Re: [R] The L Word
Thank you all for the answers.
So if I may extend on the question -
When is it important to use 'Literal integer'?
Under what situations could not using it cause problems?
Is it a matter of efficiency or precision or both?
Thanks,
Tal
Contact
Details:---
Contact me: tal.gal...@gmail.com | 972-52-7275845
Read me: www.talgalili.com (Hebrew) | www.biostatistics.co.il (Hebrew) |
www.r-statistics.com (English)
--
On Wed, Feb 23, 2011 at 6:15 PM, Tsjerk Wassenaar tsje...@gmail.com wrote:
Hi Gene,
It means 'Literal integer'.
So 1L is a proper integer 1, and 0L is a proper integer 0.
Hope it helps,
Tsjerk
On Wed, Feb 23, 2011 at 5:08 PM, Gene Leynes gleyne...@gmail.com wrote:
I've been wondering what L means in the R computing context, and was
wondering if someone could point me to a reference where I could read
about
it, or tell me what it's called so that I can search for it myself. (L
by
itself is a little too general for a search term).
I encounter it in strange places, most recently in the save
documentation.
save(..., list = character(0L),
file = stop('file' must be specified),
ascii = FALSE, version = NULL, envir = parent.frame(),
compress = !ascii, compression_level,
eval.promises = TRUE, precheck = TRUE)
I remember that you can also find it when you step inside an apply
function:
sapply(1:10, function(x)browser())
Called from: FUN(1:10[[1L]], ...)
I apologize for being vague, it's just something that I would like to
understand about the R language (the R word).
Thank you!
Gene
[[alternative HTML version deleted]]
__
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PLEASE do read the posting guide
http://www.R-project.org/posting-guide.html
and provide commented, minimal, self-contained, reproducible code.
--
Tsjerk A. Wassenaar, Ph.D.
post-doctoral researcher
Molecular Dynamics Group
* Groningen Institute for Biomolecular Research and Biotechnology
* Zernike Institute for Advanced Materials
University of Groningen
The Netherlands
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Re: [R] The L Word
On Thu, 24 Feb 2011, Tal Galili wrote:
Thank you all for the answers.
So if I may extend on the question -
When is it important to use 'Literal integer'?
Under what situations could not using it cause problems?
Is it a matter of efficiency or precision or both?
Efficiency: it avoids unnecessary type conversions. For example
length(x) 1
has to coerce the lhs to double. We have converted the base code to
use integer constants because such small efficiency gains can add up.
Integer vectors can be stored more compactly than doubles, but that is
not going to help for length 1:
object.size(1)
48 bytes
object.size(1L)
48 bytes
(32-bit system).
Thanks,
Tal
Contact
Details:---
Contact me: tal.gal...@gmail.com | 972-52-7275845
Read me: www.talgalili.com (Hebrew) | www.biostatistics.co.il (Hebrew) |
www.r-statistics.com (English)
--
On Wed, Feb 23, 2011 at 6:15 PM, Tsjerk Wassenaar tsje...@gmail.com wrote:
Hi Gene,
It means 'Literal integer'.
So 1L is a proper integer 1, and 0L is a proper integer 0.
Hope it helps,
Tsjerk
On Wed, Feb 23, 2011 at 5:08 PM, Gene Leynes gleyne...@gmail.com wrote:
I've been wondering what L means in the R computing context, and was
wondering if someone could point me to a reference where I could read
about
it, or tell me what it's called so that I can search for it myself. (L
by
itself is a little too general for a search term).
I encounter it in strange places, most recently in the save
documentation.
save(..., list = character(0L),
file = stop('file' must be specified),
ascii = FALSE, version = NULL, envir = parent.frame(),
compress = !ascii, compression_level,
eval.promises = TRUE, precheck = TRUE)
I remember that you can also find it when you step inside an apply
function:
sapply(1:10, function(x)browser())
Called from: FUN(1:10[[1L]], ...)
I apologize for being vague, it's just something that I would like to
understand about the R language (the R word).
Thank you!
Gene
[[alternative HTML version deleted]]
__
R-help@r-project.org mailing list
https://stat.ethz.ch/mailman/listinfo/r-help
PLEASE do read the posting guide
http://www.R-project.org/posting-guide.html
and provide commented, minimal, self-contained, reproducible code.
