Displaying 20 results from an estimated 6000 matches similar to: "diff, POSIXct, POSIXlt, POSIXt"
2010 May 20
1
Strange behaviour when using diff with POSIXt and POSIXlt objects
Dear list,
I´m calculating time differences between series of time stamps and I noticed
something odd:
If I do this...
> time1=strptime("2009 05 31 22 57 00",format="%Y %m %d %H %M")
> time2=strptime("2009 05 31 23 07 00",format="%Y %m %d %H %M")
>
> diff(c(time1,time2),units="mins")
Time difference of 10 mins
.. I get the correct
2006 Oct 21
1
plot.POSIXct plot.POSIXlt
Hi,
Just to signal that when I want to plot POSIXct variable on x using
format within plot(), I get what I want on the plot but with a number of
warnings:
> plot(y~x,format="%y-%m")
Warning messages:
1: "format" is not a graphical parameter in: plot.window(xlim, ylim,
log, asp, ...)
2: "format" is not a graphical parameter in: plot.xy(xy, type, pch, lty,
2011 Feb 18
1
problem with rbind when data frame contains an date-time variable "POSIXt" "POSIXlt"
I'm trying to rbind two data frames, both with the same columns names. One
of the columns is a variable with date-time and this variable is causing the
rbind to fail--giving the error
"Error in names(value[[jj]])[ri] <- nm : 'names' attribute [7568] must be
the same length as the vector [9]"
Is there a way to stack or rbind these two data frames even with this
extended
2012 Feb 24
6
strange behaviour of "POSIXlt" "POSIXt" object
Hi,
Does anybody know why get I this kind of strange situation:
Browse[2]> hcEnd
[1] "2009-03-29 06:30:00"
Browse[2]> class(hcEnd)
[1] "POSIXlt" "POSIXt"
Browse[2]> is.na(hcEnd)
[1] TRUE
This issue is the source of my all issues in my program,
Thanks for your help
--
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2011 Mar 08
1
Date arithmetic coerces POSIXlt to POSIXct?
Hi. This feels like a bug to me, or at least an undocumented feature,
but I thought I'd see what people here thought of it. Consider a POSIXlt
object like this one:
> a <- as.POSIXlt ("2011-01-23 12:45:45")
> class (a)
[1] "POSIXlt" "POSIXt"
Fine. Now, if I do some arithmetic on that object, the result is
converted to POSIXct.
> class (a
2010 Oct 28
1
Unexpected behabiour of min, tapply and POSIXct/POSIXlt classes?
Hello,
I found rather surprising the behaviour of POSIXct and POSIXlt classes
when combined with min and tapply.
The details can be deduced from the script below:
############# Start of the script ####################
before <- Sys.time()
Sys.sleep( 1 )
now1 <- now2 <- Sys.time()
my.times <- c( before, now1, now2 )
class( my.times ) ## [1] "POSIXct"
2006 Nov 09
1
POSIXlt converted to POSIXct in as.data.frame()
In trying to use as.Date(), I've come across the conversion of POSIXlt to
POSIXct when a POSIXlt variable is included in a data frame:
my_POSIX <- strptime(c("11-09-2006", "11-10-2006", "11-11-2006",
"11-12-2006", "11-13-2006"), "%m-%d-%Y")
str(my_POSIX)
my_Date <- as.Date(my_POSIX)
str(my_Date)
data <- format(my_Date)
2005 Jul 19
2
Problems with date-format (R 2.1.1 + chron)
Hello,
today I've updated on the newest R-Version. But sadly a function I needed
didnt want to work:
The input is e.g.
days(as.Date("21-07-2005","%d-%m-%y"))
the error is: Fehler in Math.Date(dts): floor nicht definiert f??r Date
Objekte
(Error in Math.Date(dts): floor not defined for date objects)
Same for year. Only months gives me the correct output.
In Version
2011 Aug 30
3
having trouble extracting week from chron object
Running R 2.13.1 on Windows XP.
I would like to get week of the year (1-52) for each date.
