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"),

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' ??? ##

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

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

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

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

With this patch, > A <- matrix(1, 2, 2) > B <- matrix(2, 3, 2) > A %*% B Error in A %*% B : non-conformable arguments of dimension (2, 2) and (3, 2) >From 205b591d4d14b5ff667325fb233a6deb08314726 Mon Sep 17 00:00:00 2001 From: Joshua Nathaniel Pritikin <jpritikin at pobox.com> Date: Fri, 5 Apr 2019 12:03:58 -0400 Subject: [PATCH] Improve non-conformable arguments error

I'd like to propose a change to the R language so that calling 'parent.env<-' on a package namespace or package imports is a runtime error. Currently the documentation warns that it's dangerous behaviour and might go away: The replacement function ?parent.env<-? is extremely dangerous as it can be used to destructively change environments in ways that violate

Hi, I would be nice if names() returned the equivalent of ls() for environments. --- a/src/main/attrib.c +++ b/src/main/attrib.c @@ -687,6 +687,8 @@ SEXP attribute_hidden do_names(SEXP call s = CAR(args); if (isVector(s) || isList(s) || isLanguage(s)) return getAttrib(s, R_NamesSymbol); + if (isEnvironment(s)) + return R_lsInternal(s, 0); return R_NilValue; }

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

… 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

Function factor() in the current development version (2009-05-22) guarantees that levels are different character strings. However, they may represent the same decimal number. The following example is derived from a posting by Stavros Macrakis in thread "Match .3 in a sequence" in March nums <- 0.3 + 2e-16 * c(-2,-1,1,2) f <- factor(nums) levels(f) # [1]