Vectorclassleftovers: Vector objects (old man page)
Description
IMPORTANT NOTE  4/29/2014: This man page is being refactored. Most of
the things that used to be documented here have been moved to the man
page for Vector objects located in the S4Vectors
package.
Evaluation
In the following code snippets, x
is a Vector object.

with(x, expr)
: Evaluates expr
within
as.env(x)
via eval(x)
.

eval(expr, envir, enclos=parent.frame())
: Evaluates
expr
within envir
, where envir
is coerced to
an environment with as.env(envir, enclos)
. The expr
is first processed with bquote
, such that any
escaped symbols are directly resolved in the calling frame.
Convenience wrappers for common subsetting operations
In the code snippets below, x
is a Vector object or regular R vector
object. The R vector object methods for window
are defined in this
package and the remaining methods are defined in base R.

window(x, start=NA, end=NA, width=NA)
:
Extract the subsequence window from the Vector object using:
start
, end
, width
 The start, end, or width
of the window. Two of the three are required.

window(x, start=NA, end=NA, width=NA) < value
:
Replace the subsequence window specified on the left (i.e. the
subsequence in x
specified by start
, end
and
width
) by value
.
value
must either be of class class(x)
, belong to a
subclass of class(x)
, or be coercible to class(x)
or a
subclass of class(x)
.
The elements of value
are repeated to create a Vector with the
same number of elements as the width of the subsequence window it is
replacing.

head(x, n = 6L)
:
If n
is nonnegative, returns the first n elements of the Vector
object.
If n
is negative, returns all but the last abs(n)
elements
of the Vector object.

tail(x, n = 6L)
:
If n
is nonnegative, returns the last n elements of the Vector
object.
If n
is negative, returns all but the first abs(n)
elements
of the Vector object.

rev(x)
:
Return a new Vector object made of the original elements in the reverse
order.

rep(x, times, length.out, each)
, rep.int(x, times)
:
Repeats the values in x
through one of the following conventions:
times
 Vector giving the number of times to repeat each
element if of length
length(x)
, or to repeat the whole vector
if of length 1. length.out
 Nonnegative integer. The desired length of
the output vector.
each
 Nonnegative integer. Each element of
x
is
repeated each
times.

subset(x, subset)
:
Return a new Vector object made of the subset using logical vector
subset
, where missing values are taken as FALSE.
Combining
In the code snippets below, x
is a Vector object.
mstack(..., .index.var = "name")
: A variant of
stack
, where the list is taken as the list of
arguments in ...
, each of which should be a Vector
or vector
(mixing the two will not work).
Looping
In the code snippets below, x
is a Vector object.

tapply(X, INDEX, FUN = NULL, ..., simplify = TRUE)
:
Like the standard tapply
function defined in the
base package, the tapply
method for Vector objects applies a
function to each cell of a ragged array, that is to each (nonempty)
group of values given by a unique combination of the levels of certain
factors.
Coercion

as.list(x)
: coerce a Vector to a list, where the i
th
element of the result corresponds to x[i]
.
See Also
The Vector class defined and documented in the
S4Vectors package.