Segmentation fault in subscripting array of lists (PR#904)
R clearly shouldn't crash, but tmp[[1, ]] is semantically incorrect. The result of "[[" is required to be a single value from a vector (or generally, an array) of the mode of the vector. To select more than one element from an array, you must use "[". The results from S-PLUS 6 are:
tmp[[1, ]]
Problem in [[: Attempt to select more than one element: structure(list(NULL, NULL, NULL, list(fred = c(1, 2, 3, 4, 5, 6, 7, 8, 9, 10)), NULL, NUL.... Use traceback() to see the call stack This error message indicates the error. Using "[" gives the correct result:
tmp[1, ]
[[1]]: NULL [[2]]: [[2]]$fred: [1] 1 2 3 4 5 6 7 8 9 10 [[3]]: NULL [[4]]: NULL # David Smith -- David M Smith <dsmith@insightful.com> S-PLUS Product Marketing Manager, Insightful Corp, Seattle WA Tel: +1 (206) 283 8802 x360 Fax: +1 (206) 283 0347 MathSoft is now Insightful! See www.insightful.com for details.
-----Original Message----- From: owner-r-devel@stat.math.ethz.ch [mailto:owner-r-devel@stat.math.ethz.ch]On Behalf Of J.C.Rougier@durham.ac.uk Sent: Tuesday, April 10, 2001 07:02 To: r-devel@stat.math.ethz.ch Cc: R-bugs@biostat.ku.dk Subject: [Rd] Segmentation fault in subscripting array of lists (PR#904) I get a segmentation fault as follows:
tmp <- array(list(), c(3, 4)) tmp[[1, 2]]
NULL # as expected
tmp[[1, 2]]$fred <- 1:10 tmp # as expected
[,1] [,2] [,3] [,4] [1,] "NULL" "List,1" "NULL" "NULL" [2,] "NULL" "NULL" "NULL" "NULL" [3,] "NULL" "NULL" "NULL" "NULL"
tmp[[1, 2]] # as expected
$fred [1] 1 2 3 4 5 6 7 8 9 10
tmp[[1, ]] # whoops!
Segmentation fault Cheers, Jonathan. --please do not edit the information below-- Version: platform = sparc-sun-solaris2.7 arch = sparc os = solaris2.7 system = sparc, solaris2.7 status = major = 1 minor = 2.1 year = 2001 month = 01 day = 15 language = R Search Path: .GlobalEnv, Autoloads, package:base -.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-. -.-.-.-.-.-.- r-devel mailing list -- Read http://www.ci.tuwien.ac.at/~hornik/R/R-FAQ.html Send "info", "help", or "[un]subscribe" (in the "body", not the subject !) To: r-devel-request@stat.math.ethz.ch _._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._. _._._._._._._
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