breaks.AP: Estimate the Number of Sit to Stand Transitions
In activpalProcessing: Process activPAL Events Files

Description Usage Arguments Value Author(s) Examples

This function estimates the number of sit to stand transitions. This function works on a numeric vector where 0 indicates sitting, 1 indicates standing and 2 indicates stepping. The sum of the instances AP posture transitions from 0 to 1 or 0 to 2.

1	breaks.AP(posture)

posture

a numeric vector (in any epoch) where 0 indicates sitting, 1 indicates standing and 2 indicates stepping.

Numeric value indicating breaks from sitting

John Staudenmayer

data(second.by.second)
posture <- second.by.second.data$ap.posture	

breaks.AP(posture)

# summarize by date
tapply(second.by.second.data$ap.posture, second.by.second.data$date, breaks.AP)