Surv-methods {survival} | R Documentation |
Methods for Surv objects
Description
The list of methods that apply to Surv
objects
Usage
## S3 method for class 'Surv'
anyDuplicated(x, ...)
## S3 method for class 'Surv'
as.character(x, ...)
## S3 method for class 'Surv'
as.data.frame(x, ...)
## S3 method for class 'Surv'
as.integer(x, ...)
## S3 method for class 'Surv'
as.matrix(x, ...)
## S3 method for class 'Surv'
as.numeric(x, ...)
## S3 method for class 'Surv'
c(...)
## S3 method for class 'Surv'
duplicated(x, ...)
## S3 method for class 'Surv'
format(x, ...)
## S3 method for class 'Surv'
head(x, ...)
## S3 method for class 'Surv'
is.na(x)
## S3 method for class 'Surv'
length(x)
## S3 method for class 'Surv'
mean(x, ...)
## S3 method for class 'Surv'
median(x, na.rm=FALSE, ...)
## S3 method for class 'Surv'
names(x)
## S3 replacement method for class 'Surv'
names(x) <- value
## S3 method for class 'Surv'
quantile(x, probs, na.rm=FALSE, ...)
## S3 method for class 'Surv'
plot(x, ...)
## S3 method for class 'Surv'
rep(x, ...)
## S3 method for class 'Surv'
rep.int(x, ...)
## S3 method for class 'Surv'
rep_len(x, ...)
## S3 method for class 'Surv'
rev(x)
## S3 method for class 'Surv'
t(x)
## S3 method for class 'Surv'
tail(x, ...)
## S3 method for class 'Surv'
unique(x, ...)
Arguments
x |
a |
probs |
a vector of probabilities |
na.rm |
remove missing values from the calculation |
value |
a character vector of up to the same length as |
... |
other arguments to the method |
Details
These functions extend the standard methods to Surv
objects.
The arguments and results from these are mostly as expected, with the
following further details:
The
as.character
function uses "5+" for right censored at time 5, "5-" for left censored at time 5, "[2,7]" for an observation that was interval censored between 2 and 7, "(1,6]" for a counting process data denoting an observation which was at risk from time 1 to 6, with an event at time 6, and "(1,6+]" for an observation over the same interval but not ending with and event. For a multi-state survival object the type of event is appended to the event time using ":type".The
print
andformat
methods make use ofas.character
.The
as.numeric
andas.integer
methods perform these actions on the survival times, but do not affect the censoring indicator.The
as.matrix
andt
methods return a matrixThe
length
of aSurv
object is the number of survival times it contains, not the number of items required to encode it, e.g.,x <- Surv(1:4, 5:9, c(1,0,1,0)); length(x)
has a value of 4. Likewisenames(x)
will be NULL or a vector of length 4. (For technical reasons, any names are actually stored in therownames
attribute of the object.)For a multi-state survival object
levels
returns the names of the endpoints, otherwise it is NULL.The
median
,quantile
andplot
methods first construct a survival curve usingsurvfit
, then apply the appropriate method to that curve.The concatonation method
c()
is asymmetric, its first argument determines the exection path. For instancec(Surv(1:4), Surv(5:6))
will concatonate the two objects,c(Surv(1:4), 5:6)
will give an error, andc(5:6, Surv(1:4))
is equivalent toc(5:6, as.vector(Surv(1:4)))
.