Displaying 20 results from an estimated 2000 matches similar to: "Invisible names problem"
2019 Jul 17
2
ALTREP wrappers and factors
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
2019 Jul 19
2
ALTREP wrappers and factors
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
2020 Jul 22
0
Invisible names problem
Very interesting:
> .Internal(inspect(k[i]))
@10a4bc000 14 REALSXP g0c7 [ATT] (len=20000, tl=0) 1,2,3,4,1,...
ATTRIB:
@7fa24f07fa58 02 LISTSXP g0c0 [REF(1)]
TAG: @7fa24b803e90 01 SYMSXP g0c0 [MARK,REF(5814),LCK,gp=0x6000] "names" (has value)
@10a4e4000 16 STRSXP g0c7 [REF(1)] (len=20000, tl=0)
@7fa24ba575c8 09 CHARSXP g0c1 [MARK,REF(35005),gp=0x61] [ASCII] [cached]
2010 Nov 12
1
SEXPs and slots
Hello,
I've created this class:
setClass("example",
representation (
size = "numeric",
id = "character"
)
)
Suppose I create a new instance of this class:
> x <- new("example", 4, "id_value")
This creates an S4 object with two slots. Am I correct in thinking that
slots are "filled" by SEXPs?
2016 Aug 05
2
Extra copies of objects in environments when using $ operator?
My understanding is that R will not make copies of lists if there is
only one reference to the object. However, I've encountered a case
where R does make copies, even though (I think) there should be only
one reference to the object. I hope that someone could shed some light
on why this is happening.
I'll start with a simple example. Below, x is a list with one element,
and changing that
2020 Jan 09
6
Get memory address of an R data frame
Hello,
I would like for my C function to be able to manipulate some values stored in an R data frame.
To achieve this, a need the (real) memory address where the R data frame stores its data (hopefully in a contiguous way). Then, from R, I call the C function and passing this memory address as a parameter.
The question: how can we get the memory address of the R data frame?
Thank you!
L.
2012 Jun 06
2
suggest that as.double( something double ) not make a copy
I've been playing with passing arguments to .C(), and found that replacing
as.double(x)
with
if(is.double(x)) x else as.double(x)
saves time and avoids one copy, in the case that x is already double.
I suggest modifying as.double to avoid the extra copy and just
return x, when x is already double. Similarly for as.integer, etc.
[[alternative HTML version deleted]]
2011 Nov 24
1
Confused about NAMED
Hi,
I expected NAMED to be 1 in all these three cases. It is for one of them,
but not the other two?
> R --vanilla
R version 2.14.0 (2011-10-31)
Platform: i386-pc-mingw32/i386 (32-bit)
> x = 1L
> .Internal(inspect(x)) # why NAM(2)? expected NAM(1)
@2514aa0 13 INTSXP g0c1 [NAM(2)] (len=1, tl=0) 1
> y = 1:10
> .Internal(inspect(y)) # NAM(1) as expected but why different to x?
2020 Oct 07
2
Coercion function does not work for the ALTREP object
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
2014 Mar 17
1
Deep copy of factor levels?
Hi
It seems that selecting an element of a factor will copy its levels
(Ubuntu 13.04, R 3.0.2). Below is the output of a script that creates a
factor with 10000 elements and then calls as.list() on it. The new
object seems to use more than 700 MB, and inspection of the levels of
the individual elements of the list suggest that they are distinct objects.
Perhaps some performance gain could
2019 Jul 18
0
ALTREP wrappers and factors
Hi Kylie,
For your question, I don't think a wrapper can completely solve your
problem. The duplication occurs since your variable y has more than 1
reference number( Please see highlighted), so even you have a wrapper, any
changes on the value of the wrapper still can trigger the duplication.
> .Internal(inspect(y))
> @7fb0ce78c0f0 13 INTSXP g0c0 *[NAM(7)]* matter vector (mode=3,
2020 Oct 08
1
Coercion function does not work for the ALTREP object
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:
>
2014 Apr 02
0
special handling of row.names
Hello,
I think there is an inconsistency in the handling of the compact form of the row.names attributes.
