similar to: [ALTREP] What is the meaning of the return value of Is_sorted and No_NA function?

Hi Jiefei, The meanings of the return values for sortedness can be found in RInternals.h, and are as follows: /* ALTREP sorting support */ enum {SORTED_DECR_NA_1ST = -2, SORTED_DECR = -1, UNKNOWN_SORTEDNESS = INT_MIN, /*INT_MIN is NA_INTEGER! */ SORTED_INCR = 1, SORTED_INCR_NA_1ST = 2, KNOWN_UNSORTED = 0}; The default value there is NA_INTEGER (ie INT_MIN),

Hi Gabriel, Thanks for your answer and future update plan. Somehow this email has been delayed for a week, so there might be a wired reply from me saying that I have found the answer from the R source code, it was sent from me last week. Hopefully, this reply will not cost another week to post:) As a side note, I like the idea that defining a macro for sortedness, and I can see why we can only

Hi, I've found the answers to my questions: 1. For sort function, here are some macros defined in Rinternal.h: /* ALTREP sorting support */ enum {SORTED_DECR_NA_1ST = -2, SORTED_DECR = -1, UNKNOWN_SORTEDNESS = INT_MIN, /*INT_MIN is NA_INTEGER! */ SORTED_INCR = 1, SORTED_INCR_NA_1ST = 2, KNOWN_UNSORTED = 0}; The macro names are pretty self-explanatory. The

Hello Luke and Gabriel, Thank you very much for your quick responses. The explanation of STDVEC is very helpful and I appreciate it! For the wrapper, I have a few new questions. 1. Like Luke said a mutable object is not possible. However, I noticed that there is one extra argument *deep* in the function duplicate. I've googled all the available documentation for ALTREP but I did not find

Hello, I have encountered two bugs when using ALTREP APIs. 1. STDVEC_DATAPTR >From RInternal.h file it has a comment: /* ALTREP support */ > void *(STDVEC_DATAPTR)(SEXP x); However, this comment might not be true, the easiest way to verify it is to define a C++ function: void C_testFunc(SEXP a) > { > STDVEC_DATAPTR(a); > } and call it in R via > a=1:10 > >

Hi Jiefei and Kylie, Great to see people engaging with the ALTREP framework and identifying places we may need more tooling. Comments inline. On Thu, Jul 18, 2019 at 12:22 PM King Jiefei <szwjf08 at gmail.com> wrote: > > If that is the case and you are 100% sure the reference number should be 1 > for your variable *y*, my solution is to call *SET_NAMED *in C++ to reset > the

Hello, I?m experimenting with ALTREP and was wondering if there is a preferred way to create an ALTREP wrapper vector without using .Internal(wrap_meta(?)), which R CMD check doesn?t like since it uses an .Internal() function. I was trying to create a factor that used an ALTREP integer, but attempting to set the class and levels attributes always ended up duplicating and materializing the

Hi, thank you for taking the time and reading my question. My question is twofold: 1. I have several matrices with variables and one matrix with water levels. I want to predict the water level with the data in the other matrices. Basically, * mod<-lm(matrix1 ~ matrix2+matrix3)* ( What looks like a minus is meant to be the wiggly minus.) Of course I could dissemble the matrices and paste

I ran into strange behavior when removing names. Two ways of removing names: i <- rep(1:4, length.out=20000) k <- c(a=1, b=2, c=3, d=4) x1 <- unname(k[i]) x2 <- k[i] x2 <- unname(x2) Are they identical? identical(x1,x2) # TRUE but no identical(serialize(x1,NULL),serialize(x2,NULL)) # FALSE But problem is with serialization type 3, cause:

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

In the code of functions 'order' and 'sort.list' in R 3.5.0 alpha (in https://svn.r-project.org/R/branches/R-3-5-branch/src/library/base/R/sort.R), in "fastpass, take advantage of ALTREP metadata", there is "try the reverse since that's easy too...". If it succeeds, ties are reordered, violating stability of sorting. Example: x <- sort(c(1, 1, 3)) x # 1

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

Jiefei, Inline. On Thu, May 16, 2019 at 2:30 PM ??? <szwjf08 at gmail.com> wrote: > Hello Luke and Gabriel, > > Thank you very much for your quick responses. The explanation of STDVEC is > very helpful and I appreciate it! For the wrapper, I have a few new > questions. > > > 1. Like Luke said a mutable object is not possible. However, I noticed > that there is

Hi Jiefei, Thanks for tryingout the ALTREP stuff and letting us know how it is going. That said I don't think either of these are bugs, per se, but rather a misunderstanding of the API. Details inline. On Thu, May 16, 2019 at 11:57 AM ??? <szwjf08 at gmail.com> wrote: > Hello, > > I have encountered two bugs when using ALTREP APIs. > > 1. STDVEC_DATAPTR > > From

On Thu, Oct 17, 2019 at 11:22 AM David Greene via llvm-dev < llvm-dev at lists.llvm.org> wrote: > hameeza ahmed via llvm-dev <llvm-dev at lists.llvm.org> writes: > > > Hello, > > I want to study the individual O3 optimizations. For this I am using > > following commands, but unable to replicate O3 behavior. > > > > 1.

I run matrix multiplication code with both the approaches o3 at clang and o3 at opt. clang o3 is about 2.97x faster than opt o3. On Mon, Oct 21, 2019 at 8:24 AM Neil Nelson <nnelson at infowest.com> wrote: > is_sorted.cpp > bool is_sorted(int *a, int n) { > > for (int i = 0; i < n - 1; i++) > > if (a[i] > a[i + 1]) > return false; > return

If I have loaded the C code: SEXP altrep_STRING_IS_SORTED(SEXP x) { return ScalarInteger(STRING_IS_SORTED(x)); } and defined the function: issort <- function(x) .Call("altrep_STRING_IS_SORTED",x) I am seeing the following results in R 3.5.1/Linux: > issort(LETTERS) [1] NA > issort(as.character(1:100)) ## should return NA [1] 1 >

Inside of the anyNA() function, it will use the legacy any(is.na()) code if x is an OBJECT(). If x is a vector of POSIXct, it will be an OBJECT(), but it is also TYPEOF(x) == REALSXP. Therefore, it will skip the faster ITERATE_BY_REGION, which is typically 5x faster in my testing. Is the OBJECT() condition really necessary, or could it be moved after the switch() for the individual TYPEOF(x)

I believe the performance of isUnsorted() in sort.c could be improved by calling REAL() once (outside of the for loop), rather than calling it twice inside the loop. As an aside, it is implemented in the faster way in doSort() (sort.c line 401). The example below shows the performance improvement for a vectors of double of moving REAL() outside the for loop. # example as implemented in

Hi Mark, So depending pretty strongly on what you mean by "ALTREP aware", packages aren't necessarily supposed to be ALTREP aware. What I mean by this is that as of right now, ALTREP objects are designed to be interacted with by non-ALTREP-implementing package code, *more-or-less *exactly as standard (non-AR) SEXPs are: via the published C API. The more or less comes from the fact