Thanks a lot, both of you. Incidentally, I made R crash when I forgot the X argument to strapply,
library(gsubfn) Loading required package: tcltk Loading Tcl/Tk interface ... done strapply("test", as.numeric) *** caught bus error *** address 0x13c, cause 'non-existent physical address' Traceback: 1: .External("dotTclcallback", ..., PACKAGE = "tcltk") 2: .Tcl.callback(x, e) 3: makeAtomicCallback(x, e) 4: makeCallback(get("value", envir = ref), get("envir", envir = ref)) 5: FUN(X[[3L]], ...) 6: lapply(val, val2obj) 7: .Tcl.args.objv(...) 8: structure(.External("dotTclObjv", objv, PACKAGE = "tcltk"), class = "tclObj") 9: .Tcl.objv(.Tcl.args.objv(...)) 10: tcl("set", "e", e) 11: strapply1(x, pattern, backref, ignore.case) 12: FUN("test"[[1L]], ...) 13: lapply(X, FUN, ...) 14: sapply(X, ff, simplify = is.logical(simplify) && simplify, USE.NAMES = USE.NAMES) 15: strapply("test", as.numeric) Possible actions: 1: abort (with core dump, if enabled) 2: normal R exit 3: exit R without saving workspace 4: exit R saving workspace sessionInfo() R version 2.10.0 (2009-10-26) i386-apple-darwin9.8.0 locale: [1] en_GB.UTF-8/en_GB.UTF-8/C/C/en_GB.UTF-8/en_GB.UTF-8 attached base packages: [1] stats graphics grDevices utils datasets grid methods [8] base other attached packages: [1] ggplot2_0.8.3 reshape_0.8.3 plyr_0.1.9 proto_0.3-8 fortunes_1.3-6 2009/11/18 Gabor Grothendieck <ggrothendi...@gmail.com>: > A minor variant might be the following: > > library(gsubfn) > strapply(input, "\\d+\\.\\d+E[-+]?\\d+", as.numeric, simplify = rbind) > > where: > > - as.numeric is used in place of c in which case we do not need combine > - \\d+ matches one or more digits > - \\. matches a decimal point > - [-+]? matches -, + or nothing (i.e. an optional sign). > - parentheses around the regular expression not needed > > On Wed, Nov 18, 2009 at 7:28 AM, Henrique Dallazuanna <www...@gmail.com> > wrote: >> Try this: >> >> strapply(input, "([0-9]+\\.[0-9]+E-[0-9]+)", c, simplify = rbind, >> combine = as.numeric) >> >> On Wed, Nov 18, 2009 at 9:57 AM, baptiste auguie >> <baptiste.aug...@googlemail.com> wrote: >>> Dear list, >>> >>> I'm seeking advice to extract some numeric values from a log file >>> created by an external program. Consider the following example, >>> >>> input <- >>> readLines(textConnection( >>> "some text >>> <ax> = 1.3770E-03 <bx> = 3.4644E-07 >>> <ay> = 1.9412E-04 <by> = 4.8840E-08 >>> >>> other text >>> <aax> = 1.3770E-03 <bbx> = 3.4644E-07 >>> <aay> = 1.9412E-04 <bby> = 4.8840E-08")) >>> >>> ## this is what I want >>> results <- c(as.numeric(strsplit(grep("<ax>", input,val=T), " ")[[1]][8]), >>> as.numeric(strsplit(grep("<ay>", input,val=T), " ")[[1]][8]), >>> as.numeric(strsplit(grep("<aax>", input,val=T), " ")[[1]][9]), >>> as.numeric(strsplit(grep("<aay>", input,val=T), " ")[[1]][9]) >>> ) >>> >>> ## [1] 0.00137700 0.00019412 0.00137700 0.00019412 >>> >>> The use of strsplit is not ideal here as there is a different number >>> of space characters in the lines containing <ax> and <aax> for >>> instance (hence the indices 8 and 9 respectively). >>> >>> I tried to use gsubfn for a cleaner construct, >>> >>> strapply(input, "<ax> += +([0-9.]+)", c, simplify=rbind,combine=as.numeric) >>> >>> but I can't seem to find the correct regular expression to deal with >>> the exponent. >>> >>> >>> Any tips are welcome! >>> >>> >>> Best regards, >>> >>> baptiste >>> >>> ______________________________________________ >>> 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. >>> >> >> >> >> -- >> Henrique Dallazuanna >> Curitiba-Paraná-Brasil >> 25° 25' 40" S 49° 16' 22" O >> >> ______________________________________________ >> 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.