14 Sep 2000 10:43:05 -0700
>>>>> "SD" == Saikat DebRoy <firstname.lastname@example.org> writes:
>>>>> "AJR" == A J Rossini <email@example.com> writes:
>>>>> "MM" == Martin Maechler <firstname.lastname@example.org> writes:
MM> 2) For Computer Scientists : "Differentiation" / Symbolic
MM> Improve the possibilities of D() and deriv(), and document
MM> them. Make these user-extensible.
MM> Think about the hessian in addition to the gradient.
AJR> Even automating/specifications for numerical derivatives
AJR> would be nice.
SD> The nls package has a function called numericDeriv - with a
SD> little modification it could be used elsewhere. An earlier
SD> version of the underlying C code is used as an example in the
SD> R Extensions manual.
Right, and it would be nice (necessary?) for testing and verification
of the "symbolic" side of the package as well as for "drop-in" or
"change a parameter" design functionality. As well as being a
starting point for the interface for the symbolicDeriv package.
A.J. Rossini Rsrch. Asst. Prof. of Biostatistics
BlindGlobe Networks (home/default) email@example.com
UW Biostat/Center for AIDS Research firstname.lastname@example.org
FHCRC/SCHARP/HIV Vaccine Trials Net email@example.com
FHCRC: M/Tu: 206-667-7025 (fax=4812) | Voicemail is pretty sketchy
CFAR: W/F: 206-731-3647 (fax=3694) | Email is far better than phone
UW: Th/F: 206-543-1044 (fax=3286) | Change last 4 digits of phone for fax
r-devel mailing list -- Read http://www.ci.tuwien.ac.at/~hornik/R/R-FAQ.html
Send "info", "help", or "[un]subscribe"
(in the "body", not the subject !) To: firstname.lastname@example.org