dw.spell | R Documentation |
It calculates dry/wet spell duration.
dw.spell( data, valmin = 0.5, origin = "1961-1-1", extract = NULL, month = 1:12, melting.df = FALSE, from.start = FALSE, only.inner = FALSE )
data |
data frame R object containing daily precipitation time series for several gauges (one gauge time series per column). |
valmin |
threshold precipitation value [mm] for wet/dry day indicator. |
origin |
character string |
extract |
string character referred to the state to be extracted, eg. |
month |
integer vectors containing the considered months. Default is |
melting.df |
logical value. If it |
from.start |
logical value. If is |
only.inner |
logical value. It is used in case |
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="-") dw_spell <- dw.spell(prec_mes,origin=origin) dw_spell_dry <- dw.spell(prec_mes,origin=origin,extract="dry") hist(dw_spell_dry$T0001$spell_length) ## Single Gauging Station prec_mes <- prec_mes[,1] origin <- paste(year_min,1,1,sep="-") dw_spell <- dw.spell(prec_mes,origin=origin) dw_spell_dry <- dw.spell(prec_mes,origin=origin,extract="dry") dw_spell_dry_start <- dw.spell(prec_mes,origin=origin,extract="dry", month=5:8,from.start=TRUE) ## dry spell dw_spell_dry_start_2 <- dw.spell(prec_mes,origin=origin,extract="dry", month=5:8,from.start=TRUE,only.inner=TRUE) ## dry spell ## is referenced to the first day instead of the latest one as default. hist(dw_spell_dry[[1]]$spell_length)
Add the following code to your website.
For more information on customizing the embed code, read Embedding Snippets.