Linear algebra and solvers

The sparse factorizations and eigensolves the two-dimensional problems run on, and the reuse tricks that make a sweep affordable.

• The MUMPS complex-symmetric sparse backend
• TI energy-sweep symbolic reuse + the dense σ(E) cross-section curve
• Sparse shift-invert eigensolver

• The MUMPS complex-symmetric sparse backend — the complex-symmetric MUMPS backend.

• TI energy-sweep symbolic reuse + the dense σ(E) cross-section curve — reusing the symbolic factorization across an energy sweep.

• Sparse shift-invert eigensolver — the eigenpairs nearest a complex shift, for resonances that sit in the interior of the spectrum. Validated in 1-D only.