Yes, thank you so much.

Stefano

         (oo)
--oOO--( )--OOo----------------
Stefano Sofia PhD
Civil Protection - Marche Region
Meteo Section
Snow Section
Via del Colle Ameno 5
60126 Torrette di Ancona, Ancona
Uff: 071 806 7743
E-mail: stefano.so...@regione.marche.it
---Oo---------oO----------------

________________________________________
Da: Eric Berger [ericjber...@gmail.com]
Inviato: martedì 22 settembre 2020 11.00
A: Jeff Newmiller
Cc: Stefano Sofia; r-help mailing list
Oggetto: Re: [R] aggregate semi-hourly data not 00-24 but 9-9

Thanks Jeff.
Stefano, per Jeff's comment, you can replace the line

df1$data_POSIXminus9 <- df1$data_POSIX - lubridate::hours(9)

by

df1$data_POSIXminus9 <- df1$data_POSIX - as.difftime(9,units="hours")

On Mon, Sep 21, 2020 at 8:06 PM Jeff Newmiller <jdnew...@dcn.davis.ca.us> wrote:
>
> The base R as.difftime function is perfectly usable to create this offset 
> without pulling in lubridate.
>
> On September 21, 2020 8:06:51 AM PDT, Eric Berger <ericjber...@gmail.com> 
> wrote:
> >Hi Stefano,
> >If you mean from 9am on one day to 9am on the following day, you can
> >do a trick. Simply subtract 9hrs from each timestamp and then you want
> >midnight to midnight for these adjusted times, which you can get using
> >the method you followed.
> >
> >I googled and found that lubridate::hours() can be used to add or
> >subtract hours from a POSIXct.
> >
> >library(lubridate)
> >
> >day_1 <- as.POSIXct("2020-02-19-00-00", format="%Y-%m-%d-%H-%M",
> >tz="Etc/GMT-1")
> >day_2 <- as.POSIXct("2020-02-24-12-00", format="%Y-%m-%d-%H-%M",
> >tz="Etc/GMT-1")
> >df1 <- data.frame(data_POSIX=seq(day_1, day_2, by="30 min"))
> >df1$hs <- rnorm(nrow(df1), 40, 10)
> >df1$diff[2:nrow(df1)] <- diff(df1$hs)
> >
> >df1$data_POSIXminus9 <- df1$data_POSIX - lubridate::hours(9)
> >df1$dayX <- format(df1$data_POSIXminus9,"%y-%m-%d")
> >df2X <- aggregate(diff ~ dayX, df1, sum)
> >df2X
> >
> >HTH,
> >Eric
> >
> >On Mon, Sep 21, 2020 at 5:30 PM Stefano Sofia
> ><stefano.so...@regione.marche.it> wrote:
> >>
> >> Dear R-list members,
> >> I have semi-hourly snowfall data.
> >> I should sum the semi-hourly increments (only the positive ones, but
> >this is not described in my example) day by day, not from 00 to 24 but
> >from 9 to 9.
> >>
> >> I am able to use the diff function, create a list of days and use the
> >function aggregate, but it works only from 0 to 24. Any suggestion for
> >an efficient way to do it?
> >> Here my code:
> >> day_1 <- as.POSIXct("2020-02-19-00-00", format="%Y-%m-%d-%H-%M",
> >tz="Etc/GMT-1")
> >> day_2 <- as.POSIXct("2020-02-24-12-00", format="%Y-%m-%d-%H-%M",
> >tz="Etc/GMT-1")
> >> df1 <- data.frame(data_POSIX=seq(day_1, day_2, by="30 min"))
> >> df1$hs <- rnorm(nrows(df1), 40, 10)
> >> df1$diff[2:nrow(df1)] <- diff(df1$hs)
> >> df1$day <- format(df$data_POSIX,"%y-%m-%d")
> >> df2 <- aggregate(diff ~ day, df, sum)
> >>
> >> Thank you for your help
> >> Stefano
> >>
> >>          (oo)
> >> --oOO--( )--OOo----------------
> >> Stefano Sofia PhD
> >> Civil Protection - Marche Region
> >> Meteo Section
> >> Snow Section
> >> Via del Colle Ameno 5
> >> 60126 Torrette di Ancona, Ancona
> >> Uff: 071 806 7743
> >> E-mail: stefano.so...@regione.marche.it
> >> ---Oo---------oO----------------
> >>
> >> ________________________________
> >>
> >> AVVISO IMPORTANTE: Questo messaggio di posta elettronica può
> >contenere informazioni confidenziali, pertanto è destinato solo a
> >persone autorizzate alla ricezione. I messaggi di posta elettronica per
> >i client di Regione Marche possono contenere informazioni confidenziali
> >e con privilegi legali. Se non si è il destinatario specificato, non
> >leggere, copiare, inoltrare o archiviare questo messaggio. Se si è
> >ricevuto questo messaggio per errore, inoltrarlo al mittente ed
> >eliminarlo completamente dal sistema del proprio computer. Ai sensi
> >dell’art. 6 della DGR n. 1394/2008 si segnala che, in caso di necessità
> >ed urgenza, la risposta al presente messaggio di posta elettronica può
> >essere visionata da persone estranee al destinatario.
> >> IMPORTANT NOTICE: This e-mail message is intended to be received only
> >by persons entitled to receive the confidential information it may
> >contain. E-mail messages to clients of Regione Marche may contain
> >information that is confidential and legally privileged. Please do not
> >read, copy, forward, or store this message unless you are an intended
> >recipient of it. If you have received this message in error, please
> >forward it to the sender and delete it completely from your computer
> >system.
> >>
> >> --
> >> Questo messaggio  stato analizzato da Libra ESVA ed  risultato non
> >infetto.
> >> This message was scanned by Libra ESVA and is believed to be clean.
> >>
> >>
> >>         [[alternative HTML version deleted]]
> >>
> >> ______________________________________________
> >> R-help@r-project.org mailing list -- To UNSUBSCRIBE and more, see
> >>  
> >> https://urlsand.esvalabs.com/?u=https%3A%2F%2Fstat.ethz.ch%2Fmailman%2Flistinfo%2Fr-help&e=52342f8a&h=d46bc785&f=y&p=y
> >> PLEASE do read the posting guide
> > https://urlsand.esvalabs.com/?u=http%3A%2F%2Fwww.R-project.org%2Fposting-guide.html&e=52342f8a&h=9b25bfd5&f=y&p=y
> >> and provide commented, minimal, self-contained, reproducible code.
> >
> >______________________________________________
> >R-help@r-project.org mailing list -- To UNSUBSCRIBE and more, see
> > https://urlsand.esvalabs.com/?u=https%3A%2F%2Fstat.ethz.ch%2Fmailman%2Flistinfo%2Fr-help&e=52342f8a&h=d46bc785&f=y&p=y
> >PLEASE do read the posting guide
> > https://urlsand.esvalabs.com/?u=http%3A%2F%2Fwww.R-project.org%2Fposting-guide.html&e=52342f8a&h=9b25bfd5&f=y&p=y
> >and provide commented, minimal, self-contained, reproducible code.
>
> --
> Sent from my phone. Please excuse my brevity.

