Provided by: liblapack-doc-man_3.5.0-2ubuntu1_all
NAME
slasq4.f -
SYNOPSIS
Functions/Subroutines subroutine slasq4 (I0, N0, Z, PP, N0IN, DMIN, DMIN1, DMIN2, DN, DN1, DN2, TAU, TTYPE, G) SLASQ4 computes an approximation to the smallest eigenvalue using values of d from the previous transform. Used by sbdsqr.
Function/Subroutine Documentation
subroutine slasq4 (integerI0, integerN0, real, dimension( * )Z, integerPP, integerN0IN, realDMIN, realDMIN1, realDMIN2, realDN, realDN1, realDN2, realTAU, integerTTYPE, realG) SLASQ4 computes an approximation to the smallest eigenvalue using values of d from the previous transform. Used by sbdsqr. Purpose: SLASQ4 computes an approximation TAU to the smallest eigenvalue using values of d from the previous transform. 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. 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 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(N) DN1 DN1 is REAL d(N-1) DN2 DN2 is REAL d(N-2) TAU TAU is REAL 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 SLASQ4. Author: Univ. of Tennessee Univ. of California Berkeley Univ. of Colorado Denver NAG Ltd. Date: September 2012 Further Details: CNST1 = 9/16 Definition at line 151 of file slasq4.f.
Author
Generated automatically by Doxygen for LAPACK from the source code.