The integral of the survival function from t1 to t2
Arguments
t1
Lower bound of the analysis time interval.
t2
Upper bound of the analysis time interval.
piecewiseSurvivalTime
A vector that specifies the starting time of
piecewise exponential survival time intervals. Must start with 0, e.g.,
c(0, 6) breaks the time axis into 2 event intervals:
[0, 6) and [6, Inf).
Defaults to 0 for exponential distribution.
lambda
A vector of hazard rates for the event. One for
each analysis time interval.