symm.info {fastmatrix} | R Documentation |
Compact information to construct the symmetrizer matrix
Description
This function provides the information required to create the symmetrizer matrix.
Usage
symm.info(n = 1)
Arguments
n |
order of the symmetrizer matrix. |
Details
This function returns a list containing vectors that represent an element of the
symmetrizer matrix and is accesed by the indexes in vectors row
, col
and values contained in val
. This information is used by function symm.prod
to do some operations involving the symmetrizer matrix without forming it. This
information also can be obtained using function symmetrizer
.
Value
A list containing the following elements:
row |
vector of indexes, each entry represents the row index of the symmetrizer matrix. |
col |
vector of indexes, each entry represents the column index of the symmetrizer matrix. |
val |
vector of values, each entry represents the value of the symmetrizer matrix
at element given by |
order |
order of the symmetrizer matrix. |
See Also
Examples
z <- symm.info(n = 3)
z # elements in symmetrizer matrix of order 3
N3 <- symmetrizer(n = 3, matrix = TRUE)
N3 # only recommended if n is very small