When n is the number of rows of a data.frame, the compact form is c(NA_integer_,-n), as in:
> d <- data.frame(x=1:10)
> .Internal(inspect(d))
@104f174a8 19 VECSXP g0c1 [OBJ,NAM(2),ATT] (len=1, tl=0)
@103a7dc60 13 INTSXP g0c4 [] (len=10, tl=0) 1,2,3,4,5,...
ATTRIB:
@104959380
2016 May 20
2
identical on closures
I'm confused by this:
> identical(function() {}, function() {})
[1] FALSE
Yet, after loading the Matrix package (which redefines det), the
following is checked (in library.checkConflicts):
> identical(get("det", baseenv()), get("det", asNamespace("Matrix")),
ignore.environment=T)
[1] TRUE
I've looked at the code in identical.c and for closures it
2010 Nov 15
1
SEXP and slots
Hello,
Since people have whisperred about Rcpp, I'd like to play too.
> On 11/15/2010 07:45 AM, Patrick Leyshock wrote:
>> Very helpful, thank you.
>>
>> A couple other questions, please:
>>
>> 1. I've got a function written in C, named "my_c_function". In my R
>> code I call this function, passing to it an INTSXP and a STRSXP,
>>
2019 Jan 15
4
Objectsize function visiting every element for alt-rep strings
I have a toy alt-rep string package that generates randomly seeded strings.
example:
library(altstringisode)
x <- altrandomStrings(1e8)
head(x)
[1] "2PN0bdwPY7CA8M06zVKEkhHgZVgtV1" "5PN2qmWqBlQ9wQj99nsQzldVI5ZuGX" ... etc
object.size(1e8)
Object.size will call the set_altstring_Elt_method for every single
element, materializing (slowly) every element of the vector. This
2013 Aug 18
1
How does R_UnboundValue and removing variables work?
Reading "R Internals" made me believe that R_UnboundValue was a placeholder
that would be skipped over in variable lookup. viz. the section of R
Internals "Hash tables" says "items are not actually deleted but have their
value set to R_UnboundValue.", which seems to align with what I read in
envir.c.
So, I reasoned, if I have a function that returns R_UnboundValue,
2009 Sep 29
3
How do I access class slots from C?
Hi
I'm trying to implement something similar to the following R snippet using
C. I seem to have hit the wall on accessing class slots using C.
library(fPortfolio)
lppData <- 100 * LPP2005.RET[, 1:6]
ewSpec <- portfolioSpec()
nAssets <- ncol(lppData)
setWeights(ewSpec) <- rep(1/nAssets, times = nAssets)
ewPortfolio <- feasiblePortfolio(
data = lppData,
spec = ewSpec,
2020 Jan 09
0
Get memory address of an R data frame
Hi Lille,
Is it possible you're looking for tracemem() or inspect() ?
> x <- data.frame(z = 1:10)> tracemem(x)[1] "<0x55aa743e0bc0>"
> x[1] <- 2Ltracemem[0x55aa743e0bc0 -> 0x55aa778f6ad0]:
tracemem[0x55aa778f6ad0 -> 0x55aa778f6868]: [<-.data.frame [<-
tracemem[0x55aa778f6868 -> 0x55aa778f5b48]: [<-.data.frame [<-
>
2020 Sep 08
4
Operations with long altrep vectors cause segfaults on Windows
>>>>> Martin Maechler
>>>>> on Tue, 8 Sep 2020 10:40:24 +0200 writes:
>>>>> Hugh Parsonage
>>>>> on Tue, 8 Sep 2020 18:08:11 +1000 writes:
>> I can only reproduce on Windows, but reliably (both 4.0.0 and 4.0.2):
>> $> R --vanilla
>> x <- c(0L, -2e9:2e9)
>> # > Segmentation