Displaying 20 results from an estimated 20000 matches similar to: "Subsetting a vector in C"
2013 Apr 01
2
Timing of SET_VECTOR_ELT
Assume a C program invoked by .Call, that returns a list.
Near the top of the program we allocate space for all the list elements. (It is my habit
to use "xyz2" for the name of the R object and "xyz" for the pointer to its contents.)
PROTECT(means2 = allocVector(REALSXP, nvar));
means = REAL(means2);
PROTECT(u2 = allocVector(REALSXP, nvar));
u =
2006 Nov 17
1
Manipulating R lists in C
Hi,
I have been studying the R manual on lists but cannot seem to create a
simple R list in C - I keep on getting "'dimnames' applied to non-array"
whenever I attempt to assign names to the list elements:
Wanted output a list structure something like
[ type="Bid", price=2.0, volume=1000 ]
I can get up to a list of
[ "Bid2, 2.0, 1000 ]
But for the life of
2011 Jan 17
1
isoreg memory leak?
I believe there is a memory leak in isoreg in the current version of R,
as I believe the following shows
> gc()
used (Mb) gc trigger (Mb) max used (Mb)
Ncells 120405 3.3 350000 9.4 350000 9.4
Vcells 78639 0.6 786432 6.0 392463 3.0
> for(k in 1:100) {
+
+ y <- runif(10000)
+ isoreg(x,y)
+ }
> rm(x)
> rm(y)
> gc()
used (Mb) gc
2011 Oct 24
2
C function is wrong under Windows 7
Dear mailing list,
I have a C function that gives me a wrong result when I run it under Windows
7.
This is the code under Linux (RHEL5):
> library(phenoTest)
> data(epheno)
> sign <- sample(featureNames(epheno))[1:20]
> score <- getFc(epheno)[,1]
> head(score)
1007_s_at 1053_at 117_at 121_at 1255_g_at 1294_at
-1.183019 1.113544 1.186186 -1.034779 -1.044456
2018 Feb 02
1
R-gui sessions end when executing C-code
Hi
I'm trying to develop some C code to find the fixpoint of a contraction mapping, the code compiles and gives the right results when executed in R.
However R-gui session is frequently terminated. I'm suspecting some access violation error due to the exception code 0xc0000005
In the error report windows 10 gives me.
It is the first time I'm writing any C-code so I'm guessing I
2003 Nov 03
2
lang2(...) with two and more arguments
Dear R-help,
how could I create an R call in C code using lang2 with 2 and more
arguments? I tried this code:
SEXP f(SEXP fn, SEXP rho)
{
SEXP R_fcall, x, y;
PROTECT(R_fcall = lang2(fn, R_NilValue));
PROTECT(x = allocVector(REALSXP, 1));
PROTECT(y = allocVector(REALSXP, 1));
REAL(x)[0] = 10;
REAL(y)[0] = 20;
SETCADR(R_fcall, x);
SETCADR(R_fcall, y);
1997 May 12
1
R-alpha: Hypergeometric Distribution
A cut and paste typo has crept in and is rendering all values returned
for the hypergeometric distribution incorrect. The problem is in
src/main/arithmetic.c in the function "math4". The lines
PROTECT(sy = allocVector(REALSXP, n));
a = REAL(sa);
b = REAL(sb);
c = REAL(sc);
d = REAL(sc); /* <-- change this line */
y = REAL(sy);
should
2008 Apr 05
2
Adding a Matrix Exponentiation Operator
Hi all
I recently started to write a matrix exponentiation operator for R (by
adding a new operator definition to names.c, and adding the following code
to arrays.c). It is not finished yet, but I would like to solicit some
comments, as there are a few areas of R's internals that I am still feeling
my way around.
Firstly:
1) Would there be interest in adding a new operator %^% that performs
2013 Jul 13
2
missing PROTECT() in src/main/arithmetic.c
at lines 651 & 653 (integer_binary function):
if (code == DIVOP || code == POWOP)
ans = allocVector(REALSXP, n);
else
ans = allocVector(INTSXP, n);
There are calls to warningcall() later in the function, which can
trigger garbbage collection.
Looks like the typical scenario where it seemed pretty safe to not
PROTECT in the original version of the function but
2013 Apr 17
1
stack imbalance in max.col for non-real matrices
It's tough to reliably reproduce, but I often get stack imbalance warnings
when calling max.col() on non-real/double matrix. The code is conditionally
PROTECTing but not incrementing its nprot counter for the eventual
UNPROTECT. Pretty sure this would fix (but I haven't tested it):
Index: array.c
===================================================================
--- array.c (revision
2010 Sep 10
2
[xts, quantmod] segfault probelm when I work with memcpy function
Hi,
I work with SEXP C code and with xts and quantmod packages. I try to
touch how xts internal works.