--
Tsjerk A. Wassenaar, Ph.D.
post-doctoral researcher
Molecular Dynamics Group
* Groningen Institute for Biomolecular Research and Biotechnology
* Zernike Institute for Advanced Materials
University of Groningen
The Netherlands
__
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and provide commented, minimal, self-contained, reproducible code.
--
Brian D. Ripley, rip...@stats.ox.ac.uk
Professor of Applied Statistics, http://www.stats.ox.ac.uk/~ripley/
University of Oxford, Tel: +44 1865 272861 (self)
1 South Parks Road, +44 1865 272866 (PA)
Oxford OX1 3TG, UKFax: +44 1865 272595
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Re: [R] The L Word
On 02/24/2011 11:20 AM, Prof Brian Ripley wrote:
On Thu, 24 Feb 2011, Tal Galili wrote:
Thank you all for the answers.
So if I may extend on the question -
When is it important to use 'Literal integer'?
Under what situations could not using it cause problems?
Is it a matter of efficiency or precision or both?
Efficiency: it avoids unnecessary type conversions. For example
length(x) 1
has to coerce the lhs to double. We have converted the base code to use integer
constants because such small efficiency gains can add up.
Integer vectors can be stored more compactly than doubles, but that is not going
to help for length 1:
object.size(1)
48 bytes
object.size(1L)
48 bytes
(32-bit system).
see:
n - 0L : 100L
szi - sapply (n, function (n) object.size (integer (n)))
szd - sapply (n, function (n) object.size (double (n)))
plot (n, szd)
points (n, szi, col = red)
Thanks,
Tal
Contact
Details:---
Contact me: tal.gal...@gmail.com | 972-52-7275845
Read me: www.talgalili.com (Hebrew) | www.biostatistics.co.il (Hebrew) |
www.r-statistics.com (English)
--
On Wed, Feb 23, 2011 at 6:15 PM, Tsjerk Wassenaar tsje...@gmail.com wrote:
Hi Gene,
It means 'Literal integer'.
So 1L is a proper integer 1, and 0L is a proper integer 0.
Hope it helps,
Tsjerk
On Wed, Feb 23, 2011 at 5:08 PM, Gene Leynes gleyne...@gmail.com wrote:
I've been wondering what L means in the R computing context, and was
wondering if someone could point me to a reference where I could read
about
it, or tell me what it's called so that I can search for it myself. (L
by
itself is a little too general for a search term).
I encounter it in strange places, most recently in the save
documentation.
save(..., list = character(0L),
file = stop('file' must be specified),
ascii = FALSE, version = NULL, envir = parent.frame(),
compress = !ascii, compression_level,
eval.promises = TRUE, precheck = TRUE)
I remember that you can also find it when you step inside an apply
function:
sapply(1:10, function(x)browser())
Called from: FUN(1:10[[1L]], ...)
I apologize for being vague, it's just something that I would like to
understand about the R language (the R word).
Thank you!
Gene
[[alternative HTML version deleted]]
__
R-help@r-project.org mailing list
https://stat.ethz.ch/mailman/listinfo/r-help
PLEASE do read the posting guide
http://www.R-project.org/posting-guide.html
and provide commented, minimal, self-contained, reproducible code.
--
Tsjerk A. Wassenaar, Ph.D.
post-doctoral researcher
Molecular Dynamics Group
* Groningen Institute for Biomolecular Research and Biotechnology
* Zernike Institute for Advanced Materials
University of Groningen
The Netherlands
__
R-help@r-project.org mailing list
https://stat.ethz.ch/mailman/listinfo/r-help
PLEASE do read the posting guide
http://www.R-project.org/posting-guide.html
and provide commented, minimal, self-contained, reproducible code.
[[alternative HTML version deleted]]
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PLEASE do read the posting guide http://www.R-project.org/posting-guide.html
and provide commented, minimal, self-contained, reproducible code.
--
Claudia Beleites
Dipartimento dei Materiali e delle Risorse Naturali
Università degli Studi di Trieste
Via Alfonso Valerio 6/a
I-34127 Trieste
phone: +39 0 40 5 58-37 68
email: cbelei...@units.it
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Re: [R] The L Word
This came up at least once before, with regard to where it is
documented:
http://r.789695.n4.nabble.com/Where-are-usages-like-quot-2L-quot-documented-tt831061.html
I haven't looked around much to see if the documentation has changed,
but in a quick look at ?integer I don't see the concept mentioned. Of
course, it could be somewhere else. But, the concept is pretty
straightfoward.
