I don't think so -- as I understand it, what David is looking for is a method for taking a specification for the general term in a series (of indefinite length) and accumulating the sum of terms until a convergence criterion is satisfied -- see his Mathematica-inspired hypothetical example (in his later mail):
x <- 2.232; sum(f = function(n) {x^n/factorial(n)}, lower = 0, upper = Inf, numeric.method = "HypergeometricTermZeilberger", verify.convergence = TRUE) Your "Reduce" example simply takes a fixed input vector of given finite length, and in fact is equivalent to sum(1/2^(1:10)) # [1] 0.9990234 The result he would want is 1.0000000 (to within some "tol=..."), from input "1/2^n" as an expression. I've not seen anything generic for this kind of thing in R; though one could fairly easily write a naive function to do it, modulo some head-scratching about how to test for convergence (an appropriate test would depend on what kind of series was being summed). Ted. On 15-Jul-10 08:21:59, Allan Engelhardt wrote: > Not 100% if this is what you are looking for, but maybe Reduce("+", x) > will do it? E.g. > > Reduce("+", 1/2^(1:10)) ># [1] 0.9990234 > > Hope this helps. > > Allan > > On 14/07/10 11:57, David Bickel wrote: >> What are some reliable R functions that can compute the value of a >> convergent series? >> >> David >> > > ______________________________________________ > R-help@r-project.org mailing list > https://stat.ethz.ch/mailman/listinfo/r-help > PLEASE do read the posting guide > http://www.R-project.org/posting-guide.html > and provide commented, minimal, self-contained, reproducible code. -------------------------------------------------------------------- E-Mail: (Ted Harding) <ted.hard...@manchester.ac.uk> Fax-to-email: +44 (0)870 094 0861 Date: 15-Jul-10 Time: 10:28:00 ------------------------------ XFMail ------------------------------ ______________________________________________ R-help@r-project.org mailing list https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide http://www.R-project.org/posting-guide.html and provide commented, minimal, self-contained, reproducible code.