RMAWGEN (version 1.3.7)

continuity_ratio: Calculates the continuity ratio of a set of precipitation measured or generated data in several sites as defined by Wilks, 1998 (see reference link)

Description

Calculates the continuity ratio of a set of precipitation measured or generated data in several sites as defined by Wilks, 1998 (see reference link)

Usage

continuity_ratio(data, lag = 0, valmin = 0.5)

Arguments

data

containing daily precipitation time series for several gauges (one gauge time series per column)

lag

numeric lag (expressed as number of days) used for computation for "cross" continuity ratio and joint probability of prercipitation (no)occurrence.

valmin

threshold precipitation value [mm] for wet/dry day indicator. If precipitation is lower than valmin, day is considered dry. Default is 0.5 mm.

Value

A list containing the following matrices:

continuity_ratio : lag-day lagged continuity ratio ,

occurrence : joint probability of lag-day lagged precipitation occurrence

nooccurrence : joint probability of lag-day lagged no precipitation occurrence.

nooccurrence_occurrence : joint probability of lag-day lagged no precipitation and precipitation occurrence respectively.

occurrence_nooccurrence : joint probability of lag-day lagged precipitation and no precipitation occurrence respectively.

probability_continuity_ratio: lag-day lagged ratio about precipitation probability contitioned to no precipitation/preciitation occurrence in the other site

References

see the following URL references: http://onlinelibrary.wiley.com/doi/10.1002/joc.2305/abstract and http://www.sciencedirect.com/science/article/pii/S0022169498001863

Examples

# NOT RUN {
data(trentino)

year_min <- 1961
year_max <- 1990
origin <- paste(year_min,1,1,sep="-")

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[,1:2]

continuity_ratio <-continuity_ratio(data=prec_mes,lag=0,valmin=0.5)
continuity_ratio1 <-continuity_ratio(data=prec_mes,lag=-1,valmin=0.5)


# }