kronecker-methods {Matrix} R Documentation

## Methods for Function 'kronecker()' in Package 'Matrix'

### Description

Computes Kronecker products for objects inheriting from `"Matrix"`.

In order to preserver sparseness, we treat `0 * NA` as `0`, not as `NA` as usually in R (and as used for the base function `kronecker`).

### Methods

kronecker

`signature(X = "Matrix", Y = "ANY")` .......

kronecker

`signature(X = "ANY", Y = "Matrix")` .......

kronecker

`signature(X = "diagonalMatrix", Y = "ANY")` .......

kronecker

`signature(X = "sparseMatrix", Y = "ANY")` .......

kronecker

`signature(X = "TsparseMatrix", Y = "TsparseMatrix")` .......

kronecker

`signature(X = "dgTMatrix", Y = "dgTMatrix")` .......

kronecker

`signature(X = "dtTMatrix", Y = "dtTMatrix")` .......

kronecker

`signature(X = "indMatrix", Y = "indMatrix")` .......

### Examples

```(t1 <- spMatrix(5,4, x= c(3,2,-7,11), i= 1:4, j=4:1)) #  5 x  4
(t2 <- kronecker(Diagonal(3, 2:4), t1))               # 15 x 12

## should also work with special-cased logical matrices
l3 <- upper.tri(matrix(,3,3))
M <- Matrix(l3)
(N <- as(M, "nsparseMatrix")) # "ntCMatrix" (upper triangular)
N2 <- as(N, "generalMatrix")  # (lost "t"riangularity)
MM <- kronecker(M,M)
NN <- kronecker(N,N) # "dtTMatrix" i.e. did keep
NN2 <- kronecker(N2,N2)
stopifnot(identical(NN,MM),
is(NN2, "sparseMatrix"), all(NN2 == NN),
is(NN, "triangularMatrix"))
```

[Package Matrix version 1.2-17 Index]