tridiag_complex.hpp File Reference

Precomputed LU Thomas solver for constant-coefficient complex tridiagonal systems. More...

#include "core/types.hpp"
#include <complex>
#include <vector>

Go to the source code of this file.

Classes
struct	num::ComplexTriDiag
	Constant-coefficient complex tridiagonal solver (precomputed LU). More...

Namespaces
namespace	num

Detailed Description

Precomputed LU Thomas solver for constant-coefficient complex tridiagonal systems.

Solves the n x n system:

a*x[k-1] + b*x[k] + c*x[k+1] = d[k], k = 0 .. n-1

with Dirichlet boundary conditions x[-1] = x[n] = 0.

Because a, b, c are the same for every row the LU factorization depends only on the coefficients, not on d. Factor once, then call solve() for each new right-hand side in O(n).

Typical use: Crank-Nicolson kinetic sweeps in the TDSE solver, where a = c = -i*alpha and b = 1 + 2i*alpha for some real alpha.

Definition in file tridiag_complex.hpp.