interarrival {seas} | R Documentation |
Calculate the interarrivals (or spell periods), which are the number of days between precipitation events (dry days), and the number of days of continuous precipitation (wet days).
# minimum interarrival(dat) # with optional arguments interarrival(dat, start, end, var = "precip", p.cut = 0.3, inv = FALSE, id)
dat |
data.frame , must have at least date and a
field to calculate an interarrival with (such as precip) |
start |
start year; if omitted minimum year will be used |
end |
end year; if omitted will use same as start , and if
start is omitted, will use maximum year |
var |
variable on to which the interarrivals are calculated;
default is precip |
p.cut |
days with precipitation values greater than p.cut
are considered to be wet days, and the complement are
dry days; a trace amount of 0.3 mm is suggested |
inv |
logical ; invert convention of the starting date such
that the date is the first wet day if inv=FALSE
(default), or the date is the first dry day if
inv=TRUE |
id |
unique station identifier used to extract a subset of data
from dat |
The interarrival is the same as the spell period (i.e., dry
spell), however this function simultaneously counts the number of
dry and wet days relative to a single date. The date
represents the first day of precipitation (if inv=TRUE
, this
convention is inverted to the first day of non-precipitation).
Missing or NA
precipitation values voids the number of counted
days between and within segments, which implies that days without
precipitation need to explicitly have zeros.
interarrival
object (which inherits the data.frame
class) with date
, wet
, dry
and fact
fields
(if supplied with a width
value).
M.W. Toews
von Storch, H. and Zwiers, F.W., 1999, Statistical analysis in climate research, Cambridge: Cambridge University Press, 484 p.
data(mscdata) van.int <- interarrival(mscdata, id=1108447) plot(van.int, log=FALSE, maxy=30)