LARTGS: generates a plane rotation designed to introduce a bulge in Golub-Reinsch-style implicit QR iteration for the bidiagonal SVD problem. X and Y are the top-row entries, and SIGMA is the shift. The computed CS and SN define a plane rotation satisfying [ CS SN ] . [ X^2 - SIGMA ] = [ R ], [ -SN CS ] [ X * Y ] [ 0 ] with R nonnegative. If X^2 - SIGMA and X * Y are 0, then the rotation is by PI/2. More...

Public Member Functions
pure subroutine	dlartgs (x, y, sigma, cs, sn)

	la_dlartgs

	la_qlartgs

pure subroutine	slartgs (x, y, sigma, cs, sn)

	la_slartgs

Detailed Description

LARTGS: generates a plane rotation designed to introduce a bulge in Golub-Reinsch-style implicit QR iteration for the bidiagonal SVD problem. X and Y are the top-row entries, and SIGMA is the shift. The computed CS and SN define a plane rotation satisfying [ CS SN ] . [ X^2 - SIGMA ] = [ R ], [ -SN CS ] [ X * Y ] [ 0 ] with R nonnegative. If X^2 - SIGMA and X * Y are 0, then the rotation is by PI/2.

Member Function/Subroutine Documentation

◆ dlartgs()

pure subroutine la_lapack::lartgs::dlartgs	(	real(dp), intent(in)	x,
		real(dp), intent(in)	y,
		real(dp), intent(in)	sigma,
		real(dp), intent(out)	cs,
		real(dp), intent(out)	sn
	)

◆ la_dlartgs()

la_lapack::lartgs::la_dlartgs

◆ la_qlartgs()

la_lapack::lartgs::la_qlartgs

◆ la_slartgs()

la_lapack::lartgs::la_slartgs

◆ slartgs()

pure subroutine la_lapack::lartgs::slartgs	(	real(sp), intent(in)	x,
		real(sp), intent(in)	y,
		real(sp), intent(in)	sigma,
		real(sp), intent(out)	cs,
		real(sp), intent(out)	sn
	)

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

la_lapack.f90