[BACK]Return to zlahqr.f CVS log [TXT] [DIR] Up to [local] / rpl / lapack / lapack

Diff for /rpl/lapack/lapack/zlahqr.f between versions 1.19 and 1.20

version 1.19, 2020/05/21 21:46:07 version 1.20, 2023/08/07 08:39:29
Line 171 Line 171
 *> \author Univ. of Colorado Denver  *> \author Univ. of Colorado Denver
 *> \author NAG Ltd.  *> \author NAG Ltd.
 *  *
 *> \date December 2016  
 *  
 *> \ingroup complex16OTHERauxiliary  *> \ingroup complex16OTHERauxiliary
 *  *
 *> \par Contributors:  *> \par Contributors:
Line 194 Line 192
 *  =====================================================================  *  =====================================================================
       SUBROUTINE ZLAHQR( WANTT, WANTZ, N, ILO, IHI, H, LDH, W, ILOZ,        SUBROUTINE ZLAHQR( WANTT, WANTZ, N, ILO, IHI, H, LDH, W, ILOZ,
      $                   IHIZ, Z, LDZ, INFO )       $                   IHIZ, Z, LDZ, INFO )
         IMPLICIT NONE
 *  *
 *  -- LAPACK auxiliary routine (version 3.7.0) --  *  -- LAPACK auxiliary routine --
 *  -- LAPACK is a software package provided by Univ. of Tennessee,    --  *  -- LAPACK is a software package provided by Univ. of Tennessee,    --
 *  -- Univ. of California Berkeley, Univ. of Colorado Denver and NAG Ltd..--  *  -- Univ. of California Berkeley, Univ. of Colorado Denver and NAG Ltd..--
 *     December 2016  
 *  *
 *     .. Scalar Arguments ..  *     .. Scalar Arguments ..
       INTEGER            IHI, IHIZ, ILO, ILOZ, INFO, LDH, LDZ, N        INTEGER            IHI, IHIZ, ILO, ILOZ, INFO, LDH, LDZ, N
Line 218 Line 216
       PARAMETER          ( RZERO = 0.0d0, RONE = 1.0d0, HALF = 0.5d0 )        PARAMETER          ( RZERO = 0.0d0, RONE = 1.0d0, HALF = 0.5d0 )
       DOUBLE PRECISION   DAT1        DOUBLE PRECISION   DAT1
       PARAMETER          ( DAT1 = 3.0d0 / 4.0d0 )        PARAMETER          ( DAT1 = 3.0d0 / 4.0d0 )
         INTEGER            KEXSH
         PARAMETER          ( KEXSH = 10 )
 *     ..  *     ..
 *     .. Local Scalars ..  *     .. Local Scalars ..
       COMPLEX*16         CDUM, H11, H11S, H22, SC, SUM, T, T1, TEMP, U,        COMPLEX*16         CDUM, H11, H11S, H22, SC, SUM, T, T1, TEMP, U,
Line 225 Line 225
       DOUBLE PRECISION   AA, AB, BA, BB, H10, H21, RTEMP, S, SAFMAX,        DOUBLE PRECISION   AA, AB, BA, BB, H10, H21, RTEMP, S, SAFMAX,
      $                   SAFMIN, SMLNUM, SX, T2, TST, ULP       $                   SAFMIN, SMLNUM, SX, T2, TST, ULP
       INTEGER            I, I1, I2, ITS, ITMAX, J, JHI, JLO, K, L, M,        INTEGER            I, I1, I2, ITS, ITMAX, J, JHI, JLO, K, L, M,
      $                   NH, NZ       $                   NH, NZ, KDEFL
 *     ..  *     ..
 *     .. Local Arrays ..  *     .. Local Arrays ..
       COMPLEX*16         V( 2 )        COMPLEX*16         V( 2 )
Line 315 Line 315
 *  *
       ITMAX = 30 * MAX( 10, NH )        ITMAX = 30 * MAX( 10, NH )
 *  *
   *     KDEFL counts the number of iterations since a deflation
   *
         KDEFL = 0
   *
 *     The main loop begins here. I is the loop index and decreases from  *     The main loop begins here. I is the loop index and decreases from
 *     IHI to ILO in steps of 1. Each iteration of the loop works  *     IHI to ILO in steps of 1. Each iteration of the loop works
 *     with the active submatrix in rows and columns L to I.  *     with the active submatrix in rows and columns L to I.
Line 374 Line 378
 *  *
          IF( L.GE.I )           IF( L.GE.I )
      $      GO TO 140       $      GO TO 140
            KDEFL = KDEFL + 1
 *  *
 *        Now the active submatrix is in rows and columns L to I. If  *        Now the active submatrix is in rows and columns L to I. If
 *        eigenvalues only are being computed, only the active submatrix  *        eigenvalues only are being computed, only the active submatrix
Line 384 Line 389
             I2 = I              I2 = I
          END IF           END IF
 *  *
          IF( ITS.EQ.10 ) THEN           IF( MOD(KDEFL,2*KEXSH).EQ.0 ) THEN
 *  *
 *           Exceptional shift.  *           Exceptional shift.
 *  *
             S = DAT1*ABS( DBLE( H( L+1, L ) ) )              S = DAT1*ABS( DBLE( H( I, I-1 ) ) )
             T = S + H( L, L )              T = S + H( I, I )
          ELSE IF( ITS.EQ.20 ) THEN           ELSE IF( MOD(KDEFL,KEXSH).EQ.0 ) THEN
 *  *
 *           Exceptional shift.  *           Exceptional shift.
 *  *
             S = DAT1*ABS( DBLE( H( I, I-1 ) ) )              S = DAT1*ABS( DBLE( H( L+1, L ) ) )
             T = S + H( I, I )              T = S + H( L, L )
          ELSE           ELSE
 *  *
 *           Wilkinson's shift.  *           Wilkinson's shift.
Line 557 Line 562
 *     H(I,I-1) is negligible: one eigenvalue has converged.  *     H(I,I-1) is negligible: one eigenvalue has converged.
 *  *
       W( I ) = H( I, I )        W( I ) = H( I, I )
   *     reset deflation counter
         KDEFL = 0
 *  *
 *     return to start of the main loop with new value of I.  *     return to start of the main loop with new value of I.
 *  *
Removed from v.1.19  
changed lines
  Added in v.1.20

CVSweb interface <joel.bertrand@systella.fr>