Re: laguerre.m functions in specfun package

[Colin Macdonald]

On 29/04/15 06:46, Juan Pablo Carbajal wrote:
> On Tue, Apr 28, 2015 at 6:30 PM, Carnë Draug <address@hidden> wrote:
> > I am arguing that dirac and heaviside should be moved to the symbolic
> > package.  And then we drop the specfun package.
> > See https://savannah.gnu.org/patch/?8644#comment13
>
> I completely disagree with this.
> Symbolic does not offer replacement for these functions. Specially it
> is not true that
>
> multinom, multinom_coeff, multinom_exp -- I think these are monomials,
> and nthcoeff in the sym,bolic package
>
> (mind the "I think"). These functions are optimized for numeric not
> for symbolic manipulation (which by the way is the main role of
> octave). The symbolic version of these function will just ad an over
> heard in time execution and memory!
>
> Please always think of this when you want to replace a numerical
> version of a function with a symbolic one (please!). You should
> provide performance (time and memory) justifying the change.

I develop Symbolic but I have no particular agenda here either way: so 
long as I can rely on users having some of these functions for doubles.

re: performance: *generally speaking* function with symbolic arguments 
call e.g., "@sym/dirac.m", whereas with double arrays they call e.g., 
"@double/dirac.m" so there should be no cpu/mem performance penalty for 
numerical computing.  I'm keen to ensure it stays that way.

> In any case, if you want to get rid of specfun (I do not know why you
> would want that!), I would say be mindful if your are not a user of
> the package. Your interest might not coincide with the interest of the
> true/intended users.