climdex.pcic (version 0.6-2)

spell.length.max: 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.

Value

• A timeseries of maximum spell lengths for each period.

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.

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)