dtrMatrix-class | R Documentation |

The `"dtrMatrix"`

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

class
is the same except in packed storage, see `pack()`

.

Objects can be created by calls of the form `new("dtrMatrix", ...)`

.

`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.`Dim`

:Object of class

`"integer"`

. The dimensions of the matrix which must be a two-element vector of non-negative integers.

Class `"ddenseMatrix"`

, directly.
Class `"triangularMatrix"`

, directly.
Class `"Matrix"`

and others, by class `"ddenseMatrix"`

.

Among others (such as matrix products, e.g. `?crossprod-methods`

),

- norm
`signature(x = "dtrMatrix", type = "character")`

: ..- rcond
`signature(x = "dtrMatrix", norm = "character")`

: ..- solve
`signature(a = "dtrMatrix", b = "....")`

: efficiently use a “forwardsolve” or`backsolve`

for a lower or upper triangular matrix, respectively, see also`solve-methods`

.- +, -, *, ..., ==, >=, ...
all the

`Ops`

group methods are available. When applied to two triangular matrices, these return a triangular matrix when easily possible.

Classes `ddenseMatrix`

, `dtpMatrix`

,
`triangularMatrix`

```
(m <- rbind(2:3, 0:-1))
(M <- as(m, "generalMatrix"))
(T <- as(M, "triangularMatrix")) # formally upper triangular
(T2 <- as(t(M), "triangularMatrix"))
stopifnot(T@uplo == "U", T2@uplo == "L", identical(T2, t(T)))
m <- matrix(0,4,4); m[upper.tri(m)] <- 1:6
(t1 <- Matrix(m+diag(,4)))
str(t1p <- pack(t1))
(t1pu <- diagN2U(t1p))
stopifnot(exprs = {
inherits(t1 , "dtrMatrix"); validObject(t1)
inherits(t1p, "dtpMatrix"); validObject(t1p)
inherits(t1pu,"dtCMatrix"); validObject(t1pu)
t1pu@x == 1:6
all(t1pu == t1p)
identical((t1pu - t1)@x, numeric())# sparse all-0
})
```

Embedding an R snippet on your website

Add the following code to your website.

For more information on customizing the embed code, read Embedding Snippets.