Displaying 20 results from an estimated 1000 matches similar to: "time question"
2024 Oct 10
1
Typo in DateTimeClasses.Rd
Hello,
When following a thread that started today [1], I read the documentation
for DateTimeClasses {base} more carefully and noticed a typo in the
"Details on POSIXlt" section, in the paragraph right after the
components list.
The original and corrected are "he" instead of "the".
From earlier versions of R, he last two components will not be present
for
2002 Feb 13
2
formatting date strings
Hi all
I am a relatively new R user so please excuse this question if it has been
covered some where else, just tell me where to find it.
I have a simulation model that out puts dates in a standard dd/mm/yy format
R reads this as a factor and I cant find anything that will allow me to
convert them to a date. In S+ I have used a chron() function that required
you to specify the format of the
2005 Nov 23
3
date/time arithmetic
On the help page "DateTimeClasses {base}" it says:
"One can add or subtract a number of seconds or a difftime object
from a date-time object, but not add two date-time objects."
However,
> x<-Sys.time(); y<-Sys.time()+3600
> diff<-y-x
> x; y; diff
[1] "2005-11-23 19:58:20 GMT"
[1] "2005-11-23 20:58:20 GMT"
Time difference of 1 hours
2005 Jan 31
4
aggregating dates
I have a frame which contains 3 columns:
"date" "defectnum" "state"
And I want to get the most recent state change for a given defect number. date is POSIXct.
I have tried:
aggregate(ev$date, by=list(ev$defectnum), max)
Which appears to be working except that the dates seem to come back as integers (presumably the internal representation of POSIXct).
When I
2007 Jan 04
2
Seek general information about time/date storage and functions in R
Hello R List -
I have to import Excel files (either as .csv files or using RODBC) into
R (2.4.1, Windows) and operate on dates and times (e.g. find minutes
between times, change dates to days of week or analyze by weeks of
year). The help files for format.Date, strptime, as.POSIX,
DateTimeClasses, etc. etc. are informative but perhaps a little terse.
I have googled unsuccessfully for a more
2010 Jan 14
3
Barchart bar lengths not proportionate
When I use barchart (with default formatting options), I get bars whose
lengths/heights are not proportional to their value. For example:
http://drop.io/wbagm6s/asset/capture-png
Many of the values in this chart are 1; however, because the blue bars
extend to the left of the "0" tick mark, those bars appear to represent
higher numeric values. Is there a way to make the length of the
2004 Mar 01
6
Find out the day of week for a chron object?
I know that this is correct:
library(chron)
x = dates("01-03-04", format="d-m-y", out.format="day mon year")
print(x)
It gives me the string "01 Mar 2004" which is correct.
I also know that I can say:
print(day.of.week(3,1,2004))
in which case he says 1, for today is monday.
My question is: How do I combine these two!? :-) I have a
2020 Apr 04
5
Help useRs to use R's own Time/Date objects more efficiently
This is mostly a RFC [but *not* about the many extra packages, please..]:
Noticing to my chagrin how my students work in a project,
googling for R code and cut'n'pasting stuff together, accumulating
this and that package on the way all just for simple daily time series
(though with partly missing parts),
using chron, zoo, lubridate, ... all for things that are very
easy in base R *IF*
2009 May 20
2
Class for time of day?
What is the recommended class for time of day (independent of calendar
date)?
And what is the recommended way to get the time of day from a POSIXct
object? (Not a string representation, but a computable representation.)
I have looked in the man page for DateTimeClasses, in the Time Series
Analysis Task View and in Spector's Data Manipulation book but haven't found
these. Clearly I can
2012 Dec 06
1
Incorrect DST time changes in DateTimeClasses
Can anyone please shed any light on why R DateTimeClasses give weird times for when daylight saving time information changes, and which aren't consistent with the OS?
Example:
Expected result: in New Zealand DST stopped (NZDT -> NZST) at 03:00 NZDT on 2010-04-04, as confirmed by the OS time zone info (OS X 10.8.2):
zdump -v /etc/localtime
/etc/localtime Sat Apr 3 13:59:59 2010 UTC
2020 Apr 06
2
Help useRs to use R's own Time/Date objects more efficiently
> (1) Create a top-level help page with a title like "Date and Time
> Classes" to give a brief but general overview. This would mean the
> existing DateTimeClasses would need a new title.
