similar to: R C API resize matrix

Matrix is just a vector with the dim attribute. Assuming it is not referenced by anyone, you can set any values to the dim attribute. As for the vector, you can use SET_LENGTH() to shorten it - but I'm not sure how official it is - it was originally designed to work, but there were abuses of TRUELENGTH so not sure where we stand now (shortened vectors used to fool the garbage collector as far

Hi, Using the R C PAI, is there a way to convert to convert STRSXP or INTSXP to factor. The idea would be to do in C something similar to the "factor" function (example below): > letters[1:5] # [1] "a" "b" "c" "d" "e" > factor(letters[1:5]) # [1] a b c d e # Levels: a b c d e There is the function setAttrib the levels of a SXP

Hello. I'm trying to read a delimited file. I'm a little new to the R api. In the program, I do something like this... /*****************************/ SEXP retval; PROTECT(retval = allocMatrix(STRSXP,1,names.dim)); int r_eltctr = 0; while(!myfile.eof()) { SET_LENGTH(retval,r_eltctr+num_of_fields); for(int i = 0;numofcolumns; ++i) { INTEGER(retval)[r_eltctr++] = 1;/*some

I think you are confusing package and function here. Plus some of the R Core packages, that you mention, contain functions that should probably be replaced by functions with better implementation from packages on CRAN. Best regards Morgan On Fri, 11 Oct 2019 15:22 Joris Meys, <jorismeys at gmail.com> wrote: > > > On Fri, Oct 11, 2019 at 3:55 PM Morgan Morgan <morgan.emailbox

How do you prove usefulness of a feature? Do you have an example of a feature that has been added after proving to be useful in the package space first? Thank you, Morgan On Fri, 11 Oct 2019 13:53 Michael Lawrence, <lawrence.michael at gene.com> wrote: > Thanks for this interesting suggestion, Morgan. While there is no strict > criteria for base R inclusion, one criterion relevant

Hi My code is as following: #include <R.h> #include <Rinternals.h> //* the Projector part *// void Projector(double *L, int *dimL, double *G, int *dimG, double *W, int *dimW, int *xymod, int *dimxy, double *modif, int *dimif, double *Lsum) { ...} //* the interface part *// #define getDim(A) INTEGER(coerceVector(getAttrib(A,R_DimSymbol), INTSXP)) SEXP Projector5(SEXP L, SEXP G,

On 6/30/20 1:06 PM, Jan Gorecki wrote: > It is quite known that R documentation on R C api could be improved... Please see "5.11 Evaluating R expressions from C" from "Writing R Extensions" Best Tomas > Still R-package-devel mailing list should be preferred for this kind > of questions. > Not sure if that is the best way, but works. > > call_to_sum <-

> On Wednesday, May 20, 2020, 7:00:09 AM EDT, peter dalgaard <pdalgd at gmail.com> wrote: > > Expected, see FAQ 7.31. > > You just can't trust == on FP operations. Notice also Additionally, since you're implementing a "mean" function you are testing against R's mean, you might want to consider that R uses a two-pass calculation[1] to reduce floating

On Fri, 11 Oct 2019 10:45 Duncan Murdoch, <murdoch.duncan at gmail.com> wrote: > On 11/10/2019 6:44 a.m., Morgan Morgan wrote: > > Hi All, > > > > I was looking for a function to find a small matrix inside a larger > matrix > > in R similar to the one described in the following link: > > > > >

Hi, It sometimes happens that some packages get included to R like for example the parallel package. I was wondering if there is a process to decide whether or not to include a package in the core implementation of R? For example, why not include the Rcpp package, which became for a lot of user the main tool to extend R? What is our view on the (not so well known) dotCall64 package which is an

Hi, I am wondering if the below is possible? Let's assume I have the following expression: 1:10 < 5 Is there a way at the R C API level to only evaluate the 5th element (i.e 5 < 5) instead of evaluating the whole expression and then select the 5th element in the logical vector? Thank you Best regards Morgan [[alternative HTML version deleted]]

Hi, Hope you are well. I was wondering if there is a function at C level that is equivalent to mtcars$carb or .subset2(mtcars, "carb"). If I have the index of the column then the answer would be VECTOR_ELT(df, asInteger(idx)) but I was wondering if there is a way to do it directly from the name of the column without having to loop over columns names to find the index? Thank you Best

As the original coder (in mid 1970s) of BFGS, CG and Nelder-Mead in optim(), I've been pushing for some time for their deprecation. They aren't "bad", but we have better tools, and they are in CRAN packages. Similarly, I believe other optimization tools in the core (optim::L-BFGS-B, nlm, nlminb) can and should be moved to packages (there are already 2 versions at least of LBFGS

Hello R-dev, Yesterday, while I was testing the newly implemented function pmean in package kit, I noticed a mismatch in the output of the below R expressions. set.seed(123) n=1e3L idx=5 x=rnorm(n) y=rnorm(n) z=rnorm(n) a=(x[idx]+y[idx]+z[idx])/3 b=mean(c(x[idx],y[idx],z[idx])) a==b # [1] FALSE For idx= 1, 2, 3, 4 the last line is equal to TRUE. For 5, 6 and many others the difference is small

Hi All, I was reading the R extension manual section 5.11 ( Evaluating R expression from C) and I tried to build a simple call to the sum function. Please see below. call_to_sum <- inline::cfunction( language = "C", sig = c(x = "SEXP"), body = " SEXP e = PROTECT(lang2(install(\"sum\"), x)); SEXP ans = PROTECT(eval(e, R_GlobalEnv)); UNPROTECT(2); return

Hi, I am writing an R package with two functions in C++. So far everything works. Now, i would like to write a third function which would use a pointer (it is a pointer to a class object) created by first function. I tried placing this pointer outside of the function definitions (i.e to make it global) but when called in the 3rd function i get > *** caught bus error *** address 0x0,

Hi, I am writing an R package with two functions in C++. So far everything works. Now, i would like to write a third function which would use a pointer (it is a pointer to a class object) created by first function. I tried placing this pointer outside of the function definitions (i.e to make it global) but when called in the 3rd function i get > *** caught bus error *** address 0x0,

Dear R-lister, is there any function for Meta Analysis in R? (like homogeneity an, risk differences, relative riskm amd odds ratios? Many thanks, Edwin

Hi All, I have some questions regarding the R C API. Let's assume I have a function which is defined as follows: R file: myfunc <- function(a, b, ...) .External(Cfun, a, b, ...) C file: SEXP Cfun(SEXP args) { args = CDR(args); SEXP a = CAR(args); args = CDR(args); SEXP b = CAR(args); args = CDR(args); /* continue to do something with remaining arguments in "..."

Also note that the functionality discussed could be regarded as a generalization of matrix multiplication where * and + are general functions and in this case we have * replaced by == and + replaced by &. On Fri, Oct 11, 2019 at 10:46 AM Gabor Grothendieck <ggrothendieck at gmail.com> wrote: > > Using the example in the link here are two one-liners: > > A <-