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来自「famous linear algebra library (LAPACK) p」· HTML 代码 · 共 479 行 · 第 1/3 页

</span>      LOGICAL            ILASCL, ILBSCL, ILV, ILVL, ILVR, LQUERY
      CHARACTER          CHTEMP
      INTEGER            ICOLS, IERR, IHI, IJOBVL, IJOBVR, ILEFT, ILO,
     $                   IN, IRIGHT, IROWS, IRWRK, ITAU, IWRK, JC, JR,
     $                   LWKMIN, LWKOPT
      DOUBLE PRECISION   ANRM, ANRMTO, BIGNUM, BNRM, BNRMTO, EPS,
     $                   SMLNUM, TEMP
      COMPLEX*16         X
<span class="comment">*</span><span class="comment">     ..
</span><span class="comment">*</span><span class="comment">     .. Local Arrays ..
</span>      LOGICAL            LDUMMA( 1 )
<span class="comment">*</span><span class="comment">     ..
</span><span class="comment">*</span><span class="comment">     .. External Subroutines ..
</span>      EXTERNAL           <a name="DLABAD.155"></a><a href="dlabad.f.html#DLABAD.1">DLABAD</a>, <a name="XERBLA.155"></a><a href="xerbla.f.html#XERBLA.1">XERBLA</a>, <a name="ZGEQRF.155"></a><a href="zgeqrf.f.html#ZGEQRF.1">ZGEQRF</a>, <a name="ZGGBAK.155"></a><a href="zggbak.f.html#ZGGBAK.1">ZGGBAK</a>, <a name="ZGGBAL.155"></a><a href="zggbal.f.html#ZGGBAL.1">ZGGBAL</a>, <a name="ZGGHRD.155"></a><a href="zgghrd.f.html#ZGGHRD.1">ZGGHRD</a>,
     $                   <a name="ZHGEQZ.156"></a><a href="zhgeqz.f.html#ZHGEQZ.1">ZHGEQZ</a>, <a name="ZLACPY.156"></a><a href="zlacpy.f.html#ZLACPY.1">ZLACPY</a>, <a name="ZLASCL.156"></a><a href="zlascl.f.html#ZLASCL.1">ZLASCL</a>, <a name="ZLASET.156"></a><a href="zlaset.f.html#ZLASET.1">ZLASET</a>, <a name="ZTGEVC.156"></a><a href="ztgevc.f.html#ZTGEVC.1">ZTGEVC</a>, <a name="ZUNGQR.156"></a><a href="zungqr.f.html#ZUNGQR.1">ZUNGQR</a>,
     $                   <a name="ZUNMQR.157"></a><a href="zunmqr.f.html#ZUNMQR.1">ZUNMQR</a>
<span class="comment">*</span><span class="comment">     ..
</span><span class="comment">*</span><span class="comment">     .. External Functions ..
</span>      LOGICAL            <a name="LSAME.160"></a><a href="lsame.f.html#LSAME.1">LSAME</a>
      INTEGER            <a name="ILAENV.161"></a><a href="hfy-index.html#ILAENV">ILAENV</a>
      DOUBLE PRECISION   <a name="DLAMCH.162"></a><a href="dlamch.f.html#DLAMCH.1">DLAMCH</a>, <a name="ZLANGE.162"></a><a href="zlange.f.html#ZLANGE.1">ZLANGE</a>
      EXTERNAL           <a name="LSAME.163"></a><a href="lsame.f.html#LSAME.1">LSAME</a>, <a name="ILAENV.163"></a><a href="hfy-index.html#ILAENV">ILAENV</a>, <a name="DLAMCH.163"></a><a href="dlamch.f.html#DLAMCH.1">DLAMCH</a>, <a name="ZLANGE.163"></a><a href="zlange.f.html#ZLANGE.1">ZLANGE</a>
<span class="comment">*</span><span class="comment">     ..
</span><span class="comment">*</span><span class="comment">     .. Intrinsic Functions ..
</span>      INTRINSIC          ABS, DBLE, DIMAG, MAX, SQRT
<span class="comment">*</span><span class="comment">     ..
</span><span class="comment">*</span><span class="comment">     .. Statement Functions ..
</span>      DOUBLE PRECISION   ABS1
<span class="comment">*</span><span class="comment">     ..
</span><span class="comment">*</span><span class="comment">     .. Statement Function definitions ..
</span>      ABS1( X ) = ABS( DBLE( X ) ) + ABS( DIMAG( X ) )
<span class="comment">*</span><span class="comment">     ..
</span><span class="comment">*</span><span class="comment">     .. Executable Statements ..
