lu: LU Decomposition.

In Fuzzy-Logix/AdapteR: Converts R syntax to SQL to provide fast analytics using in-database C++ library DB Lytix.

Description

The LU decomposition involves factorizing a matrix as the product of a lower triangular matrix L and an upper triangular matrix U. Permutation matrix is also provided in the output. If permutation matrix is not used in the decomposition, the output of permutation matrix is an identity matrix.

Usage

lu(object, ...)

Arguments

object	is of class FLMatrix
...	any additional arguments

Details

lu replicates the equivalent lu() generic function.
expand decomposes the compact form to a list of matrix factors.
The expand method returns L,U and P factors as a list of FLMatrices.

The decomposition is of the form A = P L U where typically all matrices are of size (n x n), and the matrix P is a permutation matrix, L is lower triangular and U is upper triangular.

Value

x	the FLVector form of "L" (unit lower triangular) and "U" (upper triangular) factors of the original matrix
perm	FLVector that describes the permutation applied to the rows of the original matrix
Dim	FLVector that gives the dimension of the original matrix
lower	FLMatrix representing the lower triangular matrix
upper	FLMatrix representing the upper triangular matrix
data_perm	FLMatrix representing the permutation matrix

Constraints

Input can only be with maximum dimension limitations of (1000 x 1000).

Examples

flmatrix <- FLMatrix("tblMatrixMulti", 5,"MATRIX_ID","ROW_ID","COL_ID","CELL_VAL")
FLLUobject <- lu(flmatrix)
listresult <- expand(FLLUobject)
listresult$L
listresult$U
listresult$P

Fuzzy-Logix/AdapteR documentation built on May 6, 2019, 5:07 p.m.