I see. I did not get these performances since did not directly compare arrays but run seemingly expensive for-loops to do it iteratively... :(
R. On Tue, Jul 13, 2010 at 1:42 AM, Hadley Wickham <had...@rice.edu> wrote: > strings <- replicate(1e5, paste(sample(letters, 100, rep = T), collapse = > "")) > system.time(strings[-1] == strings[-1e5]) > # user system elapsed > # 0.016 0.000 0.017 > > So it takes ~1/100 of a second to do ~100,000 string comparisons. You > need to provide a reproducible example that illustrates why you think > string comparisons are slow. > > Hadley > > > On Tue, Jul 13, 2010 at 6:52 AM, Ralf B <ralf.bie...@gmail.com> wrote: >> I am asking this question because String comparison in R seems to be >> awfully slow (based on profiling results) and I wonder if perhaps '==' >> alone is not the best one can do. I did not ask for anything >> particular and I don't think I need to provide a self-contained source >> example for the question. So, to re-phrase my question, are there more >> (runtime) effective ways to find out if two strings (about 100-150 >> characters long) are equal? >> >> Ralf >> >> >> >> >> >> >> On Sun, Jul 11, 2010 at 2:37 PM, Sharpie <ch...@sharpsteen.net> wrote: >>> >>> >>> Ralf B wrote: >>>> >>>> What is the fastest way to compare two strings in R? >>>> >>>> Ralf >>>> >>> >>> Which way is not fast enough? >>> >>> In other words, are you asking this question because profiling showed one of >>> R's string comparison operations is causing a massive bottleneck in your >>> code? If so, which one and how are you using it? >>> >>> -Charlie >>> >>> ----- >>> Charlie Sharpsteen >>> Undergraduate-- Environmental Resources Engineering >>> Humboldt State University >>> -- >>> View this message in context: >>> http://r.789695.n4.nabble.com/Fast-string-comparison-tp2285156p2285409.html >>> Sent from the R help mailing list archive at Nabble.com. >>> >>> ______________________________________________ >>> 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. >>> >> >> ______________________________________________ >> 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. >> > > > > -- > Assistant Professor / Dobelman Family Junior Chair > Department of Statistics / Rice University > http://had.co.nz/ > ______________________________________________ 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.