- determinant
`signature(x = "Matrix", logarithm = "missing")`

: and

- determinant
`signature(x = "Matrix", logarithm = "logical")`

:
compute the (\(\log\)) determinant of `x`

. The method
chosen depends on the actual Matrix class of `x`

. Note that
`det`

also works for all our matrices, calling the
appropriate `determinant()`

method. The `Matrix::det`

is an exact copy of `base::det`

, but in the correct
namespace, and hence calling the S4-aware version of
`determinant()`

.).

- diff
`signature(x = "Matrix")`

: As `diff()`

for traditional matrices, i.e., applying `diff()`

to each
column.

- dim
`signature(x = "Matrix")`

: extract matrix dimensions
`dim`

.

- dim<-
`signature(x = "Matrix", value = "ANY")`

: where
`value`

is integer of length 2. Allows to *reshape*
Matrix objects, but only when `prod(value) == prod(dim(x))`

.

- dimnames
`signature(x = "Matrix")`

: extract
`dimnames`

.

- dimnames<-
`signature(x = "Matrix", value = "list")`

: set
the `dimnames`

to a `list`

of length 2, see
`dimnames<-`

.

- length
`signature(x = "Matrix")`

: simply defined as
`prod(dim(x))`

(and hence of mode `"double"`

).

- show
`signature(object = "Matrix")`

: `show`

method for `print`

ing. For printing *sparse*
matrices, see `printSpMatrix`

.

- image
`signature(object = "Matrix")`

: draws an
`image`

of the matrix entries, using
`levelplot()`

from package lattice.

- head
`signature(object = "Matrix")`

: return only the
*“head”*, i.e., the first few rows.

- tail
`signature(object = "Matrix")`

: return only the
*“tail”*, i.e., the last few rows of the respective matrix.

%------------------------------------
- as.matrix, as.array
`signature(x = "Matrix")`

: the same as
`as(x, "matrix")`

; see also the note below.

- as.vector
`signature(x = "Matrix", mode = "missing")`

:
`as.vector(m)`

should be identical to ```
as.vector(as(m,
"matrix"))
```

, implemented more efficiently for some subclasses.

- as(x, "vector"), as(x, "numeric")
etc, similarly.

- coerce
`signature(from = "ANY", to = "Matrix")`

: This
relies on a correct `as.matrix()`

method for `from`

.