DataTable-class {IRanges} | R Documentation |
The DataTable virtual class provides an interface for the storing rectangular
data sets, like a basic data.frame object. It extends Sequence
.
In the following code snippets, x
is a DataTable
.
dim(x)
:
Get the length two integer vector indicating in the first and second
element the number of rows and columns, respectively. This implies the
existence of nrow(x)
and ncol(x)
.
dimnames(x)
:
Get the length two list of character vectors indicating in the first
and second element the names of the rows and columns, respectively.
This implies the existence of rownames(x)
and colnames(x)
.
In the code snippets below, x
is a DataTable object.
cbind(...)
: Creates a new DataTable
by combining the columns
of the DataTable
objects in ...
.
rbind(...)
: Creates a new DataTable
by combining the rows of
the DataTable
objects in ...
.
In the code snippets below, x
is a DataTable object.
x[i, j, drop=TRUE]
:
Return a new DataTable object made of the selected rows and columns. For
single column selection, the drop
argument specifies whether or not
to coerce the returned sequence to a standard vector.
head(x, n = 6L)
:
If n
is non-negative, returns the first n rows of the DataTable
object.
If n
is negative, returns all but the last abs(n)
rows of
the DataTable object.
length(x)
:
Return the number of columns in the DataTable object.
seqselect(x, start=NULL, end=NULL, width=NULL)
:
Similar to window
, except that multiple subsequences can be
requested. The requested subsequences are concatenated.
seqselect(x, start=NULL, end=NULL, width=NULL) <- value
:
Similar to window<-
, except that multiple consecutive subsequences
can be replaced by a value
that spans those windows.
subset(x, subset, select, drop = FALSE)
:
Return a new DataTable object using:
[
indexing operator.tail(x, n = 6L)
:
If n
is non-negative, returns the last n rows of the DataTable
object.
If n
is negative, returns all but the first abs(n)
rows of
the DataTable object.
window(x, start = NA, end = NA, width = NA, frequency = NULL, delta = NULL, ...)
:
Extract the subsequence window from the DataTable object using:
start
, end
, width
frequency
, delta
"["
operator.
window(x, start = NA, end = NA, width = NA, keepLength = TRUE) <- 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)
, be coercible to class(x)
, or be NULL
.
If keepLength
is TRUE
, the number of rows of value
are repeated to create a DataTable with the same number of rows as the
width of the subsequence window it is replacing.
If keepLength
is FALSE
, this replacement method can modify
the number of rows of x
, depending on how the number of rows of the
left subsequence window compares to the number of rows of value
.
In the code snippets below, x
is a DataTable object.
aggregate(x, by, FUN, start = NULL, end = NULL, width = NULL,
frequency = NULL, delta = NULL, ..., simplify = TRUE))
:
Generates summaries on the specified windows and returns the result in a
convenient form:
by
start
, end
, and
width
methods.FUN
match.fun
, to be
applied to each window of x
.start
, end
, width
by
is missing, then must supply two of the
three.frequency
, delta
FUN
.simplify
by(data, INDICES, FUN, ..., simplify = TRUE)
:
Apply FUN
to each group of data
, a DataTable
,
formed by the factor (or list of factors) INDICES
. Exactly
the same contract as as.data.frame
.
as.env(x, enclos = parent.frame())
:
Creates an environment from x
with a symbol for each
colnames(x)
. The values are not actually copied into the
environment. Rather, they are dynamically bound using
makeActiveBinding
. This prevents unnecessary copying
of the data from the external vectors into R vectors. The values
are cached, so that the data is not copied every time the symbol
is accessed.
DataTable-stats for statistical functionality, like fitting
regression models,
DataFrame-class for an implementation that mimics
data.frame
,
Sequence-class
showClass("DataTable") # shows (some of) the known subclasses