Convert a data.table to a matrix
Converts a data.table into a matrix, optionally using one
of the columns in the data.table as the matrix rownames.
## S3 method for class 'data.table' as.matrix(x, rownames=NULL, rownames.value=NULL, ...)
x |
a |
rownames |
optional, a single column name or column number to use as
the |
rownames.value |
optional, a vector of values to be used as the
|
... |
Required to be present because the generic 'as.matrix' generic has it. Arguments here are not currently used or passed on by this method. |
as.matrix is a generic function in base R. It dispatches to
as.matrix.data.table if its x argument is a data.table.
The method for data.tables will return a character matrix if there
are only atomic columns and any non-(numeric/logical/complex) column,
applying as.vector to factors and format to other
non-character columns. Otherwise, the usual coercion hierarchy (logical <
integer < double < complex) will be used, e.g., all-logical data frames
will be coerced to a logical matrix, mixed logical-integer will give an
integer matrix, etc.
A new matrix containing the contents of x.
DT <- data.table(A = letters[1:10], X = 1:10, Y = 11:20) as.matrix(DT) # character matrix as.matrix(DT, rownames = "A") as.matrix(DT, rownames = 1) as.matrix(DT, rownames = TRUE) setkey(DT, A) as.matrix(DT, rownames = TRUE)
Please choose more modern alternatives, such as Google Chrome or Mozilla Firefox.