R: Packed triangular dense matrices

dtpMatrix-class {Matrix} | R Documentation

## Packed triangular dense matrices

### Description

The `"dtpMatrix"` class is the class of triangular, dense, numeric matrices in packed storage. The `"dtrMatrix"` class is the same except in nonpacked storage.

### Objects from the Class

Objects can be created by calls of the form `new("dtpMatrix", ...)` or by coercion from other classes of matrices.

### Slots

`uplo`:

  Object of class `"character"`. Must be either "U", for upper triangular, and "L", for lower triangular.

`diag`:

  Object of class `"character"`. Must be either `"U"`, for unit triangular (diagonal is all ones), or `"N"`; see `triangularMatrix`.

`x`:

  Object of class `"numeric"`. The numeric values that constitute the matrix, stored in column-major order. For a packed square matrix of dimension d * d, `length(x)` is of length d(d+1)/2 (also when `diag == "U"`!).

`Dim`,`Dimnames`:

  The dimension (a length-2 `"integer"`) and corresponding names (or `NULL`), inherited from the `Matrix`, see there.

### Extends

Class `"ddenseMatrix"`, directly. Class `"triangularMatrix"`, directly. Class `"dMatrix"` and more by class `"ddenseMatrix"` etc, see the examples.

### Methods

%*%

  `signature(x = "dtpMatrix", y = "dgeMatrix")`: Matrix multiplication; ditto for several other signature combinations, see `showMethods("%*%", class = "dtpMatrix")`.

coerce

  `signature(from = "dtpMatrix", to = "dtrMatrix")`

coerce

  `signature(from = "dtpMatrix", to = "matrix")`

determinant

  `signature(x = "dtpMatrix", logarithm = "missing")`: ...

determinant

  `signature(x = "dtpMatrix", logarithm = "logical")`: ...

diag

  `signature(x = "dtpMatrix")`: ...

norm

  `signature(x = "dtpMatrix", type = "character")`: ...

norm

  `signature(x = "dtpMatrix", type = "missing")`: ...

rcond

  `signature(x = "dtpMatrix", norm = "character")`: ...

rcond

  `signature(x = "dtpMatrix", norm = "missing")`: ...

solve

  `signature(a = "dtpMatrix", b = "missing")`: ...

solve

  `signature(a = "dtpMatrix", b = "matrix")`: ...

t

  `signature(x = "dtpMatrix")`: ...

unpack

  `signature(x = "dtpMatrix")`: ...

### See Also

Class `dtrMatrix`

### Examples

    showClass("dtrMatrix")

    example("dtrMatrix-class")
    (p1 <- as(T2, "dtpMatrix"))
    str(p1)
    (pp <- as(T, "dtpMatrix"))
    stopifnot(length(p1@x) == 3, length(pp@x) == 3,
              p1 @ uplo == T2 @ uplo, pp @ uplo == T @ uplo)

[Package Matrix version 1.0-6 Index]