library(dplyr) library(lubridate) data %>% group_by(floor_date(Timestamp, unit = "day")) %>% summarise(rain = sum(Rain_mm_tot))
ir. Thierry Onkelinx Instituut voor natuur- en bosonderzoek / Research Institute for Nature and Forest team Biometrie & Kwaliteitszorg / team Biometrics & Quality Assurance Kliniekstraat 25 1070 Anderlecht Belgium To call in the statistician after the experiment is done may be no more than asking him to perform a post-mortem examination: he may be able to say what the experiment died of. ~ Sir Ronald Aylmer Fisher The plural of anecdote is not data. ~ Roger Brinner The combination of some data and an aching desire for an answer does not ensure that a reasonable answer can be extracted from a given body of data. ~ John Tukey 2017-08-03 12:31 GMT+02:00 T Wan <t...@web.de>: > Hi there, > > I am trying to get the sum of rain per day. > > That is what the data-set looks like: > > > Timestamp Rain_mm_Tot > 2017-05-29 23:40:00 4.7999980 > 2017-05-29 23:50:00 1.2000000 > 2017-05-30 00:10:00 2.5800000 > 2017-05-30 00:20:00 1.2009600 > 2017-05-30 00:30:00 1.2000006 > 2017-05-30 00:40:00 2.5002480 > > First I tried to define the column as date format with: > data_date <-data[as.Date(data_date$Timestamp)<=as.Date("2017-06-15"),] > > > Then I tried to aggregate as followed: > data_date_sum <- aggregate(data_date$Timestamp, on = "days", k=1, > by=list(cut(as.Date(data_date$Date))), FUN=sum) > > > R responds: > Error in as.Date.default(data_date$Date) : > do not know how to convert 'data_date$Date' to class “Date” > > > I read serveral post, but no other fits to my format. > Because I am a beginner I am open for completely new ideas to sum the > daily rain also. > > Thanks a lot and all the best > Torben > > > [[alternative HTML version deleted]] > > ______________________________________________ > 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. [[alternative HTML version deleted]] ______________________________________________ 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.