I wanted to modify my first suggestion.
Perhaps a better idea would be to reference an external document
giving an overview of the subject.
I couldn't find a discussion of POSIXct/POSIXlt
2009 Jul 24
3
str(data.frame) after subsetting reflects original structure, not subsetted structure?
I find that after subsetting (you may prefer "conditional selection") a data
frame and assigning it to a new object, the str(new object) reflects the
original data frame, not the new one:
A <- rnorm(20)
B <- factor(rep(c("t", "g"), 10))
C <- factor(rep(c("h", "l"), 10))
D <- data.frame(A, B, C)
str(D) # reports correctly
E <-
2015 Aug 31
4
Classic upgrade - no email addresses
Hi Rowland,
Perhaps I misled you with my wording. Each user has just one email
address, which was not migrated across. From where I'm sitting that
looks like a very serious bug.
regards,
John
On 31/08/15 19:07, Rowland Penny wrote:
> On 31/08/15 07:27, John Gardeniers wrote:
>> I've been running through a bunch of tests after migrating from
>> Samba > 3 to Samba 4
2007 Mar 19
3
R4.1: seq.POSIXt, tz="AEST" (PR#9572)
Times from seq.POSIXt come out wrong in AEST timezone around Feb 29 every
leap year before 1970 (on Windows XP).
According to help(DateTimeClasses), this is handled by "our own C code".
> x <- as.POSIXct("1968-02-27") # tz="AEST"
> x.gmt <- as.POSIXct("1968-02-27", tz="GMT")
> data.frame(
GMT=seq(x.gmt, by="day",
2011 Oct 05
2
any way to convert back to DateTime class when "accidental" conversion to numeric?
Hi,
In short, I would like to know if there is any way to convert a numeric
into a date, similar to how strptime() can convert a string to a date time
class?
There are some functions, etc. which don't work well with dates, and
tend to force them into numerics. I understand that the number it spits
back is the number of seconds since the beginning of 1970 (see the first few
sentences
2007 Apr 12
3
Sharing trunks between asterisk machines
Hello eveybody,
I've been looking for a way to share trunks between two asterisk
servers. I guest I have to use Dundi, but I've not found the exact
method yet. I need a way to allow users registered in one server to
use the another server's trunks in the case the first server's trunks
were busy and vice versa. Is this possible?
Thank you so much, any comment will be useful.
2003 Dec 04
5
Processing calendar dates with R
I am a beginner in R with a background in SAS.
Are there built-in R methods of reading dates for calculating elapsed days
between two calendar dates? If so, are there any examples I can browse?
Thanks in anticipation.
John Byrne.
Lecturer in Information Systems.
Australian Catholic University.
2013 Nov 14
33
VCPUOP_set_periodic_timer
Hi all,
I need a periodic timer running at ideally at 125 microseconds and at
least 500 microseconds. I''ve just found the VCPUOP_set_periodic_timer,
however there is a comment saying "periods less than one millisecond may
not be supported".
I will be running on an x64 machine. Is this supported? If not, is there
any alternate means of generating a fast interrupt?
Regards.
2013 Aug 28
2
[PATCH] percpu ida: Switch to cpumask_t, add some comments
On Wed, 28 Aug 2013 14:00:10 -0700 Kent Overstreet <kmo at daterainc.com> wrote:
> On Wed, Aug 28, 2013 at 01:25:50PM -0700, Andrew Morton wrote:
> > On Wed, 28 Aug 2013 12:55:17 -0700 Kent Overstreet <kmo at daterainc.com> wrote:
> >
> > > Fixup patch, addressing Andrew's review feedback:
> >
> > Looks reasonable.
> >
> > >
2013 Aug 28
2
[PATCH] percpu ida: Switch to cpumask_t, add some comments
On Wed, 28 Aug 2013 14:00:10 -0700 Kent Overstreet <kmo at daterainc.com> wrote:
> On Wed, Aug 28, 2013 at 01:25:50PM -0700, Andrew Morton wrote:
> > On Wed, 28 Aug 2013 12:55:17 -0700 Kent Overstreet <kmo at daterainc.com> wrote:
> >
> > > Fixup patch, addressing Andrew's review feedback:
> >
> > Looks reasonable.
> >
> > >