This is the mail archive of the gsl-discuss@sources.redhat.com mailing list for the GSL project.


Index Nav: [Date Index] [Subject Index] [Author Index] [Thread Index]
Message Nav: [Date Prev] [Date Next] [Thread Prev] [Thread Next]
Other format: [Raw text]

Re: Mathieu functions ready for alpha testing


Lowell Johnson writes:
 > Mathieu function routines have been committed on the mathieu-1-4
 > CVS branch under the specfunc directory.  They presently handle the
 > angular functions and the radial functions of type 1, integer order
 > and real arguments only.  These limitations are based in part on
 > the current lack of support for complex arguments in the GSL Bessel
 > and Hankel function routines.  Also the highest order is currently
 > limited to 100.  I haven't spent much time testing the argument
 > limits.

Cool.   Good work.

I don't know much about these functions but here are some comments:

Clean compile with -Wall.  No memory problems noted by various testing
tools either.  Good.

According to the GSL Design document avoid using malloc inside the
functions, or returning a * pointer to malloced memory block. Instead
have a suitable array argument passed in by the caller.

Test values -- best practice would be to "fail-safe" here, by not
using the output of the function as an expected value.  Otherwise some
of the tests may slip through into a released version.

The ACM TOMS papers ought to discuss testing somewhere (I would hope)
http://math.nist.gov/toms/cgi-bin/TOMSsearch?string=mathieu

I also found  J. Phys. A: Math. Gen. 34 (2001) 3541­3551
http://www.cbpf.br/~portugal/Mathieu.pdf

For multi-precision calculations Maxima, GP-Pari and Emacs Calc are
good choices.


Index Nav: [Date Index] [Subject Index] [Author Index] [Thread Index]
Message Nav: [Date Prev] [Date Next] [Thread Prev] [Thread Next]