similar to: More questions about R extension programming

Hi, I want to read a text file into R with .Call(). So I define some NEW_CHARACTER() to store the chracters read and use SET_STRING_ELT to fill the elements. e.g. PROTECT(qNames = NEW_CHARACTER(10000)); char *foo; // This foo holds the string I want. while(foo = readLine(FN)){ SET_STRING_ELT(qNames, i, mkChar(foo))); } In this way, I can get the desired character from qNames. The only problem

Can someone lend me a hand with extracting the dimnames from a SEXP? I've looked through R-exts, but I couldn't find an example. Here is the code I'm using to grab the jth column name and print it, but the colnames I'm getting are garbage. None of the following are working. void printInfo(SEXP ts) { int j; for (j=0; j<col; j++) {

Hi, I have a C code which produces array of integers and potentially a string, and I have problems passing the string out. Here is the relevant part of the code: 1 PROTECT(Ret = allocVector(INTSXP, n)); 2 ret = (int*) INTEGER(Ret); /* get pointer to R's Ret */ 3 for(i=0; i<n; i++) ret[i] = data[i]; 4 Free(data); 5 i=1; 6 if (comment) { // comment was found 7 n

Hi, I have a C code which produces array of integers and potentially a string, and I have problems passing the string out. Here is the relevant part of the code: 1 PROTECT(Ret = allocVector(INTSXP, n)); 2 ret = (int*) INTEGER(Ret); /* get pointer to R's Ret */ 3 for(i=0; i<n; i++) ret[i] = data[i]; 4 Free(data); 5 i=1; 6 if (comment) { // comment was found 7 n

I am writing bindings to the neural network simulator SNNS. At present I have used only .C interface, now I'm studying .Call interface. I have adapted the example from page 77 of r-exts.pdf, however, it crashes R. I use MingW as recommended by Duncan Murdoch. Please, tell me what I am missing. The code is below. Thank you. SEXP snns_getVersion(void) {SEXP version; char *v;

Hi Everyone, I have a problem using some working 32-bit R code with 64-bit machine ( I am using version R-2.4.1 ). The problem occurs when I am trying to detect a NULL STRSXP type. ( Perhaps I am doing this detection in the wrong way? ) On 32-bit the following works, and correctly identifies if I am passing NULL or a valid string object: if ( v_dta_start != R_NilValue && STRING_ELT(

Hi, It seems that new("externalptr") is always returning the same instance, and not a new one as one would expect from a call to new(). Of course this is hard to observe: > new("externalptr") <pointer: (nil)> > new("externalptr") <pointer: (nil)> since not a lot of details are displayed. For example, it's easy to see that 2

Hi, I am trying to study R internal behaviour. So long, I have not succeeded to access the value of R strings from C. I use: void salvesta_tabel( SEXP data_frame, SEXP file ) { printf( "nimi %d\n", (R_CHAR)( file)); } and from the R side: salvesta.tabel <- function (x, file = "") { .Call( "salvesta_tabel", x, file) } When calling

The other day I was working on an example which used tempfile() to create file for use by the graphics device. And while I love tempfile()---as it is portable and clever and the files get cleaned by R and all that---I noticed one missing feature I would like to see: beside a starting name pattern, and an optional directory, an 'file extension' argument would be nice to have. As e.g. in

Hi folks. I posted this question a few days ago, but maybe it got lost because of the code I included with it. I'm having a problem using the SET_LENGTH() macro in an R extension I'm writing in C++. In a function within the extension I use SET_LENGTH() to resize R vectors so as to allow the concatenation of single values onto the vectors -- it's a "push back" function to

For example, the following changes are necessary when i convert a Japanese hiragana into katakana in chattr. R code: > chartr("\u3041-\u3093","\u30a1-\u30f3","\u3084\u3063\u305f\u30fc") --- R-alpha.orig/src/main/character.c 2007-09-05 07:13:27.000000000 +0900 +++ R-alpha/src/main/character.c 2007-09-13 16:10:21.000000000 +0900 @@ -2041,6 +2041,16 @@

R community, As you may know, R's iconv doesn't work well converting to and from encodings that allow embedded nulls. For example > iconv("foo", to="UTF-16") Error in iconv("foo", to = "UTF-16") : embedded nul in string: '\xff\xfef\0o\0o\0' However, I don't believe embedded nulls are at issue here, but rather that R's iconv

Hello, I try to write an extension in C, to get a faster functions. Therefore I have to add an element (vector) to a vector. The command in R is very simple: x = c(x,a) But in C I have the problem to reallocate my vector for getting more space. Everything I tried, I get a "Segmentation fault". So, how can I combine two vectors in C and give the result back to R (return(x))? Thanks

Looking at shash in unique.c, from R-2.10.1 I'm wondering if it makes sense to hash the pointer itself rather than the string it points to? In other words could the SEXP pointer be cast to unsigned int and the usual scatter be called on that as if it were integer? shash would look like a slightly modified version of ihash like this : static int shash(SEXP x, int indx, HashData *d) {

Hi, I have an SEXP obj in a C function called via .Call(). The obj is protected (in fact it is an argument to .Call and therefore automatically protected). If I set an attribute of obj does the attribute become protected too? Here is an example SEXP foo(SEXP obj) { SET_NAMES(obj, NEW_CHARACTER(3)); /* are names protected or not? */ ... } Thanks, Vadim [[alternative HTML version

I'm trying to get a reference to this object in C SWX.RET[1:6,c("SBI,"SPI","SII")] While i am able to access and use a plain SWX.RET object, I'm getting confused on how to create an object with the array subscripts like above. Here is what I tried to do. It doesn't work because "[" is obviously not an operation or function on SWX.RET. So how do I

Hello: I was hoping to get some advice about how to return a tree (basically a linked list -- with each node containing a parent, left, and right node pointers) from a C routine back into R. Each node itself contains several attributes (a double, a char *, an int, and a void * ) Initially I was thinking I could just return to R a SEXP containing a pointer to the Root Node, but then realized

Hello, I'm trying to fetch a data frame through the C API, and have no problem doing this when all columns are numbers, but when there is a column of strings I have a problem. On the C-side the function looks like: SEXP myfunc(SEXP df), and it is called with a dataframe from the R side with: .Call("myfunc", somedataframe) On the C side (actually C++ side) I use code like this:

Can we use the "bytes" encoding for such environment variables invalid in the current locale? The following patch preserves CE_NATIVE for strings valid in the current UTF-8 or multibyte locale (or non-multibyte strings) but sets CE_BYTES for those that are invalid: Index: src/main/sysutils.c =================================================================== --- src/main/sysutils.c

Hello, Since people have whisperred about Rcpp, I'd like to play too. > On 11/15/2010 07:45 AM, Patrick Leyshock wrote: >> Very helpful, thank you. >> >> A couple other questions, please: >> >> 1. I've got a function written in C, named "my_c_function". In my R >> code I call this function, passing to it an INTSXP and a STRSXP, >>