library(chron)
dts <- dates(c("02/27/92", "02/27/92", "01/14/92","02/28/92", "02/01/92"))
dts
dts.chron <- as.chron(dts)
dts.chron
class(dts.chron)
# all of these component extractions work:
months(dts.chron)
weekdays(dts.chron)
years(dts.chron)
2005 Apr 15
2
aggregate slow with variables of type 'dates' - how to solve
Dear all
I use aggregate with variables of type numeric and dates. For type numeric
functions, such as sum() are very fast, but similar simple functions, such
as min() are much slower for the variables of type 'dates'. The difference
gets bigger the larger the 'id' var is - but see this sample code:
dts <- dates(c("02/27/92", "02/27/92",
2012 Mar 28
1
POSIXlt vs POSIXct
Hello R users
I am searching for a descriptive summary of the use of POSIXlt as
compared to POSIXct date/time formats. I have been using them
extensively for different purposes, but still can't quite understand
when to use which one for the most efficient coding and use. I typically
use them in graphics, comparison of times, interpolation of values
between times, computation of
2007 Aug 08
2
Error: Cannot Coerce POSIXt to POSIXct when building package
A newbie here - please forgive me if this is a basic question. We have an
in house package built in R 2.2.1 (yes we're a little behind the times at
our firm)and would like to rebuild it using R 2.5.1. However, when I try
and build the package from source, I keep getting this error:
Error in as(slotVal, slotClass, strict = FALSE) :
no method or default for coercing "POSIXt"
2003 Aug 04
0
as.POSIXct Bug when used with POSIXlt arg and tz= arg (PR#3646)
Tracking down this bug was joint work with Jermoe Asselin (jerome at
hivnet.ubc.ca) and Patrick Connolly (p.connolly at hortresearch.co.nz). We
collectively were able to determine that this is a problem in both Windows 2000
and in Linux and by testing it in our three time zones that it seems to be
daylight savings time related.
Conversion of POSIXlt datetimes to POSIXct appears to have problems.
2008 Mar 26
0
as.POSIXct/as.POSIXlt generics
Hi,
I am trying to define the as.POSIXct as an S4 method for one of my
classes. Trying to define a generic, I am getting an error that it is
already differently defined in base. However, if I query for it, there
is no definition. Being in base, I also cannot really import it. If I
define methods without definig a generic, they will work but with a
warning that a new generic will be automatically
2012 Sep 20
1
[PATCH v2] arm: introduce a DTS for Xen unprivileged virtual machines
Given that the xenvm machine is based on vexpress but with an extremely
limited selection of peripherals (the guest is supposed to use virtual
devices instead), add "xen,xenvm" to the list of compatible machines in
mach-vexpress.
Changes in v2:
- remove include skeleton;
- use #address-cells = <2> and #size-cells = <2>;
- remove the debug bootargs;
- use memory@80000000
2009 Feb 27
0
POSIXlt, POSIXct, strptime, GMT and 1969-12-31 23:59:59
R-devel:
Some very inconsistent behavior, that I can't seem to find documented.
Sys.setenv(TZ="GMT")
str(unclass(strptime("1969-12-31 23:59:59","%Y-%m-%d %H:%M:%S")))
List of 9
$ sec : num 59
$ min : int 59
$ hour : int 23
$ mday : int 31
$ mon : int 11
$ year : int 69
$ wday : int 3
$ yday : int 364
$ isdst: int 0
- attr(*, "tzone")= chr
2006 Sep 01
3
Date conversion with as.POSIXct and as.POSIXlt (PR#9196)
Full_Name: Erich Neuwirth
Version: 2.3.1
OS: Windows XP, Linux
Submission from: (NULL) (131.130.135.167)
Converting Sys.Date() to a POSIX compliant time type in different ways
produces inconsistent results:
> Sys.date()
[1] "2006-09-01"
> as.POSIXct(Sys.Date())
[1] "2006-09-01 02:00:00 CEST"
> as.POSIXlt(Sys.Date())
[1] "2006-09-01"
>
2019 Aug 02
0
Infrequent but steady NULL-pointer caused segfault in as.POSIXlt.POSIXct (R 3.4.4)
In an optimized build, debug info is just an approximation. It might
help to debug in a build of R and packages without compiler
optimizations (-O0), where the debug information is accurate. However,
first I would try to modify the example to trigger more often, or try to
find external ways to make it trigger more often (e.g. via gctorture).
Then I would try to make the example smaller (not
2014 Sep 25
3
[5/5] ARM: tegra: jetson-tk1: enable GK20A GPU
Playing a bit with todays linux-next on my jetson, it seems this patch is
still required for enabling the GPU. Is there anything blocking it (firmware
not available yet in liux-firmware?)
On Mon, May 19, 2014 at 06:24:10PM +0900, Alexandre Courbot wrote:
> Signed-off-by: Alexandre Courbot <acourbot at nvidia.com>
> ---
> arch/arm/boot/dts/tegra124-jetson-tk1.dts | 8 +++++++-
>
2006 Dec 07
2
Matplot does not work with x being POSIXt class (PR#9412)
Hi,
Matplot works with x being Date class but not POSIXt. Here is the
example with R version 2.5.0 Under development (unstable) (2006-12-06
r40129)
Example:
x <- Sys.Date() - c(1:10)
y <- cbind(1:10, 10:1)
class(x)
## [1] "Date"
matplot(x, y)
x <- strptime(as.character(x), format="%Y-%m-%d")
## [1] "POSIXt" "POSIXlt"
matplot(x, y)
Error in