</span><span class="comment">*</span><span class="comment">
</span><span class="comment">*</span><span class="comment">     Decode the input arguments
</span><span class="comment">*</span><span class="comment">
</span>      IF( <a name="LSAME.178"></a><a href="lsame.f.html#LSAME.1">LSAME</a>( JOBVL, <span class="string">'N'</span> ) ) THEN
         IJOBVL = 1
         ILVL = .FALSE.
      ELSE IF( <a name="LSAME.181"></a><a href="lsame.f.html#LSAME.1">LSAME</a>( JOBVL, <span class="string">'V'</span> ) ) THEN
         IJOBVL = 2
         ILVL = .TRUE.
      ELSE
         IJOBVL = -1
         ILVL = .FALSE.
      END IF
<span class="comment">*</span><span class="comment">
</span>      IF( <a name="LSAME.189"></a><a href="lsame.f.html#LSAME.1">LSAME</a>( JOBVR, <span class="string">'N'</span> ) ) THEN
         IJOBVR = 1
         ILVR = .FALSE.
      ELSE IF( <a name="LSAME.192"></a><a href="lsame.f.html#LSAME.1">LSAME</a>( JOBVR, <span class="string">'V'</span> ) ) THEN
         IJOBVR = 2
         ILVR = .TRUE.
      ELSE
         IJOBVR = -1
         ILVR = .FALSE.
      END IF
      ILV = ILVL .OR. ILVR
<span class="comment">*</span><span class="comment">
</span><span class="comment">*</span><span class="comment">     Test the input arguments
</span><span class="comment">*</span><span class="comment">
</span>      INFO = 0
      LQUERY = ( LWORK.EQ.-1 )
      IF( IJOBVL.LE.0 ) THEN
         INFO = -1
      ELSE IF( IJOBVR.LE.0 ) THEN
         INFO = -2
      ELSE IF( N.LT.0 ) THEN
         INFO = -3
      ELSE IF( LDA.LT.MAX( 1, N ) ) THEN
         INFO = -5
      ELSE IF( LDB.LT.MAX( 1, N ) ) THEN
         INFO = -7
      ELSE IF( LDVL.LT.1 .OR. ( ILVL .AND. LDVL.LT.N ) ) THEN
         INFO = -11
      ELSE IF( LDVR.LT.1 .OR. ( ILVR .AND. LDVR.LT.N ) ) THEN
         INFO = -13
      END IF
<span class="comment">*</span><span class="comment">
</span><span class="comment">*</span><span class="comment">     Compute workspace
</span><span class="comment">*</span><span class="comment">      (Note: Comments in the code beginning &quot;Workspace:&quot; describe the
</span><span class="comment">*</span><span class="comment">       minimal amount of workspace needed at that point in the code,
</span><span class="comment">*</span><span class="comment">       as well as the preferred amount for good performance.
</span><span class="comment">*</span><span class="comment">       NB refers to the optimal block size for the immediately
</span><span class="comment">*</span><span class="comment">       following subroutine, as returned by <a name="ILAENV.226"></a><a href="hfy-index.html#ILAENV">ILAENV</a>. The workspace is
</span><span class="comment">*</span><span class="comment">       computed assuming ILO = 1 and IHI = N, the worst case.)
</span><span class="comment">*</span><span class="comment">
</span>      IF( INFO.EQ.0 ) THEN
         LWKMIN = MAX( 1, 2*N )
         LWKOPT = MAX( 1, N + N*<a name="ILAENV.231"></a><a href="hfy-index.html#ILAENV">ILAENV</a>( 1, <span class="string">'<a name="ZGEQRF.231"></a><a href="zgeqrf.f.html#ZGEQRF.1">ZGEQRF</a>'</span>, <span class="string">' '</span>, N, 1, N, 0 ) )
         LWKOPT = MAX( LWKOPT, N +
     $                 N*<a name="ILAENV.233"></a><a href="hfy-index.html#ILAENV">ILAENV</a>( 1, <span class="string">'<a name="ZUNMQR.233"></a><a href="zunmqr.f.html#ZUNMQR.1">ZUNMQR</a>'</span>, <span class="string">' '</span>, N, 1, N, 0 ) )
         IF( ILVL ) THEN
            LWKOPT = MAX( LWKOPT, N +
     $                    N*<a name="ILAENV.236"></a><a href="hfy-index.html#ILAENV">ILAENV</a>( 1, <span class="string">'<a name="ZUNGQR.236"></a><a href="zungqr.f.html#ZUNGQR.1">ZUNGQR</a>'</span>, <span class="string">' '</span>, N, 1, N, -1 ) )
