F64SparseLinearAlgebra

Whether this backend can do work on this host. koblas's own implementations always can, so the default is true; a binding reports whether the library it calls resolved.

Whether this is koblas's own implementation rather than a binding to a host library. The compiled-in SIMD kernels are portable however fast they are; only something calling out counts as accelerated.

A short backend identifier for diagnostics (e.g. "reference").

Relative preference among the backends offered for one half (F64Blas, F64Decompositions, F64Kernels or a sparse counterpart). registerBackend picks the highest; the portable reference is 0.

Whether factorBasis answers with a factorization that updates its factors in place. When false a replacement costs a factorization, so a caller pacing its own refactorizations has nothing left to pace.

Factorize the square a into something solvable. A singular matrix comes back as a factorization reporting singular rather than as an exception, with a failedAt counting elimination steps rather than naming a column: the step that fails is the one with no acceptable pivot left, so there is no column of a to attribute it to.

Factor a simplex basis for column replacements.

A · x, or Aᵀ · x when transpose, into a fresh result.

In-place y = alpha · op(A) · x + beta · y, where op(A) is Aᵀ when transpose. Per BLAS convention beta == 0.0 overwrites y without reading it, so it may arrive uninitialized.

Factor a, reusing compatible state from previous when this backend can. The returned factorization supersedes previous, which must not be solved after this call. Backends that cannot reuse it answer as factor would.

solveInto into a fresh vector.

Solve A·x = b from f into out, Aᵀ·x = b when transpose. The work belongs to the factorization; this is here so the seam reads the same from the sparse side as com.eignex.koblas .dense.F64Decompositions.solveInto does from the dense one.

Solve op(T) · x = b in place, op transposing when transpose. x holds the right-hand side on entry and the solution on return. Only the lower or upper triangle of a is read, and unitDiag takes the diagonal as 1 without reading it, as the dense com.eignex.koblas.dense.F64Blas.trsv does.