Bryan
Prof. Bryan Hanson
Dept of Chemistry Biochemistry
DePauw University
602 S. College Ave
Greencastle IN 46135 USA
On Feb 24, 2011, at 3:13 AM, Tal Galili wrote:
Thank you all for the answers.
So if I may extend on the question -
When is it important to use 'Literal integer'?
Under what situations could not using it cause problems?
Is it a matter of efficiency or precision or both?
Thanks,
Tal
Contact
Details:---
Contact me: tal.gal...@gmail.com | 972-52-7275845
Read me: www.talgalili.com (Hebrew) | www.biostatistics.co.il
(Hebrew) |
www.r-statistics.com (English)
--
On Wed, Feb 23, 2011 at 6:15 PM, Tsjerk Wassenaar
tsje...@gmail.com wrote:
Hi Gene,
It means 'Literal integer'.
So 1L is a proper integer 1, and 0L is a proper integer 0.
Hope it helps,
Tsjerk
On Wed, Feb 23, 2011 at 5:08 PM, Gene Leynes gleyne...@gmail.com
wrote:
I've been wondering what L means in the R computing context, and was
wondering if someone could point me to a reference where I could
read
about
it, or tell me what it's called so that I can search for it
myself. (L
by
itself is a little too general for a search term).
I encounter it in strange places, most recently in the save
documentation.
save(..., list = character(0L),
file = stop('file' must be specified),
ascii = FALSE, version = NULL, envir = parent.frame(),
compress = !ascii, compression_level,
eval.promises = TRUE, precheck = TRUE)
I remember that you can also find it when you step inside an apply
function:
sapply(1:10, function(x)browser())
Called from: FUN(1:10[[1L]], ...)
I apologize for being vague, it's just something that I would like
to
understand about the R language (the R word).
Thank you!
Gene
[[alternative HTML version deleted]]
__
R-help@r-project.org mailing list
https://stat.ethz.ch/mailman/listinfo/r-help
PLEASE do read the posting guide
http://www.R-project.org/posting-guide.html
and provide commented, minimal, self-contained, reproducible code.
--
Tsjerk A. Wassenaar, Ph.D.
post-doctoral researcher
Molecular Dynamics Group
* Groningen Institute for Biomolecular Research and Biotechnology
* Zernike Institute for Advanced Materials
University of Groningen
The Netherlands
__
R-help@r-project.org mailing list
https://stat.ethz.ch/mailman/listinfo/r-help
PLEASE do read the posting guide
http://www.R-project.org/posting-guide.html
and provide commented, minimal, self-contained, reproducible code.
[[alternative HTML version deleted]]
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PLEASE do read the posting guide http://www.R-project.org/posting-guide.html
and provide commented, minimal, self-contained, reproducible code.
__
R-help@r-project.org mailing list
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PLEASE do read the posting guide http://www.R-project.org/posting-guide.html
and provide commented, minimal, self-contained, reproducible code.
Re: [R] The L Word
CB == Claudia Beleites cbelei...@units.it on Thu, 24 Feb 2011 12:31:55 +0100 writes: CB On 02/24/2011 11:20 AM, Prof Brian Ripley wrote: On Thu, 24 Feb 2011, Tal Galili wrote: Thank you all for the answers. So if I may extend on the question - When is it important to use 'Literal integer'? Under what situations could not using it cause problems? Is it a matter of efficiency or precision or both? Efficiency: it avoids unnecessary type conversions. For example length(x) 1 has to coerce the lhs to double. We have converted the base code to use integer constants because such small efficiency gains can add up. Integer vectors can be stored more compactly than doubles, but that is not going to help for length 1: object.size(1) 48 bytes object.size(1L) 48 bytes (32-bit system). CB see: CB n - 0L : 100L CB szi - sapply (n, function (n) object.size (integer (n))) CB szd - sapply (n, function (n) object.size (double (n))) CB plot (n, szd) CB points (n, szi, col = red) yes. Note however that I've never seen evidence for a *practical* difference in simple cases, and also of such cases as part of a larger computation. But I'm happy to see one if anyone has an interesting example. E.g., I would typically never use 0L:100L instead of 0:100 in an R script because I think code readability (and self explainability) is of considerable importance too. Martin __ R-help@r-project.org mailing list https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide http://www.R-project.org/posting-guide.html and provide commented, minimal, self-contained, reproducible code.
