com.eignex.koblas/sparse/host/basiclu/[host]BasicluBasisFactorization

BasicluBasisFactorization

class BasicluBasisFactorization : BasicluFactorization, F64BasisFactorization(source)

A host BASICLU basis whose factors follow a column replacement until BASICLU declines the update.

Properties

basis

open override var basis: F64SparseMatrix(source)

The square basis matrix represented by this factorization.

failedAt

open override val failedAt: Int

The pivot position that had no numerically acceptable candidate, or NOT_SINGULAR when the factorization succeeded.

open override val n: Int

The dimension of the factored matrix.

nnz

open override val nnz: Int

Nonzeros in the factors, the fill. Zero for a singular factorization, which has none.

rcond

open override val rcond: Double

A cheap pivot-quality estimate: min(abs(U(k, k))) / max(abs(U(k, k))). A small value warns that the factorization may be inaccurate; it is not a reciprocal condition-number estimate.

singular

open val singular: Boolean

Whether the factorization failed for want of a numerically acceptable pivot. Solving against one throws com.eignex.koblas.SingularMatrix rather than answering with infinities.

Functions

replaceColumn

open override fun replaceColumn(column: Int, entering: F64SparseVector): F64BasisFactorization(source)

Replace column of basis with entering and return the factorization of the resulting basis, which supersedes this factorization.

column must name a column of basis, and entering must have length n.

solve

open fun solve(b: DoubleArray, transpose: Boolean = false): DoubleArray

Solve B x = b, or Bᵀ x = b when transpose, into a fresh result.

solveInto

open override fun solveInto(b: DoubleArray, out: DoubleArray, transpose: Boolean = false, workspace: Workspace? = null): DoubleArray

Solve B x = b, or Bᵀ x = b when transpose, into out, which is returned. Allocates nothing when given a workspace. out may be b.