So we have R session and:
> ls()
character(0)
> getSymbols('AAPL') # quantmod package
[1] "AAPL"
> ls()
[1] "AAPL"
> str(AAPL)
An ?xts? object from 2007-01-03 to 2010-09-09 containing:
Data: num [1:929, 1:6] 86.3 84 85.8 86 86.5 ...
- attr(*,
2014 Jun 26
1
using 2D array of SEXP for creating dataframe
Hi ,
For our production package i need to create a dataframein C . So I wrote
the following code
SEXP dfm ,head,df , dfint , dfStr,lsnm;
*SEXP valueVector[2];*
char *ab[3] = {"aa","vv","gy"};
int sn[3] ={99,89,12};
char *listnames[2] = {"int","string"};
int i,j;
//=============================
PROTECT(df = allocVector(VECSXP,2));
2001 Apr 09
1
syntax error in datetime.c (PR#901)
Full_Name: Naoki Takebayashi
Version: 1.2.2
OS: Linux, RedHat 7.0/alpha
Submission from: (NULL) (152.3.12.123)
With RedHat 7.0/alpha (gcc 2.96-69), I encountered following error:
gcc -I. -I../../src/include -I../../src/include -I/usr/local/include
-DHAVE_CONFIG_H -mieee -O2 -mieee -c datetime.c -o datetime.o
datetime.c: In function `do_systime':
datetime.c:306: parse error before `ans'
2007 Aug 23
1
.Call and to reclaim the memory by allocVector
Hi,
I am not sure if this is a bug and I apologize if it is something I
didn't read carefully in the R extension manual. My initial search on the
R help and R devel list archive didn't find useful information.
I am using .Call (as written in the R extension manual) for the C code
and have found that the .Call didn't release the memory claimed by
allocVector. Even after applying
2007 Aug 23
1
.Call and to reclaim the memory by allocVector
Hi,
I am not sure if this is a bug and I apologize if it is something I
didn't read carefully in the R extension manual. My initial search on the
R help and R devel list archive didn't find useful information.
I am using .Call (as written in the R extension manual) for the C code
and have found that the .Call didn't release the memory claimed by
allocVector. Even after applying
2011 Nov 17
3
.Call in R
Hi R developers,
I am new to this forum and hope someone can help me with .Call in R.
Greatly appreciate any help!
Say, I have a vector called "vecA" of length 10000, I generate a vector
called "vecR" with elements randomly generated from Uniform[0,1]. Both vecA
and vecR are of double type. I want to replace elements vecA by elements in
vecR only if sum of elements in
2004 Nov 12
1
dyn.load problem
Hi R-Users
I wrote 1 week ago asking about a message that appears when I try run
dyn.load.
I'm trying to do an example in C code from "Writing R Extension" to
learn how to do it.
I have R 2.0.0, Rtools, Perl and MinGW as describe in
http://www.murdoch-sutherland.com/Rtools/ with path sets.
When I use C:\R\rw2000\bin>RCMD SHLIB -o C:/dev-cpp/teste.dll
2006 Mar 27
1
Safe to UNPROTECT() when object is assigned to a list?
Hi,
I'm troubleshooting some native code on Windows that very occationally
(and semi-randomly) crashes R. Already looked at "everything", I just
want to double check that it is safe to UNPROTECT() allocated
variables as soon as they are assigned to, say, a PROTECTed list.
>From (R v2.3.0) Section 5.7.1 "Handling the effects of garbage
collection" in "Writing R
2010 Apr 14
2
Why no race condition when returning UNPROTECT-ed memory from C?
Consider the C (or C++) code called from the .Call interface:
SEXP foo() {
SEXP *p = PROTECT(allocVector(REALSXP, 10));
...
UNPROTECT(1);
return p;
}
Why is there no danger that the allocated memory will be garbage
collected after the UNPROTECT, but before the return of p?
I have used code like this for some time and have never had a
problem, but I'm not sure if/why it is guaranteed
2001 Mar 28
1
Help: Using R from C
Hi folks:
I am just beginning to try and use R from my own C programs. Platform is
Windows2000, compiler Visual C++ 6.0. I built the import library R.lib from
R.dll using the VC LIB.exe program. Here is a simple code I am trying to
compile and run (no C++, VC++ is instructed to treat it strictly as C):
#include "R.h"
#include "Rinternals.h"
int main(void)
{
int i;
char