A couple of week back someone posted this. It applies to you too: None of the people reading this at the moment can do this for you. Read the information on the page where you subscribed.:
https://stat.ethz.ch/mailman/listinfo/r-help Q: How many psychiatrists does it take to unscrew a light bulb? A: Only one, but the lightbulb must truly want to become unscrewed. On Sun, Dec 20, 2009 at 9:00 PM, lippel anna <lippelann...@hotmail.com>wrote: > > > > > Date: Mon, 21 Dec 2009 12:33:26 +1100 > > From: a.kowalew...@ugrad.unimelb.edu.au > > To: r-help@r-project.org > > Subject: [R] Limit on number of times Realloc can be called? > > > > Hello, > > > > I've been writing a program in C that will be called by R. I seem to have > > stumbled upon an odd error that seems to suggest there is a limit on the > > number of times "Realloc" (the R version as defined in the manual > > "R-extenstions" not the C version "realloc") when I try to use the > > following program: > > > > #include <R.h> > > #include <Rinternals.h> > > > > SEXP test_mem_alloc(SEXP z) { > > double *t = Calloc(sizeof(double), double); > > *t = 2; > > SEXP end_product; > > int i = 0; > > for(i=1; i < 20; i++) { > > t = Realloc(t, sizeof(t) + sizeof(double), double); > > t[i] = i; > > } > > PROTECT(end_product = allocVector(REALSXP,6)); > > for(i = 0; i < 20; i++) { > > REAL(end_product)[i] = t[i]; > > } > > UNPROTECT(1); > > Free(t); > > return end_product; > > } > > > > I call it from R using the following script: > > > > z <- 1 > > > > test_mem_alloc <- function(z) { > > if(!(is.loaded("test_mem_alloc_v6"))) > dyn.load("test_mem_alloc_v6.dll") > > out <- .Call("test_mem_alloc", > > as.double(z)) > > return(out) > > dyn.unload("test_mem_alloc_v6.dll") > > } > > > > Basically I get the following error messages: > > > > First: > > > > "Runtime Error! > > > > Program: C:\Program Files\R\R-2.10.0\bin\Rgui.exe > > > > This application has requested the Runtime to terminate it in an unusual > > way. Please contact the application's support team for more information." > > > > The second error message is: > > > > "The instruction at "0x0000002c". The memory could not be "read"." > > > > Now, if change the number of times the program goes through the for loop > > from 20 to say 6, and hence calls Realloc fewer times, then the program > > runs without any problems. It does not seem to have anything to do with > > the size of the memory being allocated as I changed the size of the total > > memory being allocated with a "for" loop with only 6 iterations to > > something that is substantially larger than the memory being allocated in > > the "for" loop when calling Realloc twenty times and the program ran > > successfully. Has anyone else come across this problem or knows about > some > > sort of limitation on using "Realloc" that is not specified in the R > > documentation? > > > > Any help would be greatly appreciated. > > > > Yours sincerely > > > > Adam Kowalewski > > > > ______________________________________________ > > 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<http://www.r-project.org/posting-guide.html> > > and provide commented, minimal, self-contained, reproducible code. > > _________________________________________________________________ > > ail you. > > cial-network-basics.aspx?ocid=PID23461::T:WLMTAGL:ON:WL:en-xm:SI_SB_3:092 > [[alternative HTML version deleted]] > > ______________________________________________ > 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<http://www.r-project.org/posting-guide.html> > and provide commented, minimal, self-contained, reproducible code. > [[alternative HTML version deleted]] ______________________________________________ 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.
