sgCMatrix-class {arulesSequences} | R Documentation |

## Class "sgCMatrix" – Sparse Ordered Lists of Symbols

### Description

Sparse pseudo matrices in column-compressed form for storing ordered
*lists* of symbols.

### Objects from the Class

Most frequently, an object is created upon creation of an object of
class `sequences`

or

`sequencerules`

.

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

.

### Slots

`p`

:an integer vector of length the number of columns
in the matrix plus one. These are *zero-based pointers* into
`i`

, i.e. to the first element of a list. However, note that
the last element contains the number of elements of `i`

.

`i`

:an integer vector of length the number of non-zero
elements in the matrix. These are *zero-based* symbol
indexes, i.e. pointers into the row names if such exist.

`Dim`

:an integer vector representing the number of symbols
and the number of lists.

`Dimnames`

:a list with components for symbol and
*list* labels.

`factors`

:unused, for compatibility with package
Matrix only.

### Methods

`coerce`

`signature(from = "sgCMatrix", to = "list")`

`coerce`

`signature(from = "list", to = "sgCMatrix")`

`coerce`

`signature(from = "ngCMatrix", to = "sgCMatrix")`

`dim`

`signature(x = "sgCMatrix")`

`dimnames`

`signature(x = "sgCMatrix")`

`dimnames<-`

`signature(x = "sgCMatrix", value = "ANY")`

`show`

`signature(x = "sgCMatrix")`

### Note

The number of rows can be larger than the number of symbols actually
occurring. Thus `i`

need not be recoded upon subsetting or two
collections of lists with the same index base can be easily combined
(column or *row*-wise).

Many of the *methods* of this class implemented in C are
currently not interfaced as R methods.

### Author(s)

Christian Buchta

### See Also

Class
`sequences`

,
`timedsequences`

,
`sequencerules`

.

### Examples

## 3 example sequences
x <- list("01" = list(c("A","B"), "C"),
"02" = list("C"),
"03" = list("B", "B"))
## uses paste
s <- as(x, "sgCMatrix")
s
##
dim(s)
dimnames(s)

[Package

*arulesSequences* version 0.2-25

Index]