--

Questo messaggio  stato analizzato con Libra ESVA ed  risultato non infetto.


________________________________

AVVISO IMPORTANTE: Questo messaggio di posta elettronica può contenere 
informazioni confidenziali, pertanto è destinato solo a persone autorizzate 
alla ricezione. I messaggi di posta elettronica per i client di Regione Marche 
possono contenere informazioni confidenziali e con privilegi legali. Se non si 
è il destinatario specificato, non leggere, copiare, inoltrare o archiviare 
questo messaggio. Se si è ricevuto questo messaggio per errore, inoltrarlo al 
mittente ed eliminarlo completamente dal sistema del proprio computer. Ai sensi 
dell’art. 6 della DGR n. 1394/2008 si segnala che, in caso di necessità ed 
urgenza, la risposta al presente messaggio di posta elettronica può essere 
visionata da persone estranee al destinatario.
IMPORTANT NOTICE: This e-mail message is intended to be received only by 
persons entitled to receive the confidential information it may contain. E-mail 
messages to clients of Regione Marche may contain information that is 
confidential and legally privileged. Please do not read, copy, forward, or 
store this message unless you are an intended recipient of it. If you have 
received this message in error, please forward it to the sender and delete it 
completely from your computer system.

--
Questo messaggio  stato analizzato da Libra ESVA ed  risultato non infetto.
This message was scanned by Libra ESVA and is believed to be clean.

______________________________________________
R-help@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.

Reply via email to