LAGTS: may be used to solve one of the systems of equations (T - lambda*I)*x = y or (T - lambda*I)**T*x = y, where T is an n by n tridiagonal matrix, for x, following the factorization of (T - lambda*I) as (T - lambda*I) = P*L*U , by routine DLAGTF. The choice of equation to be solved is controlled by the argument JOB, and in each case there is an option to perturb zero or very small diagonal elements of U, this option being intended for use in applications such as inverse iteration. More...

Public Member Functions
pure subroutine	dlagts (job, n, a, b, c, d, in, y, tol, info)

	la_dlagts

	la_qlagts

pure subroutine	slagts (job, n, a, b, c, d, in, y, tol, info)

	la_slagts

Detailed Description

LAGTS: may be used to solve one of the systems of equations (T - lambda*I)*x = y or (T - lambda*I)**T*x = y, where T is an n by n tridiagonal matrix, for x, following the factorization of (T - lambda*I) as (T - lambda*I) = P*L*U , by routine DLAGTF. The choice of equation to be solved is controlled by the argument JOB, and in each case there is an option to perturb zero or very small diagonal elements of U, this option being intended for use in applications such as inverse iteration.

Member Function/Subroutine Documentation

◆ dlagts()

pure subroutine la_lapack::lagts::dlagts	(	integer(ilp), intent(in)	job,
		integer(ilp), intent(in)	n,
		real(dp), dimension(*), intent(in)	a,
		real(dp), dimension(*), intent(in)	b,
		real(dp), dimension(*), intent(in)	c,
		real(dp), dimension(*), intent(in)	d,
		integer(ilp), dimension(*), intent(in)	in,
		real(dp), dimension(*), intent(inout)	y,
		real(dp), intent(inout)	tol,
		integer(ilp), intent(out)	info
	)

◆ la_dlagts()

la_lapack::lagts::la_dlagts

◆ la_qlagts()

la_lapack::lagts::la_qlagts

◆ la_slagts()

la_lapack::lagts::la_slagts

◆ slagts()

pure subroutine la_lapack::lagts::slagts	(	integer(ilp), intent(in)	job,
		integer(ilp), intent(in)	n,
		real(sp), dimension(*), intent(in)	a,
		real(sp), dimension(*), intent(in)	b,
		real(sp), dimension(*), intent(in)	c,
		real(sp), dimension(*), intent(in)	d,
		integer(ilp), dimension(*), intent(in)	in,
		real(sp), dimension(*), intent(inout)	y,
		real(sp), intent(inout)	tol,
		integer(ilp), intent(out)	info
	)

The documentation for this interface was generated from the following file:

la_lapack.f90