Scroll to navigation

dlasq6.f(3) LAPACK dlasq6.f(3)

NAME

dlasq6.f -

SYNOPSIS

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 (integerI0, integerN0, double precision, dimension( * )Z, integerPP, double precisionDMIN, double precisionDMIN1, double precisionDMIN2, double precisionDN, double precisionDNM1, double precisionDNM2)

DLASQ6 computes one dqd transform in ping-pong form. Used by sbdsqr and sstegr.
Purpose: 
 DLASQ6 computes one dqd (shift equal to zero) transform in
 ping-pong form, with protection against underflow and overflow.
Parameters:
I0 
          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. EMIN is stored in Z(4*N0) to avoid
        an extra argument.
PP 
          PP is INTEGER
        PP=0 for ping, PP=1 for pong.
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(N0), the last value of d.
DNM1 
          DNM1 is DOUBLE PRECISION
        d(N0-1).
DNM2 
          DNM2 is DOUBLE PRECISION
        d(N0-2).
Author:
Univ. of Tennessee
Univ. of California Berkeley
Univ. of Colorado Denver
NAG Ltd.
Date:
September 2012
Definition at line 119 of file dlasq6.f.

Author

Generated automatically by Doxygen for LAPACK from the source code.
Wed Oct 15 2014 Version 3.4.2