vector of times; the returned matrix will contain 1 row for each time.
This must be in increasing order and missing values are not allowed.
If censored=T, the default times vector contains all the unique times in
fit,
otherwise the default times vector uses only the event (death) times.
censored:
logical value: if TRUE, the censoring times are included in the output.
This is ignored if the times argument is present.
scale:
numeric value to rescale the survival time,
e.g., if the input data to survfit were in days,
scale = 365.25 would scale the output to years.
VALUE:
a list with the following components:
surv:
the estimate of survival at time t+0.
time:
the timepoints at which the curve has a step.
n.risk:
the number of subjects at risk at time t-0
(but see the comments on weights in the survfit help file).
n.event:
if the times argument is missing, this column is the number of
events that occurred at time t.
Otherwise, it is the cumulative number of events that have occurred
since the last time listed until time t+0.
std.err:
the standard error of the survival value.
conf.int:
level of confidence for the confidence intervals of survival.
lower:
lower confidence limits for the curve.
upper:
upper confidence limits for the curve.
strata:
indicates stratification of curve estimation. If strata is not NULL,
there are multiple curves in the result and the surv, time, n.risk, etc.
vectors will contain multiple curves, pasted end to end.
The levels of strata (a factor) are the labels for the curves.