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
.
nrow(x)
, ncol(x)
:
Get the number of rows and columns, respectively.
NROW(x)
, NCOL(x)
:
Same as nrow(x)
and ncol(x)
, respectively.
dim(x)
:
Length two integer vector defined as c(nrow(x), ncol(x))
.
rownames(x)
, colnames(x)
:
Get the names of the rows and columns, respectively.
dimnames(x)
:
Length two list of character vectors defined as
list(rownames(x), colnames(x))
.
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.
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
.
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.
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.
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.
subset(x, subset, select, drop = FALSE)
:
Return a new DataTable object using:
[
indexing operator.na.omit(object)
:
Returns a subset with incomplete cases removed.
na.exclude(object)
:
Returns a subset with incomplete cases removed (but to be
included with NAs in statistical results).
is.na(x)
:
Returns a logical matrix indicating which cells are missing.
complete.cases(x)
:
Returns a logical vector identifying which cases have no missing values.
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.
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