Each of the following calls crash ("core dumps") R (R --vanilla) on
various versions and OSes:
regexpr("a{2-}", "")
sub("a{2-}", "")
gsub("a{2-}", "")
EXAMPLES:
> sessionInfo()
R version 2.11.1 Patched (2010-09-16 r52949)
Platform: i386-pc-mingw32 (32-bit)
...> regexpr("a{2-}", "")
Assertion failed: iter->max == -1 || iter->max == 1, file
tre-compile.c, line 1825
This application has requested the Runtime to terminate it in an unusual way.
Please contact the application's support team for more information.
> sessionInfo()
R version 2.12.0 Under development (unstable) (2010-09-14 r52910)
Platform: i386-pc-mingw32/i386 (32-bit)
...> regexpr("a{2-}", "")
Assertion failed: iter->max == -1 || iter->max == 1, file
tre-compile.c, line 1825
This application has requested the Runtime to terminate it in an unusual way.
Please contact the application's support team for more information.
> sessionInfo()
R version 2.11.0 Patched (2010-05-09 r51960)
x86_64-unknown-linux-gnu
...> regexpr("a{2-}", "")
R: tre-compile.c:1825: tre_ast_to_tnfa: Assertion `iter->max == -1 ||
iter->max == 1' failed.
Aborted
/Henrik
On Sep 21, 2010, at 11:04 PM, Henrik Bengtsson wrote:> Each of the following calls crash ("core dumps") R (R --vanilla) on > various versions and OSes: > > regexpr("a{2-}", "") > sub("a{2-}", "") > gsub("a{2-}", "") > > > EXAMPLES: > >> sessionInfo() > R version 2.11.1 Patched (2010-09-16 r52949) > Platform: i386-pc-mingw32 (32-bit) > ... >> regexpr("a{2-}", "") > Assertion failed: iter->max == -1 || iter->max == 1, file > tre-compile.c, line 1825 > This application has requested the Runtime to terminate it in an > unusual way. > Please contact the application's support team for more information. > >> sessionInfo() > R version 2.12.0 Under development (unstable) (2010-09-14 r52910) > Platform: i386-pc-mingw32/i386 (32-bit) > ... >> regexpr("a{2-}", "") > Assertion failed: iter->max == -1 || iter->max == 1, file > tre-compile.c, line 1825 > This application has requested the Runtime to terminate it in an > unusual way. > Please contact the application's support team for more information. > > >> sessionInfo() > R version 2.11.0 Patched (2010-05-09 r51960) > x86_64-unknown-linux-gnu > ... >> regexpr("a{2-}", "") > R: tre-compile.c:1825: tre_ast_to_tnfa: Assertion `iter->max == -1 || > iter->max == 1' failed. > AbortedNot a problem in reasonably current Mac with 64bit GUI: > regexpr("a{2-}", "") [1] 1 attr(,"match.length") [1] 0 > sub("a{2-}", "") Error in is.character(x) : 'x' is missing > gsub("a{2-}", "") Error in is.character(x) : 'x' is missing R version 2.11.1 Patched (2010-08-26 r52822) Platform: x86_64-apple-darwin9.8.0/x86_64 (64-bit) [R.app GUI 1.35 (5612) x86_64-apple-darwin9.8.0] -- David.> > > /Henrik > > ______________________________________________ > R-devel at r-project.org mailing list > https://stat.ethz.ch/mailman/listinfo/r-devel
I have recently become aware of some curious behaviour of median() which I think could be usefully corrected. I am sure this must have come up before, but I'm raising it again. The phenomenon is best shown by a simple example.> d <- matrix(runif(4*4), 4, 4) > d[,1] [,2] [,3] [,4] [1,] 0.1388592 0.08478220 0.02012404 0.7733054 [2,] 0.1718332 0.06370432 0.66167219 0.2521809 [3,] 0.3190116 0.08616569 0.23107320 0.6278422 [4,] 0.9185233 0.29218144 0.99193823 0.6306847> apply(d, 1, median)[1] 0.1118207 0.2120070 0.2750424 0.7746040 So far, so good. But what happens when you turn it into a data frame?> d <- data.frame(d) > apply(d, 1, median)[1] 0.1118207 0.2120070 0.2750424 0.7746040 No problem there, yet. But if you just look at one row:> median(d[1, ])[1] 0.0847822 0.1388592 without warning you get a vector of size two as the result, viz the two values which enclose the middle. I thought this was simply because one row of a data frame is a list, but that can't be the whole story. e.g.> median(d[,1])[1] 0.2454224> median(as.list(d[,1]))Error in sort.list(x, partial = half + 0L:1L) : 'x' must be atomic for 'sort.list' Have you called 'sort' on a list?>(Well yes, Brian, I did...) The function mean() has a nice property when you call it on a data frame, e.g.> mean(d)X1 X2 X3 X4 0.3870568 0.1317084 0.4762019 0.5710033 and just to complicate the issue even further,> mean(d[1, ])X1 X2 X3 X4 0.13885916 0.08478220 0.02012404 0.77330535 On the other hand, median(), whose behaviour should be similar I would suggest, just fails when handed a data frame argument.> median(d)[1] NA NA Warning messages: 1: In mean.default(X[[1L]], ...) : argument is not numeric or logical: returning NA 2: In mean.default(X[[2L]], ...) : argument is not numeric or logical: returning NA>_________________ I suggest that there should be some consistency here, and I suggest that median() be given a data.frame method that would allow it to respond much the same as mean() does. The way it responds to data frame arguments now is quirky, at best. Currently median() though generic, has only the default method.> methods("mean")[1] mean.data.frame mean.Date mean.default mean.difftime mean.POSIXct [6] mean.POSIXlt> methods("median")[1] median.default>Perhaps quantile() should also have a data.frame method for the same reason. To me it seems curious, too, that quantile has a POSIXt method (in the stats package) whereas median currently does not. (mean.POSIX*t are in the base package.)> methods("quantile")[1] quantile.default quantile.POSIXt* Non-visible functions are asterisked>How do people respond to this? (I see there have been hints of this in the past, see http://tolstoy.newcastle.edu.au/R/e2/help/06/12/7692.html but I could only find hints.) Bill Venables CSIRO/CMIS, Cleveland Labs.
