LAPACK  3.4.2 LAPACK: Linear Algebra PACKage
dlasq6.f File Reference

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## Functions/Subroutines

subroutine dlasq6 (I0, N0, Z, PP, DMIN, DMIN1, DMIN2, DN, DNM1, DNM2)
DLASQ6 computes one dqd transform in ping-pong form. Used by sbdsqr and sstegr.

## Function/Subroutine Documentation

 subroutine dlasq6 ( integer I0, integer N0, double precision, dimension( * ) Z, integer PP, double precision DMIN, double precision DMIN1, double precision DMIN2, double precision DN, double precision DNM1, double precision DNM2 )

DLASQ6 computes one dqd transform in ping-pong form. Used by sbdsqr and sstegr.

``` DLASQ6 computes one dqd (shift equal to zero) transform in
 [in] I0 ``` I0 is INTEGER First index.``` [in] N0 ``` N0 is INTEGER Last index.``` [in] Z ``` Z is DOUBLE PRECISION array, dimension ( 4*N ) Z holds the qd array. EMIN is stored in Z(4*N0) to avoid an extra argument.``` [in] PP ``` PP is INTEGER PP=0 for ping, PP=1 for pong.``` [out] DMIN ``` DMIN is DOUBLE PRECISION Minimum value of d.``` [out] DMIN1 ``` DMIN1 is DOUBLE PRECISION Minimum value of d, excluding D( N0 ).``` [out] DMIN2 ``` DMIN2 is DOUBLE PRECISION Minimum value of d, excluding D( N0 ) and D( N0-1 ).``` [out] DN ``` DN is DOUBLE PRECISION d(N0), the last value of d.``` [out] DNM1 ``` DNM1 is DOUBLE PRECISION d(N0-1).``` [out] DNM2 ``` DNM2 is DOUBLE PRECISION d(N0-2).```