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[matrix] Annotation of /pkg/man/lsparseMatrix-classes.Rd
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Annotation of /pkg/man/lsparseMatrix-classes.Rd

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1 : bates 723 \name{lsparseMatrix-classes}
2 : bates 720 \docType{class}
3 : bates 723 \alias{lsparseMatrix-class}
4 : bates 720 \alias{lgCMatrix-class}
5 : bates 722 \alias{ltCMatrix-class}
6 :     \alias{lsCMatrix-class}
7 : bates 723 \alias{lgRMatrix-class}
8 :     \alias{ltRMatrix-class}
9 :     \alias{lsRMatrix-class}
10 :     \alias{lgTMatrix-class}
11 :     \alias{ltTMatrix-class}
12 :     \alias{lsTMatrix-class}
13 : bates 720 \alias{\%*\%,lgCMatrix,lgCMatrix-method}
14 : bates 723 \alias{coerce,dgCMatrix,lgCMatrix-method}
15 : bates 725 \alias{coerce,lgCMatrix,dgCMatrix-method}
16 :     \alias{coerce,lsCMatrix,dsCMatrix-method}
17 : bates 723 \alias{crossprod,lgCMatrix,missing-method}
18 : bates 720 \alias{t,lgCMatrix-method}
19 : bates 723 \alias{tcrossprod,lgCMatrix-method}
20 :     \title{Sparse logical matrices}
21 :     \description{The \code{lsparseMatrix} class is a virtual class of sparse
22 :     matrices with \code{TRUE}/\code{FALSE} entries. Only the positions of the
23 :     elements that are \code{TRUE} are stored. These can be stored in the
24 :     ``triplet'' form (classes \code{lgTMatrix}, \code{lsTMatrix}, and
25 :     \code{ltTMatrix} which really contain pairs, not triplets) or in
26 :     compressed column-oriented form (classes \code{lgCMatrix}, \code{lsCMatrix}, and
27 :     \code{ltCMatrix}) or in compressed row-oriented form (classes \code{lgRMatrix}, \code{lsRMatrix}, and
28 :     \code{ltRMatrix}). The second
29 :     letter in the name of these non-virtual classes indicates
30 :     \code{g}eneral, \code{s}ymmetric, or \code{t}riangular.
31 :     }
32 : bates 720 \section{Objects from the Class}{
33 : bates 723 Objects can be created by calls of the form \code{new("lgCMatrix",
34 :     ...)} and so on. More frequently objects are created by coercion of
35 :     a numeric sparse matrix to the logical form for use in
36 :     the symbolic analysis phase
37 :     of an algorithm involving sparse matrices. Such algorithms often
38 :     involve two phases: a symbolic phase wherein the positions of the
39 :     non-zeros in the result are determined and a numeric phase wherein the
40 :     actual results are calculated. During the symbolic phase only the
41 :     positions of the non-zero elements in any operands are of interest,
42 :     hence any numeric sparse matrices can be treated as logical sparse
43 :     matrices.
44 : bates 720 }
45 :     \section{Slots}{
46 :     \describe{
47 : bates 722 \item{\code{uplo}:}{Object of class \code{"character"}. Must be
48 :     either "U", for upper triangular, and "L", for lower
49 :     triangular. Present in the triangular and symmetric classes but not
50 :     in the general class.}
51 :     \item{\code{diag}:}{Object of class \code{"character"}. Must be
52 :     either \code{"U"}, for unit triangular (diagonal is all ones), or
53 :     \code{"N"} for non-unit. The implicit diagonal elements are not
54 :     explicitly stored when \code{diag} is \code{"U"}. Present in the
55 :     triangular classes only.}
56 : bates 720 \item{\code{p}:}{Object of class \code{"integer"} of pointers, one
57 : bates 723 for each column (row), to the initial (zero-based) index of elements in
58 :     the column. Present in compressed column-oriented and compressed
59 :     row-oriented forms only.}
60 : bates 720 \item{\code{i}:}{Object of class \code{"integer"} of length nnzero
61 :     (number of non-zero elements). These are the row numbers for
62 : bates 723 each TRUE element in the matrix. All other elements are FALSE.
63 :     Present in triplet and compressed column-oriented forms only.}
64 :     \item{\code{j}:}{Object of class \code{"integer"} of length nnzero
65 :     (number of non-zero elements). These are the column numbers for
66 :     each TRUE element in the matrix. All other elements are FALSE.
67 :     Present in triplet and compressed column-oriented forms only.}
68 : bates 720 \item{\code{Dim}:}{Object of class \code{"integer"} - the dimensions
69 :     of the matrix.}
70 :     }
71 :     }
72 :     \section{Methods}{
73 :     \describe{
74 :     \item{coerce}{\code{signature(from = "dgCMatrix", to = "lgCMatrix")}}
75 :     \item{t}{\code{signature(x = "lgCMatrix")}: returns the transpose
76 :     of \code{x}}
77 :     }
78 :     }
79 :     %\references{}
80 :     %\author{}
81 : bates 723 %\note{}
82 : bates 720 \seealso{
83 : bates 722 \code{\link{dgCMatrix-class}}
84 : bates 720 }
85 :     %\examples{}
86 :     \keyword{classes}
87 :     \keyword{algebra}

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