table of contents
other versions
- jessie 3.5.0-4
- jessie-backports 3.7.0-1~bpo8+1
- stretch 3.7.0-2
dlasq4.f(3) | LAPACK | dlasq4.f(3) |
NAME¶
dlasq4.f -SYNOPSIS¶
Functions/Subroutines¶
subroutine dlasq4 (I0, N0, Z, PP, N0IN, DMIN, DMIN1, DMIN2, DN, DN1, DN2, TAU, TTYPE, G)
Function/Subroutine Documentation¶
subroutine dlasq4 (integerI0, integerN0, double precision, dimension( * )Z, integerPP, integerN0IN, double precisionDMIN, double precisionDMIN1, double precisionDMIN2, double precisionDN, double precisionDN1, double precisionDN2, double precisionTAU, integerTTYPE, double precisionG)¶
DLASQ4 computes an approximation to the smallest eigenvalue using values of d from the previous transform. Used by sbdsqr. Purpose:DLASQ4 computes an approximation TAU to the smallest eigenvalue using values of d from the previous transform.
I0
Author:
I0 is INTEGER First index.N0
N0 is INTEGER Last index.Z
Z is DOUBLE PRECISION array, dimension ( 4*N ) Z holds the qd array.PP
PP is INTEGER PP=0 for ping, PP=1 for pong.N0IN
N0IN is INTEGER The value of N0 at start of EIGTEST.DMIN
DMIN is DOUBLE PRECISION Minimum value of d.DMIN1
DMIN1 is DOUBLE PRECISION Minimum value of d, excluding D( N0 ).DMIN2
DMIN2 is DOUBLE PRECISION Minimum value of d, excluding D( N0 ) and D( N0-1 ).DN
DN is DOUBLE PRECISION d(N)DN1
DN1 is DOUBLE PRECISION d(N-1)DN2
DN2 is DOUBLE PRECISION d(N-2)TAU
TAU is DOUBLE PRECISION This is the shift.TTYPE
TTYPE is INTEGER Shift type.G
G is REAL G is passed as an argument in order to save its value between calls to DLASQ4.
Univ. of Tennessee
Univ. of California Berkeley
Univ. of Colorado Denver
NAG Ltd.
Date:
September 2012
Further Details:
CNST1 = 9/16
Author¶
Generated automatically by Doxygen for LAPACK from the source code.Wed Oct 15 2014 | Version 3.4.2 |