Jason Rupert
2010-Jun-13 23:23 UTC
[R] Best way to remove double precision round off chaff
I would like to get rid of the double precision round off chaff, so is the following the best way to handle it?> 0.625-0.8+0.45-0.275[1] -5.551115e-17> round(0.625-0.8+0.45-0.275, digits=4)[1] 0 Motivation for removing the chaff is for no other reason than to titty up the digits for display purposes and to help quicken the analysis of values that most definitely should be zero. Thanks for any insights and feedback.
Jason: Many print methods have specific options to control this: ?print.default See also the "digits" and "scipen" settings in ?options for global control (these can be put in your startup file, for example). See also ?format and e.g. ?sprintf for more precise control of print format. All of this has to do with what is displayed and does not change the underlying values, of course, which round() and friends do. Cheers, Bert Gunter Genentech Nonclinical Statistics -----Original Message----- From: r-help-bounces at r-project.org [mailto:r-help-bounces at r-project.org] On Behalf Of Jason Rupert Sent: Sunday, June 13, 2010 4:24 PM To: R Project Help Subject: [R] Best way to remove double precision round off chaff I would like to get rid of the double precision round off chaff, so is the following the best way to handle it?> 0.625-0.8+0.45-0.275[1] -5.551115e-17> round(0.625-0.8+0.45-0.275, digits=4)[1] 0 Motivation for removing the chaff is for no other reason than to titty up the digits for display purposes and to help quicken the analysis of values that most definitely should be zero. Thanks for any insights and feedback. ______________________________________________ R-help at 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.