summary
Summarize an Object - Generic Function
Description
Provides a synopsis of an object.
This function is an S Version 3 generic (see Methods).
Method functions can be written to handle specific S Version 3 classes of
data. Classes that already have methods for this function include
aov, aovlist, data.frame, factor, glm,
lm, mlm, Date, POSIXct, POSIXlt.
Usage
summary(object, ...)
## S3 method for class 'Date':
summary(object, digits = 12L, ...)
## S3 method for class 'POSIXct':
summary(object, digits = 15L, ...)
## S3 method for class 'POSIXlt':
summary(object, digits = 15, ...)
Arguments
object |
any object, including a fitted model object of various kinds, a data
frame, or a factor.
|
digits |
a integer used by summary.default.
The results for numeric data will be rounded to 'digit' significant digits.
|
... |
some methods have additional arguments.
|
Details
Evaluates an object and returns a list of elements that describe the
contents of the object.
Value
returns a summary object. Usually, this object is a list-like object whose
elements describe the contents of the argument to summary().
For example, the method for lm objects produces an object of
class "summary.lm" that contains the components "residuals",
"correlation", "cov.unscaled", "r.squared", and more.
A print() method corresponds to each "summary." class,
so typing summary(object) does not save the summary;
rather, it produces a nicely-formatted table of a selection of
the components in the summary object.
More simple summary methods might not require a special class; for example,
the summary for factors is the value of a call to table().
See Also
Examples
summary(1:1000) # prints the quartiles, median and mean values.
## Date/Time
summary(Sys.Date() + 1:5)
summary(Sys.time() + 1:5)
summary(as.POSIXlt(Sys.time() + 1:5))