         END IF
         WORK( 1 ) = LWKOPT
<span class="comment">*</span><span class="comment">
</span>         IF( LWORK.LT.LWKMIN .AND. .NOT.LQUERY )
     $      INFO = -15
      END IF
<span class="comment">*</span><span class="comment">
</span>      IF( INFO.NE.0 ) THEN
         CALL <a name="XERBLA.245"></a><a href="xerbla.f.html#XERBLA.1">XERBLA</a>( <span class="string">'<a name="ZGGEV.245"></a><a href="zggev.f.html#ZGGEV.1">ZGGEV</a> '</span>, -INFO )
         RETURN
      ELSE IF( LQUERY ) THEN
         RETURN
      END IF
<span class="comment">*</span><span class="comment">
</span><span class="comment">*</span><span class="comment">     Quick return if possible
</span><span class="comment">*</span><span class="comment">
</span>      IF( N.EQ.0 )
     $   RETURN
<span class="comment">*</span><span class="comment">
</span><span class="comment">*</span><span class="comment">     Get machine constants
</span><span class="comment">*</span><span class="comment">
</span>      EPS = <a name="DLAMCH.258"></a><a href="dlamch.f.html#DLAMCH.1">DLAMCH</a>( <span class="string">'E'</span> )*<a name="DLAMCH.258"></a><a href="dlamch.f.html#DLAMCH.1">DLAMCH</a>( <span class="string">'B'</span> )
      SMLNUM = <a name="DLAMCH.259"></a><a href="dlamch.f.html#DLAMCH.1">DLAMCH</a>( <span class="string">'S'</span> )
      BIGNUM = ONE / SMLNUM
      CALL <a name="DLABAD.261"></a><a href="dlabad.f.html#DLABAD.1">DLABAD</a>( SMLNUM, BIGNUM )
      SMLNUM = SQRT( SMLNUM ) / EPS
      BIGNUM = ONE / SMLNUM
<span class="comment">*</span><span class="comment">
</span><span class="comment">*</span><span class="comment">     Scale A if max element outside range [SMLNUM,BIGNUM]
</span><span class="comment">*</span><span class="comment">
</span>      ANRM = <a name="ZLANGE.267"></a><a href="zlange.f.html#ZLANGE.1">ZLANGE</a>( <span class="string">'M'</span>, N, N, A, LDA, RWORK )
      ILASCL = .FALSE.
      IF( ANRM.GT.ZERO .AND. ANRM.LT.SMLNUM ) THEN
         ANRMTO = SMLNUM
         ILASCL = .TRUE.
      ELSE IF( ANRM.GT.BIGNUM ) THEN
         ANRMTO = BIGNUM
         ILASCL = .TRUE.
      END IF
      IF( ILASCL )
     $   CALL <a name="ZLASCL.277"></a><a href="zlascl.f.html#ZLASCL.1">ZLASCL</a>( <span class="string">'G'</span>, 0, 0, ANRM, ANRMTO, N, N, A, LDA, IERR )
<span class="comment">*</span><span class="comment">
</span><span class="comment">*</span><span class="comment">     Scale B if max element outside range [SMLNUM,BIGNUM]
</span><span class="comment">*</span><span class="comment">
</span>      BNRM = <a name="ZLANGE.281"></a><a href="zlange.f.html#ZLANGE.1">ZLANGE</a>( <span class="string">'M'</span>, N, N, B, LDB, RWORK )
      ILBSCL = .FALSE.
      IF( BNRM.GT.ZERO .AND. BNRM.LT.SMLNUM ) THEN
         BNRMTO = SMLNUM
         ILBSCL = .TRUE.
      ELSE IF( BNRM.GT.BIGNUM ) THEN
         BNRMTO = BIGNUM
         ILBSCL = .TRUE.
      END IF
      IF( ILBSCL )
     $   CALL <a name="ZLASCL.291"></a><a href="zlascl.f.html#ZLASCL.1">ZLASCL</a>( <span class="string">'G'</span>, 0, 0, BNRM, BNRMTO, N, N, B, LDB, IERR )
<span class="comment">*</span><span class="comment">
</span><span class="comment">*</span><span class="comment">     Permute the matrices A, B to isolate eigenvalues if possible
</span><span class="comment">*</span><span class="comment">     (Real Workspace: need 6*N)
</span><span class="comment">*</span><span class="comment">
</span>      ILEFT = 1
      IRIGHT = N + 1
      IRWRK = IRIGHT + N
      CALL <a name="ZGGBAL.299"></a><a href="zggbal.f.html#ZGGBAL.1">ZGGBAL</a>( <span class="string">'P'</span>, N, A, LDA, B, LDB, ILO, IHI, RWORK( ILEFT ),
     $             RWORK( IRIGHT ), RWORK( IRWRK ), IERR )
<span class="comment">*</span><span class="comment">