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[matrix] View of /pkg/R/lgTMatrix.R
 [matrix] / pkg / R / lgTMatrix.R

# View of /pkg/R/lgTMatrix.R

Mon Sep 11 22:13:07 2006 UTC (12 years, 7 months ago) by maechler
File size: 1153 byte(s)
`new nMatrix and subclasses; lsparse change to have x slot; many consequences`
```#### Logical Sparse Matrices in triplet format

### contains = "lsparseMatrix"
###             ============= ---> superclass methods in ./lsparseMatrix.R

setAs("lgTMatrix", "matrix", # go via fast C code:
function(from) as(as(from, "lgCMatrix"), "matrix"))

setAs("matrix", "lgTMatrix",
function(from) {
stopifnot(is.logical(from))
TorNA <- is.na(from) | from
ij <- which(TorNA, arr.ind = TRUE) - 1:1
if(length(ij) == 0) ij <- matrix(ij, 0, 2)
new("lgTMatrix",
i = ij[,1],
j = ij[,2],
x = from[TorNA],
Dim = as.integer(dim(from)),
Dimnames = .M.DN(from))
})

setAs("lgTMatrix", "dgTMatrix",
function(from)
## more efficient than
## as(as(as(sM, "lgCMatrix"), "dgCMatrix"), "dgTMatrix")
new("dgTMatrix", i = from@i, j = from@j,
x = as.double(from@x),
## cannot copy factors, but can we use them?
Dim = from@Dim, Dimnames= from@Dimnames))

setMethod("t", signature(x = "lgTMatrix"),
function(x) new("lgTMatrix", i = x@j, j = x@i, x = x@x,
Dim = x@Dim[2:1],
Dimnames= x@Dimnames[2:1]),
valueClass = "lgTMatrix")
```