Re: [R] The L Word
Note however that I've never seen evidence for a *practical* difference in simple cases, and also of such cases as part of a larger computation. But I'm happy to see one if anyone has an interesting example. E.g., I would typically never use 0L:100L instead of 0:100 in an R script because I think code readability (and self explainability) is of considerable importance too. But : casts to integer anyway: str(0:100) int [1:101] 0 1 2 3 4 5 6 7 8 9 ... And performance in this case is (obviously) negligible: library(microbenchmark) microbenchmark(as.integer(c(0, 100)), times = 1000) Unit: nanoeconds min lq median uq max as.integer(c(0, 100)) 712 791813 896 15840 (mainly included as opportunity to try out microbenchmark) So you save ~800 ns but typing two letters probably takes 0.2 s (100 wpm, ~ 5 letters per word + space = 0.1s per letter), so it only saves you time if you're going to be calling it more than 125000 times ;) Hadley -- Assistant Professor / Dobelman Family Junior Chair Department of Statistics / Rice University http://had.co.nz/ __ R-help@r-project.org mailing list https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide http://www.R-project.org/posting-guide.html and provide commented, minimal, self-contained, reproducible code.
Re: [R] The L Word
HW == Hadley Wickham had...@rice.edu
on Thu, 24 Feb 2011 10:14:35 -0600 writes:
Note however that I've never seen evidence for a *practical*
difference in simple cases, and also of such cases as part of a
larger computation.
But I'm happy to see one if anyone has an interesting example.
E.g., I would typically never use 0L:100L instead of 0:100
in an R script because I think code readability (and self
explainability) is of considerable importance too.
HW But : casts to integer anyway:
str(0:100)
HW int [1:101] 0 1 2 3 4 5 6 7 8 9 ...
Sure !! I've been the one who had use 0:0 or 1:1
in those rare cases integers where required (e.g. in .C(..)),
before the L word existed.
HW And performance in this case is (obviously) negligible:
library(microbenchmark)
microbenchmark(as.integer(c(0, 100)), times = 1000)
HW Unit: nanoeconds
HW min lq median uq max
HW as.integer(c(0, 100)) 712 791813 896 15840
HW (mainly included as opportunity to try out microbenchmark)
??
Thanks! Did not know it.
*HOWEVER* the above as.integer(c(0,100))
is of course *much more* than what is internally needed to cast
the two doubles to integer.
Try this a few times ... and wonder :
boxplot(mb2 - microbenchmark(L = 1L:100L, 1:100, times=5000), notch=TRUE)
mb2
Unit: nanoeconds
min lq median uq max
L 316 410472 555 6843
1:100 311 393440 497 7309
the result (on my 64-bit linux) seems to indicate that 1L:100L
takes even slightly (but significantly [notches]) longer.
However, using
boxplot(mb - microbenchmark(1:100, L = 1L:100L, times=5000), notch=TRUE)
mb
Unit: nanoeconds
min lq median uq max
1:100 296 401469 550 9426
L 313 396438 496 16525
is less conclusive..
so, actually this is exactly one of those cases
I do *not* see a difference, even if I look very hard.
{ BTW: There's at least one (if not two) buglet in 'microbenchmark'
which I evaded using L = above :
1) It should not use as.character(exprs)
but rather unlist(lapply(exprs, deparse))
2) boxplot.microbenchmark should probably be more careful for
the case when two rows have the same name (as it happens if
I leave away L = above)
}
Martin
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Re: [R] The L Word
MM == Martin Maechler maech...@stat.math.ethz.ch
on Thu, 24 Feb 2011 18:34:36 +0100 writes:
HW == Hadley Wickham had...@rice.edu
on Thu, 24 Feb 2011 10:14:35 -0600 writes:
Note however that I've never seen evidence for a *practical*
difference in simple cases, and also of such cases as part of
a larger computation. But I'm happy to see one if anyone has
an interesting example.
