From owner-help-octave at bevo dot che dot wisc dot edu  Tue Oct 29 12:44:02 1996
Subject: eval and feval for reusable functions
From: John Utz <spaz at u dot washington dot edu>
To: Bernt Nilsson <berntn at sto dot foa dot se>
cc: "help-octave at bevo dot che dot wisc dot edu" <help-octave@bevo.che.wisc.edu>
Date: Tue, 29 Oct 1996 10:43:49 -0800 (PST)

Hello;

 On Tue, 29 Oct 1996, Bernt Nilsson wrote:

> Hello all,
> 
> Is there a way to send parameters to FSOLVE like there is in MATLAB (i.e. 
> fsolve('func',...,p1,p2,p3...))?
> 

Umm, this is not as specific an answer as i would like to give, but is has
been about a year since i last had to do this and i dont have any examples
in front of me...

	the technique for making functions that take arguments requires
using the eval() command. Unfortuneately, the help eval entry is
profoundly terse :-) :

*octave:1> help eval
* eval is a builtin function

*eval (TRY, CATCH)

*Evaluate the string TRY as octave code.  If that fails, evaluate the
*string CATCH.

but help -i eval brings up a really good discussion of how to use eval and
feval.

generally, one passes in a string or two, parses same using the octave
string commands and evals or fevals the resultant bits.

there is a bit of overhead in figuring out how to do this the first
time, but once one gets the hang of it it is a great facilitator of
reusable code.

> Bernt J Nilsson                               email : berntn at sto dot foa dot se
> FOA, Inst. 65                                   tel :    +46 8 706 3611
> S-172 90 Stockholm, Sweden                      FAX :    +46 8 706 3543

good luck!

*******************************************************************************
 John Utz	spaz at u dot washington dot edu
	idiocy is the impulse function in the convolution of life