[R] as.Date: fixed

Mon Apr 18 23:09:36 CEST 2016

Dear All,
Many thanks for bailing me out.
Ogbos
On Apr 18, 2016 9:07 PM, "David Winsemius" <dwinsemius at comcast.net> wrote:

>
> > On Apr 18, 2016, at 10:44 AM, Ogbos Okike <giftedlife2014 at gmail.com>
> wrote:
> >
> > Dear ALL,
> > Thank you so much for your contributions.
> > I have made some progress. Below is a simple script I gleaned from
> > your kind responses:
> > Sys.setenv(TZ="Etc/GMT")
> > dates <- c("02/27/92", "02/27/92", "01/14/92", "02/28/92", "02/01/92")
> >     times <- c("23:0:0", "22:0:0", "01:00:00", "18:0:0", "16:0:0")
> >     x <- paste(dates, times)
> >     aa<-strptime(x, "%m/%d/%y %H:%M:%S")
> > bb<-1:5
> > plot(aa, bb)
> >
> > I tried plotting my result and I got what I am looking for. I think I
> > am almost there.
> >
> > I am, however, stuck here. My data is a large file and the form
> > differs a little from the example I used. The quotation marks in both
> > date and time is my headache now. Such inverted commas are not in my
> > data. I can with awk transform my data to get exactly something like
> > dd/mm/yy. But I wont know how to make the data appear in quotation
> > mark in R.
>
> There are not any quotation marks in an R object that is displayed as
> "02/27/92". The quotation marks are just added by the print function to
> make it clear to the user that it is a character value.
>
> If you read such values in with read.table they would automatically be
> interpreted as character values and then converted to factor class (which
> you do not want). Read up on the use in the read.* functions for colClasses
> and stringsAsFactors to safely input character values.
> --
> David.
>
> > I will once more be glad for any more help.
> > Ogbos
> >
> > PS: I am still afraid of this forum. Please direct me to the right
> > forum if this is not ok. Thanks again.
> >
> >
> > On 4/18/16, peter dalgaard <pdalgd at gmail.com> wrote:
> >> The most important thing is that Date objects by definition do not
> include
> >> time of day. You want to look at ISOdatetime() and as.POSIXct()
> instead. And
> >> beware daylight savings time issues.
> >>
> >> -pd
> >>
> >> On 18 Apr 2016, at 15:09 , Ogbos Okike <giftedlife2014 at gmail.com>
> wrote:
> >>
> >>> Dear All,
> >>>
> >>> I have a data set containing year, month, day and counts as shown
> below:
> >>> data <- read.table("data.txt", col.names = c("year", "month", "day",
> >>> "counts"))
> >>> Using the formula below, I converted the data to as date and plotted.
> >>>
> >>> new.century <- data$year < 70
> >>>
> >>> data$year <- ifelse(new.century, data$year + 2000, data$year + 1900)
> >>>
> >>> data$date <- as.Date(ISOdate(data$year, data$month, data$day))
> >>>
> >>> The form of the data is:
> >>> 16 1 19 9078
> >>> 16 1 20 9060
> >>> 16 1 21 9090
> >>> 16 1 22 9080
> >>> 16 1 23 9121
> >>> 16 1 24 9199
> >>> 16 1 25 9289
> >>> 16 1 26 9285
> >>> 16 1 27 9245
> >>> 16 1 28 9223
> >>> 16 1 29 9298
> >>> 16 1 30 9327
> >>> 16 1 31 9365
> >>>
> >>> Now, I wish to include time (hour) in my data. The new data is of the
> >>> form:
> >>> 05 01 06 14    3849
> >>> 05 01 06 15    3845
> >>> 05 01 06 16    3836
> >>> 05 01 06 17    3847
> >>> 05 01 06 18    3850
> >>> 05 01 06 19    3872
> >>> 05 01 06 20    3849
> >>> 05 01 06 21    3860
> >>> 05 01 06 22    3868
> >>> 05 01 06 23    3853
> >>> 05 01 07 00    3839
> >>> 05 01 07 01    3842
> >>> 05 01 07 02    3843
> >>> 05 01 07 03    3865
> >>> 05 01 07 04    3879
> >>> 05 01 07 05    3876
> >>> 05 01 07 06    3867
> >>> 05 01 07 07    3887
> >>>
> >>> I now read the data as:
> >>> data <- read.table("data.txt", col.names = c("year", "month", "day",
> >>> "counts", "hour")) and also included hour in data$date <-
> >>> as.Date(ISOdate(data$year, data$month, data$day))
> >>> i.e data$date <- as.Date(ISOdate(data$year, data$month, data$day,
> >>> data$hour)).
> >>>
> >>> However, these did not work.
> >>>
> >>> Can you please assist be on how to get this date and time in the right
> >>> format. The right format I got without hour looks like : 2005-12-29"
> >>> "2005-12-29" "2005-12-29" "2005-12-29" "2005-12-29"
> >>> [8696] "2005-12-29" "2005-12-29" "2005-12-29" "2005-12-29" "2005-12-29"
> >>> [8701] "2005-12-29" "2005-12-29" "2005-12-29" "2005-12-29" "2005-12-29"
> >>> [8706] "2005-12-29" "2005-12-29" "2005-12-29" "2005-12-29" "2005-12-29"
> >>>
> >>> I used this in my plot. Please I want this format to include hour.
> >>>
> >>> Many thanks for your help. I am just a newbe. I am not sure if this
> >>> forum is the right one. After registration, I tried to post to Nabble
> >>> forum where I registered but could not succeed.
> >>>
> >>> If there is a mistake, please help/direct me to the right forum.
> >>>
> >>> Best regards
> >>> Ogbos
> >>>
> >>> ______________________________________________
> >>> R-help at r-project.org mailing list -- To UNSUBSCRIBE and more, see
> >>> 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.
> >>
> >> --
> >> Peter Dalgaard, Professor,
> >> Center for Statistics, Copenhagen Business School
> >> Solbjerg Plads 3, 2000 Frederiksberg, Denmark
> >> Phone: (+45)38153501
> >> Office: A 4.23
> >> Email: pd.mes at cbs.dk  Priv: PDalgd at gmail.com
> >>
> >>
> >
> > ______________________________________________
> > R-help at r-project.org mailing list -- To UNSUBSCRIBE and more, see
> > 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.
>
> David Winsemius
> Alameda, CA, USA
>
>

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