E.g., I would typically never use 0L:100L instead of 0:100
in an R script because I think code readability (and self
explainability) is of considerable importance too.
HW But : casts to integer anyway:
str(0:100)
HW int [1:101] 0 1 2 3 4 5 6 7 8 9 ...
MM Sure !! I've been the one who had use 0:0 or 1:1
MM in those rare cases integers where required (e.g. in .C(..)),
MM before the L word existed.
HW And performance in this case is (obviously) negligible:
library(microbenchmark)
microbenchmark(as.integer(c(0, 100)), times = 1000)
HW Unit: nanoeconds
HW min lq median uq max
HW as.integer(c(0, 100)) 712 791813 896 15840
HW (mainly included as opportunity to try out microbenchmark)
MM ??
MM Thanks! Did not know it.
MM *HOWEVER* the above as.integer(c(0,100)) is of course
MM *much more* than what is internally needed to cast
MM the two doubles to integer.
MM Try this a few times ... and wonder :
MM boxplot(mb2 - microbenchmark(L = 1L:100L, 1:100, times=5000),
notch=TRUE
mb2
MM Unit: nanoeconds
MM min lq median uq max
MM L 316 410472 555 6843
MM 1:100 311 393440 497 7309
MM the result (on my 64-bit linux) seems to indicate that 1L:100L
MM takes even slightly (but significantly [notches]) longer.
MM However, using
MM boxplot(mb - microbenchmark(1:100, L = 1L:100L, times=5000),
notch=TRUE)
mb
MM Unit: nanoeconds
MM min lq median uq max
MM 1:100 296 401469 550 9426
MM L 313 396438 496 16525
MM is less conclusive..
MM so, actually this is exactly one of those cases
MM I do *not* see a difference, even if I look very hard.
MM { BTW: There's at least one (if not two) buglet in
MM'microbenchmark' which I evaded using L = above :
MM 1) It should not use as.character(exprs)
MM but rather unlist(lapply(exprs, deparse))
MM 2) boxplot.microbenchmark should probably be more careful for
MM the case when two rows have the same name (as it happens if
MM I leave away L = above)
MM }
and I forgot the buglet in print.microbenchmark which says
nanoeconds (missing s).
BTW: Another -- more realistic example where I can't see any
advantage of using L is x[1L] vs x[1] :
str(x - 0 + 1:100)
num [1:100] 1 2 3 4 5 6 7 8 9 10 ...
t. - microbenchmark(x[1], times=5000)
tL - microbenchmark(x[1L], times=5000)
t.
Unit: nanoeconds
min lq median uq max
x[1] 198 208 241.5 299 4843
tL
Unit: nanoeconds
min lq median uq max
x[1] 194 208234 296 6304
so the noise is much much larger than a noticable difference.
Martin
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Re: [R] The L Word
-Original Message-
From: r-help-boun...@r-project.org
[mailto:r-help-boun...@r-project.org] On Behalf Of Martin Maechler
Sent: Thursday, February 24, 2011 7:45 AM
To: Claudia Beleites
Cc: r-help@r-project.org
Subject: Re: [R] The L Word
CB == Claudia Beleites cbelei...@units.it
on Thu, 24 Feb 2011 12:31:55 +0100 writes:
CB On 02/24/2011 11:20 AM, Prof Brian Ripley wrote:
On Thu, 24 Feb 2011, Tal Galili wrote:
Thank you all for the answers.
So if I may extend on the question -
When is it important to use 'Literal integer'?
Under what situations could not using it cause problems?
Is it a matter of efficiency or precision or both?
Efficiency: it avoids unnecessary type conversions. For example
length(x) 1
has to coerce the lhs to double. We have converted the base
code to use integer constants because such small efficiency
gains can add up.
Integer vectors can be stored more compactly than doubles, but
that is not going to help for length 1:
object.size(1)
48 bytes
object.size(1L)
48 bytes
(32-bit system).
CB see:
CB n - 0L : 100L
CB szi - sapply (n, function (n) object.size (integer (n)))
CB szd - sapply (n, function (n) object.size (double (n)))
CB plot (n, szd)
CB points (n, szi, col = red)
yes.
Note however that I've never seen evidence for a *practical*
difference in simple cases, and also of such cases as part of a
larger computation.
But I'm happy to see one if anyone has an interesting example.
