reverse.kronecker function

Reverses the matrices in a Kronecker product

This function takes a matrix that is Kronecker product $A \otimes B$

(Definition 3.5), where $A$ is $P x Q$ and $B$ is $N x M$, and outputs the matrix $B \otimes A$.

reverse.kronecker(ab, p, qq)

Arguments

• ab: The $(NP) x (QM)$ matrix $A \otimes B$.
• p: The number of rows of $A$.
• qq: The number of columns of $A$.

Returns

The $(NP) x (QM)$ matrix $B \otimes A$.

Examples

# Create matrices
(A <- diag(1, 3))
(B <- matrix(1:6, ncol = 2))

# Perform kronecker
(kron <- kronecker(A, B))

# Perform reverse kronecker product
(reverse.kronecker(kron, 3, 3))

# Perform kronecker again
(kron2 <- kronecker(B, A))

See Also

kronecker