doBy (version 4.6.22)

timeSinceEvent: Calculate "time since event" in a vector.

Description

Calculate "time since event" in a vector.

Usage

timeSinceEvent(yvar, tvar = seq_along(yvar))

Value

A dataframe with columns 'yvar', 'tvar', 'abs.tse' (absolute time since nearest event), 'sign.tse' (signed time since nearest event) and 'run' (indicator of the time window around each event).

Arguments

yvar

A numerical or logical vector specifying the events

tvar

An optional vector specifying time

Author

Søren Højsgaard,

Details

Events are coded as 1 in numeric vector (and non-events are coded with values different from 1). timeSinceEvent will give the time since event (with and without sign). In a logical vector, events are coded as TRUE and all non-events as FALSE.

See Also

subSeq, rle

Examples

## Events:
yvar <- c(0, 0, 0, 1, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 1, 0, 1, 0, 0, 0,
          0, 0, 0, 0, 0, 1, 1, 0, 0, 0, 0, 0)

## Plot results:
tse <- timeSinceEvent(yvar)
plot(sign.tse ~ tvar, data=tse, type="b")
grid()
rug(tse$tvar[tse$yvar==1], col=4, lwd=4)
points(scale(tse$run), col=tse$run, lwd=2)
lines(abs.tse + .2 ~ tvar, data=tse, type="b", col=3)

## Find times for which time since an event is at most 1:
tse$tvar[tse$abs <= 1]

yvar <- c(0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 1, 0, 0, 0, 0, 
0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0
)

tvar <- c(207, 208, 208, 208, 209, 209, 209, 209, 210, 210, 211, 211, 
211, 212, 213, 213, 214, 214, 215, 216, 216, 216, 216, 217, 217, 
217, 218, 218, 219, 219, 219, 219, 220, 220, 221, 221, 221, 221, 
222, 222, 222)

timeSinceEvent(yvar, tvar)