Re: Execute and Call_function of complex things

[dirk(at)uwast.astro.wisc.edu (Dirk Fabian)]

... Sorry that didn't post.

Ok, once again.  This goes in the "why doesn't it work like i think it 
should" category.

Suppose I have an expression which, for the sake of argument, looks 
something like: 

exp((-1.)*(0.0 + Gauss1(x,p(0:2)) + Gauss1(x,p(3:5))))

where gauss1 is another function (of x) and p is a set of input 
parameters.

I want to evaluate this function, but can't seem to do it with either 
call_function or execute.  I've tried:

model='exp((-1.)*(0.0 + Gauss1(x,p(0:2)) + Gauss1(x,p(3:5))))'
result=call_function(model,p)

and 
expstring='model=exp((-1.)*(0.0 + Gauss1(x,p(0:2)) + Gauss1(x,p(3:5))))' 
result=call_function(expstring,p)

to no effect...  What am i missing about call_function or execute? Do all 
the elements of the evaluated function need to be IDL native?  Does the 
conversion of a string to a function make anyone else uneasy?

Thanks for any help! - Dirk