On Sat, Oct 21, 2006 at 11:04:13AM +0200, Patrick Giraudoux wrote: > Which means that actually sum(x) is NOT considered equal to 1... > > Any idea about what is going wrong?
Others have already pointed out the problem and I would like to add a reference to a classical paper on this topic: David Goldberg What Every Computer Scientist Should Know About Floating-Point Arithmetic Computing Surveys, 1991 Reprints can be found in many places online - e.g. here: http://www.physics.ohio-state.edu/~dws/grouplinks/floating_point_math.pdf cu Philipp -- Dr. Philipp Pagel Tel. +49-8161-71 2131 Dept. of Genome Oriented Bioinformatics Fax. +49-8161-71 2186 Technical University of Munich Science Center Weihenstephan 85350 Freising, Germany and Institute for Bioinformatics / MIPS Tel. +49-89-3187 3675 GSF - National Research Center Fax. +49-89-3187 3585 for Environment and Health Ingolstädter Landstrasse 1 85764 Neuherberg, Germany http://mips.gsf.de/staff/pagel ______________________________________________ R-help@stat.math.ethz.ch 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.