diag.tensor {tensorA}

Creates a "diagonal" tensor

Description

The diagonal tensor is the tensor equivalent of the diagonal matrix.

Usage

diag.tensor(X,mark="'",dn=NULL,by=NULL)

Arguments

X

a tensor containing the diagonal entries.

mark

a character to be concatenated to the names of the row dimensions to get the column dimension names

dn

dimnames which are used twice

by

The diagonal tensor is created for each level of the indices in by.

Details

E_{i_1\ldots i_n j_1\ldots j_n}=\delta_{i_1j_1}\ldots\delta_{i_nj_n}

Value

a tensor with dimension c(dim(X),mark(dim(X),mark))

Author(s)

K. Gerald van den Boogaart

See Also

to.tensor

Examples

A <- to.tensor(1:4,c(a=2,b=2))
diag.tensor(A)
diag.tensor(A,by="b")