Stefano Sofia
2016-Jun-07 06:55 UTC
[R] evaluate the daily mean with date in "POSIXct" "POSIXt" class
Dear R-list users, I have the following data frame, called MteBove: posix_date snow temp ... 2010-01-20 23:30:00 45 NA 2010-01-02 00:30:00 10-2.7 2010-01-20 03:00:00 45 NA 2010-01-20 03:30:00 44 NA 2010-01-20 04:00:00 44 NA 2010-01-20 04:30:00 44 NA 2010-01-20 05:00:00 44 NA 2010-01-20 05:30:00 45 NA 2010-01-20 06:00:00 44 NA 2010-01-20 06:30:00 45 NA ...> sapply(MteBove, class)gives $posix_date [1] "POSIXct" "POSIXt" $snow [1] "numeric" $temp [1] "numeric" There are semi-hourly data (i.e. 48 data each day) from the first of November to the first of May of each Winter season, and I need the daily mean for snow and temp. First I created a subset for each Winter season I tried to create a new column with only the day, like> MteBove$day <- trunc(MteBove$posix_date, "days")and then> list_days <- unique(MteBove$day) > means <- rapply(list_days, function(x) mean(MteBove[MteBove$day == x, ], na.rm=T))with the following result: [1] "means IS" sec min hour mday mon year wday yday isdst NA NA NA NA NA NA NA NA NA I tried some changes always in this direction, with no success. Is there an efficient way to do that? Could somebody give me an hint about it? Thank you for your attention and your help Stefano Sofia ________________________________ AVVISO IMPORTANTE: Questo messaggio di posta elettronica pu? contenere informazioni confidenziali, pertanto ? 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 ? il destinatario specificato, non leggere, copiare, inoltrare o archiviare questo messaggio. Se si ? 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 necessit? ed urgenza, la risposta al presente messaggio di posta elettronica pu? 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. [[alternative HTML version deleted]]
Jim Lemon
2016-Jun-07 07:39 UTC
[R] evaluate the daily mean with date in "POSIXct" "POSIXt" class
Hi Stefano, I might be missing something, but try this: MteBove<-read.table(text="posix_date posix_time snow temp 2010-01-19 23:30:00 45 NA 2010-01-20 00:30:00 10 2.7 2010-01-20 03:00:00 45 NA 2010-01-20 03:30:00 44 NA 2010-01-20 04:00:00 44 NA 2010-01-20 04:30:00 44 NA 2010-01-20 05:00:00 44 NA 2010-01-20 05:30:00 45 NA 2010-01-20 06:00:00 44 NA 2010-01-20 06:30:00 45 NA 2010-01-20 23:30:00 45 NA 2010-01-21 00:30:00 10 2.7 2010-01-21 03:00:00 45 NA 2010-01-21 03:30:00 44 NA 2010-01-21 04:00:00 44 NA 2010-01-21 04:30:00 44 NA 2010-01-21 05:00:00 44 NA 2010-01-21 05:30:00 45 NA 2010-01-21 06:00:00 44 NA 2010-01-21 06:30:00 45 NA", header=TRUE) MteBove$day<-as.Date(MteBove$posix_date,"%Y-%m-%d") by(MteBove$snow,MteBove$day,mean) and if you have NA values, add na.rm=TRUE to the last line. Jim On Tue, Jun 7, 2016 at 4:55 PM, Stefano Sofia <stefano.sofia at regione.marche.it> wrote:> Dear R-list users, > I have the following data frame, called MteBove: > > posix_date snow temp > ... > 2010-01-20 23:30:00 45 NA > 2010-01-02 00:30:00 10-2.7 > 2010-01-20 03:00:00 45 NA > 2010-01-20 03:30:00 44 NA > 2010-01-20 04:00:00 44 NA > 2010-01-20 04:30:00 44 NA > 2010-01-20 05:00:00 44 NA > 2010-01-20 05:30:00 45 NA > 2010-01-20 06:00:00 44 NA > 2010-01-20 06:30:00 45 NA > ... > >> sapply(MteBove, class) > gives > $posix_date > [1] "POSIXct" "POSIXt" > > $snow > [1] "numeric" > > $temp > [1] "numeric" > > There are semi-hourly data (i.e. 48 data each day) from the first of November to the first of May of each Winter season, and I need the daily mean for snow and temp. > First I created a subset for each Winter season > I tried to create a new column with only the day, like > >> MteBove$day <- trunc(MteBove$posix_date, "days") > > and then > >> list_days <- unique(MteBove$day) >> means <- rapply(list_days, function(x) mean(MteBove[MteBove$day == x, ], na.rm=T)) > > with the following result: > [1] "means IS" > sec min hour mday mon year wday yday isdst > NA NA NA NA NA NA NA NA NA > > I tried some changes always in this direction, with no success. > Is there an efficient way to do that? > Could somebody give me an hint about it? > > Thank you for your attention and your help > Stefano Sofia > > > ________________________________ > > AVVISO IMPORTANTE: Questo messaggio di posta elettronica pu? contenere informazioni confidenziali, pertanto ? 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 ? il destinatario specificato, non leggere, copiare, inoltrare o archiviare questo messaggio. Se si ? 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 necessit? ed urgenza, la risposta al presente messaggio di posta elettronica pu? 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. > > [[alternative HTML version deleted]] > > ______________________________________________ > 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.
