All: I have a SQlite database where I have stored some verification data by date & time (cycle Z/UTC), lead_time as well as type, duration, etc. I would like to analyze & plot the data as monthly averages. I have looked at a bunch of examples which use some combination of zoo and aggregate, but I have not been able to successfully apply bits and pieces from the examples I have found. Any help is appreciated. BTW, I calculate mae (mean absolute error), mse (mean squared error), me (mean error), and other measures obtained by using the R verification package.
The example below is limited to 20 records and shows lead_time, r_squared, (forecast) cycle, fcst_date (forecast date) -- the full data set is just over 2 years of daily data with 3 forecast cycles (00Z, 12Z, and 18Z) daily. >From my query, below) how do I construct an appropriate data structure to analyze & plot the data as monthly averages? Regards, Tom > q<-dbGetQuery(con,"select lead_time,r_squared,cycle,fcst_date from verify_table where duration=6 limit 20") > q lead_time r_squared cycle fcst_date 1 6 5.405095e-02 00 07/31/2010 2 12 5.521620e-06 00 07/31/2010 3 18 1.565910e-04 00 07/31/2010 4 24 8.646822e-02 00 07/31/2010 5 30 1.719604e-02 00 07/31/2010 6 36 5.768113e-04 00 07/31/2010 7 42 2.501269e-06 00 07/31/2010 8 48 6.451727e-02 00 07/31/2010 9 6 2.857931e-01 12 07/31/2010 10 12 1.138635e-01 12 07/31/2010 11 18 2.225503e-02 12 07/31/2010 12 24 1.182031e-03 12 07/31/2010 13 30 8.841142e-04 12 07/31/2010 14 36 1.082490e-01 12 07/31/2010 15 42 1.502887e-05 12 07/31/2010 16 48 NA 12 07/31/2010 17 6 8.689588e-02 00 08/01/2010 18 12 5.884336e-04 00 08/01/2010 19 18 2.219316e-07 00 08/01/2010 20 24 3.960752e-02 00 08/01/2010 -- Thomas E Adams National Weather Service Ohio River Forecast Center 1901 South State Route 134 Wilmington, OH 45177 EMAIL: thomas.ad...@noaa.gov VOICE: 937-383-0528 FAX: 937-383-0033 [[alternative HTML version deleted]] ______________________________________________ R-help@r-project.org mailing list 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.