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slasq6.f(3) LAPACK slasq6.f(3)

NAME

slasq6.f -

SYNOPSIS

Functions/Subroutines


subroutine slasq6 (I0, N0, Z, PP, DMIN, DMIN1, DMIN2, DN, DNM1, DNM2)
SLASQ6 computes one dqd transform in ping-pong form. Used by sbdsqr and sstegr.

Function/Subroutine Documentation

subroutine slasq6 (integerI0, integerN0, real, dimension( * )Z, integerPP, realDMIN, realDMIN1, realDMIN2, realDN, realDNM1, realDNM2)

SLASQ6 computes one dqd transform in ping-pong form. Used by sbdsqr and sstegr.

Purpose:


SLASQ6 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 REAL 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 REAL
Minimum value of d.

DMIN1


DMIN1 is REAL
Minimum value of d, excluding D( N0 ).

DMIN2


DMIN2 is REAL
Minimum value of d, excluding D( N0 ) and D( N0-1 ).

DN


DN is REAL
d(N0), the last value of d.

DNM1


DNM1 is REAL
d(N0-1).

DNM2


DNM2 is REAL
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 slasq6.f.

Author

Generated automatically by Doxygen for LAPACK from the source code.

Tue Sep 25 2012 Version 3.4.2