spell.length.max: Maximum spell length

In ECA-D/climind: ECAD Implementation of Climdex Routines

Maximum spell length

Description

This function returns the longest string of days which exceed or are below the given threshold.

Usage

spell.length.max(daily.prec, date.factor, threshold, op, spells.can.span.years)

Arguments

daily.prec	Data to compute index on.
date.factor	Date factor to split by.
threshold	The threshold to compare to.
op	The operator to use to compare data to threshold.
spells.can.span.years	Whether spells can span years.

Details

This routine compares data to the threshold using the given operator, generating a series of TRUE or FALSE values. It then computes the lengths of sequences of TRUE values (spells) and chooses the longest spell in each period (as defined by date.factor).

The spells.can.span.years option controls whether spells must always terminate at the end of a period, or whether they may continue until the criteria ceases to be met or the end of the data is reached. The default for fclimdex is TRUE.

Value

A timeseries of maximum spell lengths for each period.

See Also

climdex.cdd.

Examples

prec.dat <- c(0.1, 3.0, 4.3, 1.9, 1.3, 6.0, 0, 0, 4.0, 1)
phony.date.factor <- factor(rep(1:2, each=5))

## With spells spanning years...
cwd <- spell.length.max(prec.dat, phony.date.factor, 1, ">=", TRUE)

## Without spells spanning years...
altcwd <- spell.length.max(prec.dat, phony.date.factor, 1, ">=", FALSE)

ECA-D/climind documentation built on Nov. 26, 2022, 10:20 a.m.