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

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