LAPACK
3.4.2
LAPACK: Linear Algebra PACKage

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Functions/Subroutines  
subroutine  dlasq6 (I0, N0, Z, PP, DMIN, DMIN1, DMIN2, DN, DNM1, DNM2) 
DLASQ6 computes one dqd transform in pingpong form. Used by sbdsqr and sstegr. 
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 pingpong form. Used by sbdsqr and sstegr.
Download DLASQ6 + dependencies [TGZ] [ZIP] [TXT]DLASQ6 computes one dqd (shift equal to zero) transform in pingpong form, with protection against underflow and overflow.
[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( N01 ). 
[out]  DN  DN is DOUBLE PRECISION d(N0), the last value of d. 
[out]  DNM1  DNM1 is DOUBLE PRECISION d(N01). 
[out]  DNM2  DNM2 is DOUBLE PRECISION d(N02). 
Definition at line 119 of file dlasq6.f.