It calculates the number of wet days for each month and each year
nwetdays(data, valmin = 0.5, origin = "1961-1-1", station = names(data))data frame R object containing daily precipitation time series for several gauges (one gauge time series per column).
threshold precipitation value [mm] for wet/dry day indicator.
character string "yyyy-mm-dd" indicated the date of the first row of "data".
character string indicating the stations. Default is names(data)
Function returns a list of data frames containing the spell length expressed in days
data(trentino)
year_min <- 1961
year_max <- 1990
period <- PRECIPITATION$year>=year_min & PRECIPITATION$year<=year_max
station <- names(PRECIPITATION)[!(names(PRECIPITATION) %in% c("day","month","year"))]
prec_mes <- PRECIPITATION[period,station]
## removing nonworking stations (e.g. time series with NA)
accepted <- array(TRUE,length(names(prec_mes)))
names(accepted) <- names(prec_mes)
for (it in names(prec_mes)) {
accepted[it] <- (length(which(!is.na(prec_mes[,it])))==length(prec_mes[,it]))
}
prec_mes <- prec_mes[,accepted]
## the dateset is reduced!!!
prec_mes <- prec_mes[,1:3]
origin <- paste(year_min,1,1,sep="-")
nwetdays <- nwetdays(prec_mes,origin)
#> chr [1:3] "T0001" "T0014" "T0021"
#> 'data.frame': 360 obs. of 5 variables:
#> $ month: num 0 0 0 0 0 0 0 0 0 0 ...
#> $ year : num 0 0 0 0 0 0 0 0 0 0 ...
#> $ T0001: num 0 0 0 0 0 0 0 0 0 0 ...
#> $ T0014: num 0 0 0 0 0 0 0 0 0 0 ...
#> $ T0021: num 0 0 0 0 0 0 0 0 0 0 ...