| head {utils} | R Documentation |
Return the First or Last Part of an Object
Description
Returns the first or last parts of a vector, matrix, data frame or function.
Usage
head(x, ...)
## Default S3 method:
head(x, n = 6, ...)
## S3 method for class 'data.frame'
head(x, n = 6, ...)
## S3 method for class 'matrix'
head(x, n = 6, ...)
tail(x, ...)
## Default S3 method:
tail(x, n = 6, ...)
## S3 method for class 'data.frame'
tail(x, n = 6, ...)
## S3 method for class 'matrix'
tail(x, n = 6, addrownums = TRUE, ...)
Arguments
x |
an object |
n |
size for the resulting object: number of elements for a vector (including lists), rows for a matrix or data frame or lines for a function. |
addrownums |
if there are no row names, create them from the row numbers. |
... |
arguments to be passed to or from other methods. |
Details
For matrices and data frames, the first/last n rows are returned.
For functions, the first/last n lines of the deparsed function are
returned as character strings.
If a matrix has no row names, then tail() will add row names of
the form "[n,]" to the result, so that it looks similar to the last lines of x
when printed. Setting addrownums = FALSE suppresses this behaviour.
Value
An object (usually) like x but generally smaller.
Author(s)
Patrick Burns, improved and corrected by R-Core
Examples
head(freeny.x, n = 10)
head(freeny.y)
tail(freeny.x)
tail(freeny.y)
tail(library)