Dear R-users, from a data frame of half-hourly wind observations (direction and speed, three years data), I need to evaluate the first main direction for each period of three hours (h03, h06, h09, h12, h15, h18, h21, h24 of each day).
The command "windRose" of the package "openair" crates a data frame that contains the information I need. Can I ask you which is the most efficient way to run the windRose command for each subset of three hours? The initial data frame is called wind_df is like Date Direction Speed 2015-06-30 00:30:00 315 2.9 2015-06-30 01:00:00 338 3.5 2015-06-30 01:30:00 23 4.8 2015-06-30 02:00:00 338 4.1 2015-06-30 02:30:00 135 1.1 2015-06-30 03:00:00 45 2.7 2015-06-30 03:30:00 1.7 2015-06-30 04:00:00 293 1 2015-06-30 04:30:00 45 1.5 2015-06-30 05:00:00 45 2.3 ... The command for the wind rose creation is output1_df <- windRose(wind_df, ws="Speed", wd="Direction", layout=c(1,1), ws.int=4, angle=22.5, type="default", bias.corr=TRUE, cols="default", grid.line=NULL, width=2, seg=NULL, auto.text=TRUE, breaks=c(0,0.3,1.5,3.4,5.4,7.9,10.7,13.8,17.1,20.7,24.4,28.4,32.6,40), offset=5, normalise=TRUE, max.freq=NULL, paddle=TRUE, key.header=NULL, key.footer="(km/hr)", key.position="bottom", key=TRUE, dig.lab=2, statistic="prop.count", pollutant=NULL, annotate=TRUE, border=NA, par.settings=list(fontsize=list(text=10))) and I evaluate the first main direction through output2_df <- output1_df$data output2_df$wd[output2_df$freqs == max(output2_df$freqs)]) Thank you for your attention and your help Stefano Sofia ________________________________ 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. [[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.