similar to: What is the best way to loop over an ALTREP vector?

Sorry for post a lot of things, for the first part of code, I copied my C++ iter macro by mistake(and you can see an explicit type casting). Here is the macro definition from R_exts/Itermacros.h #define ITERATE_BY_REGION_PARTIAL(sx, px, idx, nb, etype, vtype, \ strt, nfull, expr) do { \ * const** etype *px = DATAPTR_OR_NULL(sx); *

Hi Bob, Thanks for sending around the link to that. It looks mostly right and looks like a useful onramp. There are a few things to watch out for though (I've cc'ed Romain so he's aware of these comments). @romain I hope you taake the following comments as they are intended, as help rather than attacks. The largest issue I see is that the contract for Get_region is that it *populates

On 10/25/19 11:01 AM, Tomas Kalibera wrote: > On 10/23/19 6:45 AM, Wang Jiefei wrote: >> Hi all, >> >> I found an unexpected behavior when I was trying to use the macro >> defined >> in "R_ext/Itermacros.h"? to loop over an atomic vector. Here is a >> minimum >> example: >> >> C++ code >> ``` >> #include

Hi all, I found an unexpected behavior when I was trying to use the macro defined in "R_ext/Itermacros.h" to loop over an atomic vector. Here is a minimum example: C++ code ``` #include "R_ext/Itermacros.h" #define GET_REGION_BUFSIZE 2 //Redefine the macro since C++ is not happy with the implicit type conversion #define ITERATE_BY_REGION_PARTIAL(sx, px, idx, nb, etype,

Not sure if you're using just C++ or Rcpp for C++ access but https://purrple.cat/blog/2018/10/14/altrep-and-cpp/ has some tips on using C++ w/ALTREP. > On Sep 23, 2019, at 3:17 PM, Wang Jiefei <szwjf08 at gmail.com> wrote: > > Sorry for post a lot of things, for the first part of code, I copied my C++ > iter macro by mistake(and you can see an explicit type casting). Here

Hi Gabriel, I have tried the macro and found a small issue, it seems like the macro is written in C and does an implicit type conversion(const void * to const int *), see below. While it is allowed in C, C++ seems not happy with it. Is it possible to add an explicit type casting so that it can be compatible with both language? #define ITERATE_BY_REGION_PARTIAL(sx, px, idx, nb, etype, vtype,

Thank you, Tomas. I appreciate your help. BTW, could you also add an explicit type conversion in " ITERATE_BY_REGION_PARTIAL" macro while you are fixing the bug? C++ compiler does not happy with the implicit conversion from void* to T* somehow and I have to redefine it before using the macro. Best, Jiefei On Fri, Oct 25, 2019 at 11:13 AM Tomas Kalibera <tomas.kalibera at

On 10/23/19 6:45 AM, Wang Jiefei wrote: > Hi all, > > I found an unexpected behavior when I was trying to use the macro defined > in "R_ext/Itermacros.h" to loop over an atomic vector. Here is a minimum > example: > > C++ code > ``` > #include "R_ext/Itermacros.h" > #define GET_REGION_BUFSIZE 2 > //Redefine the macro since C++ is not happy with

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 all, The coercion function defined for the ALTREP object will not be called by R when an assignment operation implicitly introduces coercion for a large ALTREP object. For example, If I create a vector of length 10, the ALTREP coercion function seems to work fine. ``` > x <- 1:10 > y <- wrap_altrep(x) > .Internal(inspect(y)) @0x000000001f9271c0 13 INTSXP g0c0 [REF(2)] I am

Benjamin, You happened to send a link which points to the OP's own package :) I think Jiefei would like to know how one can "officially" determine if an arbitrary ALTERP object belongs to a class that he owns. Regards, Denes On 10/19/20 10:22 AM, Benjamin Christoffersen wrote: > It seems as if you can you use the ALTREP macro as done in this > package:

Thank Denes for the clarification, glad to see my package got one citation from my own question:) Also, thank Benjamin for sending many useful documents. Actually, the question is related to the SharedObject package that Benjamin has pointed to. I wanna avoid sharing an object that has already been shared, so I need to check whether an object is an ALTREP that is defined in my package. Since the

Hi Gabriel, here is a simple package for reproducing the problem. https://github.com/Jiefei-Wang/testPkg Best, Jiefei On Thu, Oct 8, 2020 at 5:04 AM Gabriel Becker <gabembecker at gmail.com> wrote: > Jiefei, > > Where does the code for your altrep class live? > > Thanks, > ~G > > On Wed, Oct 7, 2020 at 4:25 AM Jiefei Wang <szwjf08 at gmail.com> wrote: >

Hi all, I'm wondering if there is any way to define a `SET_ELT` function for an ALTREP class? I see there are ` ALTINTEGER_SET_ELT` etc. functions exported in Rinternal.h, but there is no corresponding ALTREP APIs to define them. The only way to set the value of an ALTREP is through a pointer, which will require that the ALTREP data is in memory. Is it on purpose? Will there be any plan to

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

Hi all, I would like to determine if an ALTREP object is from my package, I see there is a function `ALTREP_CLASS` defined in RInternal.h but its return value is neither a `R_altrep_class_t` object nor an STRSXP representing a class name. I do not know how to correctly use it. Any suggestions? Thanks, Jiefei [[alternative HTML version deleted]]

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 Gabriel, Thanks for your explanation, I totally understand that it is almost impossible to change the data structure of STRSXP. However, what I'm proposing is not about changing the internal representation, but rather about how we design and use the ALTREP API. I might do not state the workarounds clearly as English is not my first language. Please let me explain them again in detail.

Hello from Bioconductor, I'm developing a package to share R objects across clusters using boost library. The concept is similar to mmap package: https://cran.r-project.org/web/packages/mmap/index.html . However, I have a problem when I was trying to write Dataptr_method for the alternative string. Based on my understanding, the return value of the Dataptr_method function should be a vector