I don't know how interesting this example is, but I use digitsL
when combining a scalar with what I know is an integer vector so
I don't unnecessarily change its type. Also, if I have a function
that returns an integer vector in general cases but a special value
like NA or -1 in unusual cases, I would use NA_integer_ or -1L for those
special cases so the function returns the same class of data in
all cases. These things can be important when trying to write a
faster/better version of a builtin function, where I
want to make the new output exactly match the original.
E.g., here is a function that does exactly what sequence() does
but is about 10 times faster for long input vectors (say
seq_len(1e6)%%4L):
Sequence.L - function (nvec)
{
seq_len(sum(nvec)) - rep(cumsum(c(0L, nvec[-length(nvec)])), nvec)
}
If I change the 0L to 0.0 (or 0) then its result is no longer identical
to sequence's result.
(If I were designing a new data analysis language from scratch, I'd
be tempted to omit the integer type and make all numbers 64-bit doubles,
logicals 1 byte or 2 bit things, and maybe throw in some integral
types for image processing but not for general use. 32-bit integers
are pretty limiting.)
Bill Dunlap
Spotfire, TIBCO Software
wdunlap tibco.com
E.g., I would typically never use 0L:100L instead of 0:100
in an R script because I think code readability (and self
explainability) is of considerable importance too.
Martin
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and provide commented, minimal, self-contained, reproducible code.
Re: [R] The L Word
On 02/24/2011 05:14 PM, Hadley Wickham wrote: Note however that I've never seen evidence for a *practical* difference in simple cases, and also of such cases as part of a larger computation. But I'm happy to see one if anyone has an interesting example. E.g., I would typically never use 0L:100L instead of 0:100 in an R script because I think code readability (and self explainability) is of considerable importance too. But : casts to integer anyway: I know - I just thought that on _this_ thread I ought to write it with L ;-) and I don't think I write 1L : 100L in real life. I use the L far more often as a reminder than for performance. Particularly in function definitions. str(0:100) int [1:101] 0 1 2 3 4 5 6 7 8 9 ... And performance in this case is (obviously) negligible: library(microbenchmark) microbenchmark(as.integer(c(0, 100)), times = 1000) Unit: nanoeconds min lq median uq max as.integer(c(0, 100)) 712 791813 896 15840 (mainly included as opportunity to try out microbenchmark) So you save ~800 ns but typing two letters probably takes 0.2 s (100 wpm, ~ 5 letters per word + space = 0.1s per letter), so it only saves you time if you're going to be calling it more than 125000 times ;) calling 125000 times happens in my real life. I have e.g. one data set with 2e5 spectra (and another batch of that size waiting for me), so anything done for each spectrum reaches this number each time the function is needed. Also of course, the conversion time goes with the length of the vector. On the other hand, in 95 % of the cases taking an hour to think about the algorithm will have much larger effects ;-). Also, I notice that the first few measures of microbenchmark are often much longer (for fast operations). Which may just indicate that the total speed depends much more on whether the code allows caching or not. And that may mean that any such coding details may or may not help at all: A single such conversion may take disproportionally much more time. I just (yesterday) came across a situation where the difference between numeric and integer does matter (considering that I do that with ≈ 3e4 x 125 x 6 array size): as.factor microbenchmark (i = as.factor (1:1e3), d = as.factor ((1:1e3)+0.0)) Unit: nanoeconds min lq median uq max i 884039 891106 895847 901630 2524877 d 2698637 2770936 2778271 2807572 4266197 but then: microbenchmark ( sd = structure ((1:1e3)+0.0, .Label = 1:100, class = factor), si = structure ((1:1e3)+0L, .Label = 1:100, class = factor)) Unit: nanoeconds min lq median uq max sd 52875 53615 54040 54448 1385422 si 45904 46936 47332 47778 65360 Cheers, Claudia -- Claudia Beleites Dipartimento dei Materiali e delle Risorse Naturali Università degli Studi di Trieste Via Alfonso Valerio 6/a I-34127 Trieste phone: +39 0 40 5 58-37 68 email: cbelei...@units.it __ R-help@r-project.org mailing list https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide http://www.R-project.org/posting-guide.html and provide commented, minimal, self-contained, reproducible code.
