similar to: not safe to return vector pointer

Dear R Gurus, I would very much appreciate some help with this code snippit from my RODBC package. R crashes or exhibits bizarre behaviour when repeatedly fetching large numbers of rows. Examples: > odbcFetchRows(0,max=50000)->xx > odbcFetchRows(0,max=50000)->xx > odbcFetchRows(0,max=50000)->xx > odbcFetchRows(0,max=50000)->xx > odbcFetchRows(0,max=50000)->xx 3rd

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

Hi, I'd like to construct an R list object in C++, fill it with relevant data, and pass it to an R function which will return a different list object back. I have browsed through all the R manuals, and examples under tests/Embedding, but can't figure out the correct way. Below is my code snippet: #include <Rinternals.h> // Rf_initEmbeddedR and other setups already performed

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

In a C++ extension to R (v 1.8.1), I've been experimenting with a generic "push back" function to tack one value at a time onto the end of an R vector created within the extension. After calling this function a certain number of times Rgui.exe (I'm writing in Windows using Visual Studio .NET 2003) will fail with an Access Violation, which doesn't happen when I pre-allocate

I use a large real matrix, X, in C code that is passed from R and transposed in place in the C code. I would like to conserve memory and, if possible, allocate space for only one copy of X -- hence I would like to pass a pointer to the data in the X object to the C code. The Writing R Extensions manual says that neither .Call nor .External copy their arguments. They also say that these

Hal, (and everyone who might care about post increment generation)... I have an interesting question/observation. Consider this vector loop. void vec_add_const(unsigned N, short __attribute__ ((aligned (16))) *A, short __attribute__ ((aligned (16))) val) { unsigned i,j; for (i=0; i<N; i++) { for (j=0; j<N; j++) { A[i*N+j] += val; } } } The

----- Original Message ----- > From: "Sergei Larin" <slarin at codeaurora.org> > To: "Hal Finkel" <hfinkel at anl.gov> > Cc: llvmdev at cs.uiuc.edu > Sent: Friday, March 1, 2013 10:24:39 AM > Subject: Interesting post increment situation in DAG combiner > > Hal, (and everyone who might care about post increment generation)... Sergei, Perhaps

Hal, Here is my patch for the post inc case. I think it is symmetrically applicable to the pre-inc, but I have not tested it for that. I think you can clearly see my intent here - I simply select the "latest" candidate when multiple are available. Who else might be interested in this? Sergei --- Qualcomm Innovation Center, Inc. is a member of Code Aurora Forum, hosted by The

I would like to return an empty list from a C function. This I would do as: if (file.exists()) { /* do something */ } else { SEXP empty_list; PROTECT(empty_list = NEW_LIST(0)); UNPROTECT(1); return empty_list; } The PROTECT, UNPROTECT lines seemed like overkill to me, but as far as I understood the documentation this seemed like the correct usage. It seems like I could

Hello, I have some code which generates lattice objects. The function recieves serialized forms of the lattice objects which it then unserializes and then adds to an ArrayList<REXP>. REXPRaw rser = new REXPRaw( target ); //target contains the raw serialized forms of lattice objects rconn.assign("temp",rser); REXP ret =

Hey Duncan, Hard to debug? That's an understatement. Eyes bleeding.... In any case, I tried all your suggestions. To get "integer" for the final column, I had to change the code to get integers instead of strings. double[] d1 = ((REXPVector) ((RList) tableRead).get(0)).asDoubles(); double[] d2 = ((REXPVector) ((RList) tableRead).get(1)).asDoubles(); double[] d3 = ((REXPVector)

Hello, this is probably something silly which I am doing, but I cannot understand why this allocation is not happening. Here is a my C code which tries to allocate a list of size 333559, and then a matrix of size 8*333559 I thought I might be running into memory problems, but R is not even using that much (I start R with more memory and it stays constant) Also, I start R as I normally do and I

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 =

It can't be this hard, right? I really need a shove in the right direction here. Been spinning wheels for three days. Cannot get past the errors. I'm doing something wrong, obviously, since I can easily compute the Box's M right there in RStudio But I don't see what is wrong below with the coding equivalent. The entire code snippet is below. The code fails below on the call to

Thanks Duncan. I can't tell you how helpful all your terrific replies have been. I think the biggest surprise is that nobody appears to be using Java and R together like I"m trying to do. I suppose it should be a surprise since there are no books on the subject and almost no technical documentation other than a few sites here and there. ----- I originally had the "int" as the

I'm not sure what you mean. Could you please be more specific? If I print the string, I get: boxM(boxMVariable[, -5], boxMVariable[, 5]) From this code: . . . // assign the data to a variable.rConnection.assign("boxMVariable", myDf); // create a string command with that variable name.String boxVariable = "boxM(boxMVariable[, -5], boxMVariable[, 5])";

Thanks Duncan. Awesome ideas! I think we're getting closer! I tried what you suggested and got a possibly better error... . . . rConnection.assign("boxMVariable", myDf); String resultBV = "str(boxMVariable)"; // your suggestion. RESULTING ERROR: Error in format.default(nam.ob, width = max(ncn), justify = "left") : invalid 'width' argument (No idea

I try to create a big treelike list structure using the RDefines/RInternal macros. The tree carries information at each node (attribute list) and at each leaf (vector). My understanding is that for each node I add to the binary tree I have to call PROTECT(newnode = NEW_LIST(2)); and cannot UNPROTECT before I return the whole tree. Same story for node attributes and leaf vectors. However, this

Hello all, Is there a way to export C++ "unsigned" integer to R? (I am trying to parse files in "BPMAP" format, and some variables are of type unsigned int (first declared in C++) ). I know that to export signed integer to R, I can do the following in C++: int Some_INTEGER = 5; int *p_myInt; SEXP myInt; PROTECT(myInt=NEW_INTEGER(1)); myInt[0] = Some_INTEGER;