Stefano Sofia
2016-Jun-07 14:34 UTC
[R] evaluate the daily mean with date in "POSIXct" "POSIXt" class
Thank you Jim, you gave me the right hint. Stefano ________________________________________ Da: Jim Lemon [drjimlemon at gmail.com] Inviato: marted? 7 giugno 2016 9.39 A: Stefano Sofia Cc: r-help at r-project.org Oggetto: Re: [R] evaluate the daily mean with date in "POSIXct" "POSIXt" class Hi Stefano, I might be missing something, but try this: MteBove<-read.table(text="posix_date posix_time snow temp 2010-01-19 23:30:00 45 NA 2010-01-20 00:30:00 10 2.7 2010-01-20 03:00:00 45 NA 2010-01-20 03:30:00 44 NA 2010-01-20 04:00:00 44 NA 2010-01-20 04:30:00 44 NA 2010-01-20 05:00:00 44 NA 2010-01-20 05:30:00 45 NA 2010-01-20 06:00:00 44 NA 2010-01-20 06:30:00 45 NA 2010-01-20 23:30:00 45 NA 2010-01-21 00:30:00 10 2.7 2010-01-21 03:00:00 45 NA 2010-01-21 03:30:00 44 NA 2010-01-21 04:00:00 44 NA 2010-01-21 04:30:00 44 NA 2010-01-21 05:00:00 44 NA 2010-01-21 05:30:00 45 NA 2010-01-21 06:00:00 44 NA 2010-01-21 06:30:00 45 NA", header=TRUE) MteBove$day<-as.Date(MteBove$posix_date,"%Y-%m-%d") by(MteBove$snow,MteBove$day,mean) and if you have NA values, add na.rm=TRUE to the last line. Jim On Tue, Jun 7, 2016 at 4:55 PM, Stefano Sofia <stefano.sofia at regione.marche.it> wrote:> Dear R-list users, > I have the following data frame, called MteBove: > > posix_date snow temp > ... > 2010-01-20 23:30:00 45 NA > 2010-01-02 00:30:00 10-2.7 > 2010-01-20 03:00:00 45 NA > 2010-01-20 03:30:00 44 NA > 2010-01-20 04:00:00 44 NA > 2010-01-20 04:30:00 44 NA > 2010-01-20 05:00:00 44 NA > 2010-01-20 05:30:00 45 NA > 2010-01-20 06:00:00 44 NA > 2010-01-20 06:30:00 45 NA > ... > >> sapply(MteBove, class) > gives > $posix_date > [1] "POSIXct" "POSIXt" > > $snow > [1] "numeric" > > $temp > [1] "numeric" > > There are semi-hourly data (i.e. 48 data each day) from the first of November to the first of May of each Winter season, and I need the daily mean for snow and temp. > First I created a subset for each Winter season > I tried to create a new column with only the day, like > >> MteBove$day <- trunc(MteBove$posix_date, "days") > > and then > >> list_days <- unique(MteBove$day) >> means <- rapply(list_days, function(x) mean(MteBove[MteBove$day == x, ], na.rm=T)) > > with the following result: > [1] "means IS" > sec min hour mday mon year wday yday isdst > NA NA NA NA NA NA NA NA NA > > I tried some changes always in this direction, with no success. > Is there an efficient way to do that? > Could somebody give me an hint about it? > > Thank you for your attention and your help > Stefano Sofia > > > ________________________________ > > AVVISO IMPORTANTE: Questo messaggio di posta elettronica pu? contenere informazioni confidenziali, pertanto ? 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 ? il destinatario specificato, non leggere, copiare, inoltrare o archiviare questo messaggio. Se si ? 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 necessit? ed urgenza, la risposta al presente messaggio di posta elettronica pu? 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. > > [[alternative HTML version deleted]] > > ______________________________________________ > 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.________________________________ AVVISO IMPORTANTE: Questo messaggio di posta elettronica pu? contenere informazioni confidenziali, pertanto ? 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 ? il destinatario specificato, non leggere, copiare, inoltrare o archiviare questo messaggio. Se si ? 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 necessit? ed urgenza, la risposta al presente messaggio di posta elettronica pu? 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.