IEEE floating point provides a "double-extended" type often called a long double. The exact size of a double-extended can vary but the minimum specified by the spec is 80 bits. A PC with the IEEE extended type gives an approximate range from 3.4E-4932 to 1.1E4932, which would give you the range you want. Other architectures, such as a Tru64 alpha, give an even larger extended.
Reference: See the "IEEE Standard" in "What Every Computer Scientist Should Know About Floating-Point Arithmetic" http://docs.sun.com/source/806-3568/ncg_goldberg.html The "note" under R's ?numeric help says "All real numbers are stored in double precision format," so R apparently does not yet support the extended type. str(.Machine) in R gives a sizeof.longdouble, but I don't know how to use such a longdouble in native R -- perhaps someone else could enlighten us. C or C++ (or other languges) would support the long double type and the computations you'd like to do. efg Earl F. Glynn Stowers Institute for Medical Research ========= "Sebastian Kaiser" <[EMAIL PROTECTED]> wrote in message news:[EMAIL PROTECTED] Hello Everybody in order to get some needed results out of my function i need to get my besselI function evaluated at some values which normally gave Inf or 0 (expon.scaled NAN) back. So I would like to increase the range in R from approxamittly 1e+320 to aabout 1e+500 or something like that. Is there any possibility or pacckage to do this easily? Thank You Sebastian Kaiser Institut for Statistics in Munich Germany ______________________________________________ [EMAIL PROTECTED] mailing list https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide! http://www.R-project.org/posting-guide.html
