovitz@acm.org>