Dear Bruce, I think this should be straightforward with tidyverse. If not please provide a small reproducible data set with dput().
library(tidyverse) count(Active, Time) count(Active, Date, Time) Best regards, ir. Thierry Onkelinx Statisticus / Statistician Vlaamse Overheid / Government of Flanders INSTITUUT VOOR NATUUR- EN BOSONDERZOEK / RESEARCH INSTITUTE FOR NATURE AND FOREST Team Biometrie & Kwaliteitszorg / Team Biometrics & Quality Assurance thierry.onkel...@inbo.be Havenlaan 88 bus 73, 1000 Brussel www.inbo.be /////////////////////////////////////////////////////////////////////////////////////////// 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 /////////////////////////////////////////////////////////////////////////////////////////// <https://www.inbo.be> Op ma 30 nov. 2020 om 16:48 schreef Neotropical bat risk assessments and acoustic tools <neotropical.b...@gmail.com>: > Hi all, > > I need to summarize temporal activity. However date\times in R seem to > be not easily handled. > Seems I may need to convert date\time values to a recognizable format? > > My "raw data" is tab (text) includes a location ID, date and time(24 hr > format). > Format is like this: > Location Date Time > 156 2/25/2008 18:31 > 156 2/25/2008 18:31 > 156 2/25/2008 18:32 > 156 2/25/2008 18:35 > 156 2/25/2008 18:38 > 156 2/25/2008 18:41 > 156 2/25/2008 18:42 > 156 2/25/2008 18:43 > 156 2/25/2008 18:43 > 156 2/25/2008 18:55 > 156 2/25/2008 18:56 > 156 2/25/2008 18:56 > 156 2/26/2008 18:35 > 156 2/26/2008 18:35 > 156 2/26/2008 18:35 > 156 2/26/2008 18:35 > 196 7/16/2006 4:47 > 250 4/9/2004 18:41 > 250 4/9/2004 18:44 > 253 3/5/2004 18:30 > 1268 2/11/2001 18:39 > 1268 2/11/2001 18:39 > 1344 4/17/2003 19:06 > 1409 2/28/2004 5:51 > ...etc. for 10,390 rows of data. > > I am aiming for a summary by times for all of the data such that I have > total number of "events" or count for each time period. So something like > > 18:31 41 > 18:32 38 > > and so on. > > So a "simple" count of the time occurrences. > > I tried to do a summary running frequencies > descriptive.table(vars = d(Time) , > + strata = d(Date),data= Active, > + func.names =c("Valid N","Minimum","Maximum")) > > > Warning message: > In descriptive.table(vars = d(Time), strata = d(Date), data = Active, : > Non-numeric variables dropped from descriptive table > > Active[,3]<-as.POSIXct(Active[,3], format='%m-%d-%y %H:%M:%S') > > Active[,2]<-as.Date(Active[,2], format= '%m/%d/%y') > > frequencies(Active[c("Time")] , r.digits = 1) > Error in names(x) <- value : > 'names' attribute [4] must be the same length as the vector [3] > > Suggestions welcomed. > > Cheers all > > -- > Bruce W. Miller, PhD. > Neotropical bat risk and acoustic assessments > Conservation Fellow - Wildlife Conservation Society > Research Associate, American Museum of Natural History > > If we lose the bats, we may lose much of the tropical vegetation and the > lungs of the planet > > Using acoustic sampling to identify and map species distributions > and pioneering acoustic tools for ecology and conservation of bats for >25 > years. > > Key projects include providing free interactive identification keys and > call fact sheets for the vocal signatures of New World Bats > > ______________________________________________ > 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.