On 9/21/2010 8:04 PM, Henrik Bengtsson wrote:> Each of the following calls crash ("core dumps") R (R --vanilla) on > various versions and OSes: > > regexpr("a{2-}", "") > sub("a{2-}", "") > gsub("a{2-}", "") > > > EXAMPLES:To add another (windows) example it also crashes the 2.12.0 alpha build: > sessionInfo() R version 2.12.0 alpha (2010-09-20 r52948) Platform: i386-pc-mingw32/i386 (32-bit) ... > regexpr("a{2-}", "") Assertion failed: iter->max == -1 || iter->max == 1, file tre-compile.c, line 1825 This application has requested the Runtime to terminate it in an unusual way. Please contact the application's support team for more information.>> sessionInfo() > R version 2.11.1 Patched (2010-09-16 r52949) > Platform: i386-pc-mingw32 (32-bit) > ... >> regexpr("a{2-}", "") > Assertion failed: iter->max == -1 || iter->max == 1, file > tre-compile.c, line 1825 > This application has requested the Runtime to terminate it in an unusual way. > Please contact the application's support team for more information. > >> sessionInfo() > R version 2.12.0 Under development (unstable) (2010-09-14 r52910) > Platform: i386-pc-mingw32/i386 (32-bit) > ... >> regexpr("a{2-}", "") > Assertion failed: iter->max == -1 || iter->max == 1, file > tre-compile.c, line 1825 > This application has requested the Runtime to terminate it in an unusual way. > Please contact the application's support team for more information. > > >> sessionInfo() > R version 2.11.0 Patched (2010-05-09 r51960) > x86_64-unknown-linux-gnu > ... >> regexpr("a{2-}", "") > R: tre-compile.c:1825: tre_ast_to_tnfa: Assertion `iter->max == -1 || > iter->max == 1' failed. > Aborted > > > /Henrik >-- Brian S. Diggs, PhD Senior Research Associate, Department of Surgery Oregon Health & Science University
[Accidentally posted this to r-help instead of r-devel; reposting to put it into the correct list and thread. My apologies for the duplication.] On 9/21/2010 8:04 PM, Henrik Bengtsson wrote:> Each of the following calls crash ("core dumps") R (R --vanilla) on > various versions and OSes: > > regexpr("a{2-}", "") > sub("a{2-}", "") > gsub("a{2-}", "") > > > EXAMPLES:To add another (windows) example it also crashes the 2.12.0 alpha build: > sessionInfo() R version 2.12.0 alpha (2010-09-20 r52948) Platform: i386-pc-mingw32/i386 (32-bit) ... > regexpr("a{2-}", "") Assertion failed: iter->max == -1 || iter->max == 1, file tre-compile.c, line 1825 This application has requested the Runtime to terminate it in an unusual way. Please contact the application's support team for more information.>> sessionInfo() > R version 2.11.1 Patched (2010-09-16 r52949) > Platform: i386-pc-mingw32 (32-bit) > ... >> regexpr("a{2-}", "") > Assertion failed: iter->max == -1 || iter->max == 1, file > tre-compile.c, line 1825 > This application has requested the Runtime to terminate it in an unusual way. > Please contact the application's support team for more information. > >> sessionInfo() > R version 2.12.0 Under development (unstable) (2010-09-14 r52910) > Platform: i386-pc-mingw32/i386 (32-bit) > ... >> regexpr("a{2-}", "") > Assertion failed: iter->max == -1 || iter->max == 1, file > tre-compile.c, line 1825 > This application has requested the Runtime to terminate it in an unusual way. > Please contact the application's support team for more information. > > >> sessionInfo() > R version 2.11.0 Patched (2010-05-09 r51960) > x86_64-unknown-linux-gnu > ... >> regexpr("a{2-}", "") > R: tre-compile.c:1825: tre_ast_to_tnfa: Assertion `iter->max == -1 || > iter->max == 1' failed. > Aborted > > > /Henrik >-- Brian S. Diggs, PhD Senior Research Associate, Department of Surgery Oregon Health & Science University