[R] The L Word
I've been wondering what L means in the R computing context, and was
wondering if someone could point me to a reference where I could read about
it, or tell me what it's called so that I can search for it myself. (L by
itself is a little too general for a search term).
I encounter it in strange places, most recently in the save documentation.
save(..., list = character(0L),
file = stop('file' must be specified),
ascii = FALSE, version = NULL, envir = parent.frame(),
compress = !ascii, compression_level,
eval.promises = TRUE, precheck = TRUE)
I remember that you can also find it when you step inside an apply function:
sapply(1:10, function(x)browser())
Called from: FUN(1:10[[1L]], ...)
I apologize for being vague, it's just something that I would like to
understand about the R language (the R word).
Thank you!
Gene
[[alternative HTML version deleted]]
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Re: [R] The L Word
Gene, it's described in ?NumericConstants
HTH, Erik
Gene Leynes wrote:
I've been wondering what L means in the R computing context, and was
wondering if someone could point me to a reference where I could read about
it, or tell me what it's called so that I can search for it myself. (L by
itself is a little too general for a search term).
I encounter it in strange places, most recently in the save documentation.
save(..., list = character(0L),
file = stop('file' must be specified),
ascii = FALSE, version = NULL, envir = parent.frame(),
compress = !ascii, compression_level,
eval.promises = TRUE, precheck = TRUE)
I remember that you can also find it when you step inside an apply function:
sapply(1:10, function(x)browser())
Called from: FUN(1:10[[1L]], ...)
I apologize for being vague, it's just something that I would like to
understand about the R language (the R word).
Thank you!
Gene
[[alternative HTML version deleted]]
__
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https://stat.ethz.ch/mailman/listinfo/r-help
PLEASE do read the posting guide http://www.R-project.org/posting-guide.html
and provide commented, minimal, self-contained, reproducible code.
__
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PLEASE do read the posting guide http://www.R-project.org/posting-guide.html
and provide commented, minimal, self-contained, reproducible code.
Re: [R] The L Word
On 02/23/2011 05:08 PM, Gene Leynes wrote:
I've been wondering what L means in the R computing context, and was
wondering if someone could point me to a reference where I could read about
it, or tell me what it's called so that I can search for it myself. (L by
itself is a little too general for a search term).
It means that the number is an integer (a _L_ong integer of 32 bit actually)
I encounter it in strange places, most recently in the save documentation.
save(..., list = character(0L),
file = stop('file' must be specified),
ascii = FALSE, version = NULL, envir = parent.frame(),
compress = !ascii, compression_level,
eval.promises = TRUE, precheck = TRUE)
I remember that you can also find it when you step inside an apply function:
sapply(1:10, function(x)browser())
Called from: FUN(1:10[[1L]], ...)
I apologize for being vague, it's just something that I would like to
understand about the R language (the R word).
Thank you!
Gene
[[alternative HTML version deleted]]
__
R-help@r-project.org mailing list
https://stat.ethz.ch/mailman/listinfo/r-help
PLEASE do read the posting guide http://www.R-project.org/posting-guide.html
and provide commented, minimal, self-contained, reproducible code.
--
Claudia Beleites
Dipartimento dei Materiali e delle Risorse Naturali
Università degli Studi di Trieste
Via Alfonso Valerio 6/a
I-34127 Trieste
phone: +39 0 40 5 58-37 68
email: cbelei...@units.it
__
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PLEASE do read the posting guide http://www.R-project.org/posting-guide.html
and provide commented, minimal, self-contained, reproducible code.
Re: [R] The L Word
Hi Gene,
It means 'Literal integer'.
So 1L is a proper integer 1, and 0L is a proper integer 0.
Hope it helps,
Tsjerk
On Wed, Feb 23, 2011 at 5:08 PM, Gene Leynes gleyne...@gmail.com wrote:
I've been wondering what L means in the R computing context, and was
wondering if someone could point me to a reference where I could read about
it, or tell me what it's called so that I can search for it myself. (L by
itself is a little too general for a search term).
I encounter it in strange places, most recently in the save documentation.
save(..., list = character(0L),
file = stop('file' must be specified),
ascii = FALSE, version = NULL, envir = parent.frame(),
compress = !ascii, compression_level,
eval.promises = TRUE, precheck = TRUE)
I remember that you can also find it when you step inside an apply function:
sapply(1:10, function(x)browser())
Called from: FUN(1:10[[1L]], ...)
