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.
