[Rd] Inconsistent behaviour in solve (PR#805)
Wed, 10 Jan 2001 11:19:14 +0000 (GMT)
On Wed, 10 Jan 2001 email@example.com wrote:
> On Wed, 10 Jan 2001, Jonathan Rougier wrote:
> > What was puzzling was that the answers were not the same. The two results
> > will have different effects in further calculations as NaN and -Inf are
> > not treated identically (e.g. max or min). My understanding, supported by
> > the documentation, is that the two results should be identical, excepting
> > numerical accuracy.
> Really? Which documentation? I don't think they are the same once
> non-finite numbers are involved, and ?solve did not lead me to believe
I think it is by ommision. There is nothing in the solve documentation
that suggests that solve(A) %*% b and solve(A, b) will give different
answers if b contains non-finite values. Therefore it is reasonable to
expect the answers to be the same. May I suggest that a note might be
added to the documentation to highlight this?
Jonathan Rougier Science Laboratories
Department of Mathematical Sciences South Road
University of Durham Durham DH1 3LE
tel: +44 (0)191 374 2361, fax: +44 (0)191 374 7388
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