Triangular Dense Logical Matrices

The "ntrMatrix" class is the class of triangular, dense, logical matrices in nonpacked storage. The "ntpMatrix" class is the same except in packed storage.

Slots

x:

Object of class "logical". The logical values that constitute the matrix, stored in column-major order.

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.

Dim,Dimnames:

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

factors:

Object of class "list". A named list of factorizations that have been computed for the matrix.

Extends

"ntrMatrix" extends class "ngeMatrix", directly, whereas
"ntpMatrix" extends class "ndenseMatrix", directly.

Both extend Class "triangularMatrix", directly, and class "denseMatrix", "lMatrix" and others, indirectly, use showClass("nsyMatrix"), e.g., for details.

Methods

Currently, mainly t() and coercion methods (for as(.); use, e.g., showMethods(class="ntrMatrix") for details.

See also

Classes ngeMatrix, Matrix; function t

Examples

showClass("ntrMatrix")
#> Class "ntrMatrix" [package "Matrix"]
#> 
#> Slots:
#>                                                         
#> Name:        Dim  Dimnames         x      uplo      diag
#> Class:   integer      list   logical character character
#> 
#> Extends: 
#> Class "unpackedMatrix", directly
#> Class "ndenseMatrix", directly
#> Class "triangularMatrix", directly
#> Class "nMatrix", by class "ndenseMatrix", distance 2
#> Class "denseMatrix", by class "ndenseMatrix", distance 2
#> Class "Matrix", by class "triangularMatrix", distance 2

str(new("ntpMatrix"))
#> Formal class 'ntpMatrix' [package "Matrix"] with 5 slots
#>   ..@ uplo    : chr "U"
#>   ..@ Dim     : int [1:2] 0 0
#>   ..@ Dimnames:List of 2
#>   .. ..$ : NULL
#>   .. ..$ : NULL
#>   ..@ x       : logi(0) 
#>   ..@ diag    : chr "N"
(nutr <- as(upper.tri(matrix(, 4, 4)), "ndenseMatrix"))
#> 4 x 4 Matrix of class "ntrMatrix"
#>       [,1]  [,2]  [,3]  [,4]
#> [1,] FALSE  TRUE  TRUE  TRUE
#> [2,]     . FALSE  TRUE  TRUE
#> [3,]     .     . FALSE  TRUE
#> [4,]     .     .     . FALSE
str(nutp <- pack(nutr)) # packed matrix: only 10 = 4*(4+1)/2 entries
#> Formal class 'ntpMatrix' [package "Matrix"] with 5 slots
#>   ..@ uplo    : chr "U"
#>   ..@ Dim     : int [1:2] 4 4
#>   ..@ Dimnames:List of 2
#>   .. ..$ : NULL
#>   .. ..$ : NULL
#>   ..@ x       : logi [1:10] FALSE TRUE FALSE TRUE TRUE FALSE ...
#>   ..@ diag    : chr "N"
!nutp # the logical negation (is *not* logical triangular !)
#> 4 x 4 Matrix of class "ngeMatrix"
#>      [,1]  [,2]  [,3]  [,4]
#> [1,] TRUE FALSE FALSE FALSE
#> [2,] TRUE  TRUE FALSE FALSE
#> [3,] TRUE  TRUE  TRUE FALSE
#> [4,] TRUE  TRUE  TRUE  TRUE
## but this one is:
stopifnot(all.equal(nutp, pack(!!nutp)))