I apologize for being vague, it's just something that I would like to
understand about the R language (the R word).
Thank you!
Gene
[[alternative HTML version deleted]]
__
R-help@r-project.org mailing list
https://stat.ethz.ch/mailman/listinfo/r-help
PLEASE do read the posting guide http://www.R-project.org/posting-guide.html
and provide commented, minimal, self-contained, reproducible code.
--
Tsjerk A. Wassenaar, Ph.D.
post-doctoral researcher
Molecular Dynamics Group
* Groningen Institute for Biomolecular Research and Biotechnology
* Zernike Institute for Advanced Materials
University of Groningen
The Netherlands
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and provide commented, minimal, self-contained, reproducible code.
Re: [R] The L Word
The notation '1L' mean to interprete the data as an 'integer'.
str(1)
num 1
str(1L)
int 1
str(0xaa)
num 170
str(0xaaL)
int 170
On Wed, Feb 23, 2011 at 11:08 AM, Gene Leynes gleyne...@gmail.com wrote:
I've been wondering what L means in the R computing context, and was
wondering if someone could point me to a reference where I could read about
it, or tell me what it's called so that I can search for it myself. (L by
itself is a little too general for a search term).
I encounter it in strange places, most recently in the save documentation.
save(..., list = character(0L),
file = stop('file' must be specified),
ascii = FALSE, version = NULL, envir = parent.frame(),
compress = !ascii, compression_level,
eval.promises = TRUE, precheck = TRUE)
I remember that you can also find it when you step inside an apply function:
sapply(1:10, function(x)browser())
Called from: FUN(1:10[[1L]], ...)
I apologize for being vague, it's just something that I would like to
understand about the R language (the R word).
Thank you!
Gene
[[alternative HTML version deleted]]
__
R-help@r-project.org mailing list
https://stat.ethz.ch/mailman/listinfo/r-help
PLEASE do read the posting guide http://www.R-project.org/posting-guide.html
and provide commented, minimal, self-contained, reproducible code.
--
Jim Holtman
Data Munger Guru
What is the problem that you are trying to solve?
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Re: [R] The L Word
Thank you everyone, that makes a lot more sense now. It's not at all what I
would have guessed! (I thought that it might have to do with scope)
It's one of those little things would add just enough confusion that I would
sort of tune out whenever I saw it. So, I really appreciate having this
little additional nugget of understanding.
On Wed, Feb 23, 2011 at 10:14 AM, Claudia Beleites cbelei...@units.itwrote:
On 02/23/2011 05:08 PM, Gene Leynes wrote:
I've been wondering what L means in the R computing context, and was
wondering if someone could point me to a reference where I could read
about
it, or tell me what it's called so that I can search for it myself. (L by
itself is a little too general for a search term).
It means that the number is an integer (a _L_ong integer of 32 bit
actually)
I encounter it in strange places, most recently in the save
documentation.
save(..., list = character(0L),
file = stop('file' must be specified),
ascii = FALSE, version = NULL, envir = parent.frame(),
compress = !ascii, compression_level,
eval.promises = TRUE, precheck = TRUE)
I remember that you can also find it when you step inside an apply
function:
sapply(1:10, function(x)browser())
Called from: FUN(1:10[[1L]], ...)
I apologize for being vague, it's just something that I would like to
understand about the R language (the R word).
Thank you!
Gene
[[alternative HTML version deleted]]
__
R-help@r-project.org mailing list
https://stat.ethz.ch/mailman/listinfo/r-help
PLEASE do read the posting guide
http://www.R-project.org/posting-guide.html
and provide commented, minimal, self-contained, reproducible code.
--
Claudia Beleites
Dipartimento dei Materiali e delle Risorse Naturali
Università degli Studi di Trieste
Via Alfonso Valerio 6/a
I-34127 Trieste
phone: +39 0 40 5 58-37 68
email: cbelei...@units.it
__
R-help@r-project.org mailing list
https://stat.ethz.ch/mailman/listinfo/r-help
PLEASE do read the posting guide
http://www.R-project.org/posting-guide.html
and provide commented, minimal, self-contained, reproducible code.
[[alternative HTML version deleted]]
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and provide commented, minimal, self-contained, reproducible code.
