August Washington wrote: > I meet a problem about my R code. I find the output of my R code is > different from the result several months ago. Do anybody meet this > situation and how to explain? >
Not me, the square root of 2 is pretty much the same it was last year. Possibilities, in the order I'd check them: 1. You're using pseudo random numbers. runif(10) today is not the same as runif(10) five minutes ago. Any analysis that uses random sampling will produce different output at some level. 2. You're running a different script to the one you thought you ran a month ago. Or with slightly different parameters. 3. You're using different data. A tiny change in input could mean a large change in output. Maybe this time you've not excluded some outliers? How detailed is your logging of what you did a month ago? (I have trouble remembering what I did yesterday, but then again that was New Year's Day so I have an excuse...). 4. You're using a different version of R or of a package. It might have had a bug fixed which means last month's answers were wrong and this month's answers are right. Or it could have had a bug introduced, which means last month's answers were right and this month's answers are wrong. Check these all out, and if you still get different answers... just take the average and call it a meta-analysis [joke]. Barry ______________________________________________ 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.
