similar to: .Internal

Hi, To make a calculation (an innermost loop) that uses optimize faster, I think I should write things in C. Is it possible to call fmin, which is called by optimize, from C? It is not listed in Writing R extensions, but I found double Brent_fmin(double ax, double bx, double (*f)(double, void *), void *info, double tol); in Applic.h. Is this the function I am looking for?

Hello, I'm developing a package (lazyvec) that makes full use of the ALTREP framework (R >= 3.6.0). One application of the package is to wrap existing ALTREP vectors in a new ALTREP vector and pass all calls from R to the contained object. The purpose of this is to provide a diagnostic framework for working with ALTREP vectors and show information about internal calls. The package builds

thanks for clearing that up, so these methods are actually not meant to be exported on Windows and OSX? Some of the ALTREP methods that now use 'attribute_hidden' would be very useful to packages that aim to be ALTREP aware, should the currently (exported) API be considered final? thanks for your time & best, Mark On Tue, Jun 4, 2019 at 6:52 PM Tierney, Luke <luke-tierney at

Hello all, I don't know if it is possible, but I would like to use do.call in C code in my package. The function do.call is defined as > do.call function (what, args, quote = FALSE, envir = parent.frame()) { if (!is.list(args)) stop("second argument must be a list") if (quote) { enquote <- function(x) as.call(list(as.name("quote"),

Hi Gabriel, thanks for your detailed explanation, that definitely clarifies the design choices that were made in setting up the ALTREP framework and I can see how those choices make sure existing code won't break. My specific use-case for wanting to check whether a vector is an ALTREP is the following: the fst package wraps an external C++ library (fstlib, independent from R) that was made

On Fri, 10 Feb 2023 23:38:55 -0600 Spencer Graves <spencer.graves at prodsyse.com> wrote: > I have a 4.54 GB file that I'm trying to read in chunks using > "scan(..., skip=__)". It works as expected for small values of > "skip" but goes into an infinite loop for "skip=1e11" and similar > large values of skip: I cannot even interrupt it; I

When large calls cause errors R may stall for extended periods.? This is particularly likely to happen with `do.call`, as in this example with a 24 second stall: ??? x <- runif(1e7) ??? system.time(do.call(paste0, list(abs, x)))? # intentional error ??? ## Error in (function (..., collapse = NULL)? : ??? ##?? cannot coerce type 'builtin' to vector of type 'character' ??? ##

Hi, I’d like to re-propose adding intrinsics for fmin / fmax. These can be used to implement the equivalent libm functions as defined in C99 and OpenCL, which R600 and AArch64 at least have instructions with the same semantics. This is not equivalent to a simple fcmp + select due to its handling of NaNs. This has been proposed before, but never delivered

I've been inspired to look at the R source code by some strange timing results that I wrote about on my blog at radfordneal.wordpress.com (see the posts on "Speeding up parentheses..." and "Two surprising things...". I discovered that the strange speed advantage of curly brackets over parentheses is partially explained by an inefficiency in the evalList and

… actually, now that I’m able double-check this, I’m quite surprised to find that we didn’t define fmax(+0,–0) in IEEE–754, which says [paraphrased]: minNum(x,y) is x if x < y, y if y < x, and the number if one is a number and the other is NaN. Otherwise, it is either x or y (this means results might differ among implementations). So I think your proposed semantics are perfectly

This is a problem with all floating point folding, not just with these operations. What Matt is proposing is consistent with how we fold other libm intrinsics. —Owen > On Aug 18, 2014, at 1:22 AM, Mueller-Roemer, Johannes Sebastian <Johannes.Sebastian.Mueller-Roemer at igd.fraunhofer.de> wrote: > > Wouldn’t it be better to use the target’s implementation (if there is one)

Hi Carter, I would strongly advise you against this direction. I’m aware of two directions that existing languages go in defining min/max operations: - IEEE 754, C, Fortran, Matlab, OpenCL, and HLSL all define it not to propagate NaNs - C++ (std::min/std::max) and OpenGL define it in the trinary operator manner: (a < b) ? a : b What you’re proposing does not match any existing languages

Chain?of?calls?of?C?functions?in?coerce.c?for?as.character(<logical>)?in?R: do_asatomic ascommon coerceVector coerceToString StringFromLogical?(for?each?element) The?definition?of?'StringFromLogical'?in?coerce.c?: attribute_hidden?SEXP?StringFromLogical(int?x,?int?*warn) { ????int?w; ????formatLogical(&x,?1,?&w); ????if?(x?==?NA_LOGICAL)?return?NA_STRING;

Dear all, [system and version information below] I am trying to modify a C function for finding the root of an expression. The function is to be called from R as .Call with input parameters: f: expression for which we will find the root guesses: interval for the solution stol: tolerance rho: environment The original functions I use are: SEXP mkans(double x) { SEXP ans; PROTECT(ans =

Dear all, [system and version information below] I am trying to modify a C function for finding the root of an expression. The function is to be called from R as .Call with input parameters: f: expression for which we will find the root guesses: interval for the solution stol: tolerance rho: environment The original functions I use are: SEXP mkans(double x) { SEXP ans; PROTECT(ans =

Luke, thanks for considering the issue.? I would like to try to separate the problem into two parts, as I _think_ your comments address primarily part 2 below: 1. How can we avoid significant and possibly crippling ?? stalls on error with these non-standard calls. 2. What is the best way to view these non-standard calls. I agree that issue 2. requires further thought and discussion under a

Hi, I have spotted a minor bug in do_strptime() function. Here is a patch: ?--- a/src/main/datetime.c +++ b/src/main/datetime.c @@ -1048,7 +1048,7 @@ SEXP attribute_hidden do_strptime(SEXP call, SEXP op, SEXP args, SEXP env) if(!isString((x = CAR(args)))) error(_("invalid '%s' argument"), "x"); if(!isString((sformat = CADR(args))) ||

A colleague sent me the following: If you specify probabilities in the 'sample' function and forget to type 'prob=...', then you get nonsense. E.g. sample(1:10,1,c(0,0,0,0,1,0,0,0,0,0)) does not filter '5', while sample(1:10,1,prob=c(0,0,0,0,1,0,0,0,0,0)) does it correctly. I wish this would return an error because the

Hi, The specification for the llvm.minnum/llvm.maxnum intrinsics is too unclear right now to usefully optimize. There are two problems. First the expected behavior for signaling NaNs needs to be clarified. Second, whether the returned value is expected to be canonicalized (as if by llvm.canonicalize). Currently according to the LangRef: Follows the IEEE-754 semantics for minNum, which also

We also have a few other suggestions and wishes about backtrace storage and display on the one hand, and display of constructed calls on the other hand. Perhaps it would be better to open a different wishlist item for traceback() to keep the discussions focused? FWIW I think deparsing backtraces lazily is a great idea. Displaying 1 line per call by default in interactive sessions, while being