clagtm.f.html

来自「famous linear algebra library (LAPACK) p」· HTML 代码 · 共 258 行 · 第 1/2 页

<span class="comment">*</span><span class="comment">
</span>      IF( ALPHA.EQ.ONE ) THEN
         IF( <a name="LSAME.113"></a><a href="lsame.f.html#LSAME.1">LSAME</a>( TRANS, <span class="string">'N'</span> ) ) THEN
<span class="comment">*</span><span class="comment">
</span><span class="comment">*</span><span class="comment">           Compute B := B + A*X
</span><span class="comment">*</span><span class="comment">
</span>            DO 60 J = 1, NRHS
               IF( N.EQ.1 ) THEN
                  B( 1, J ) = B( 1, J ) + D( 1 )*X( 1, J )
               ELSE
                  B( 1, J ) = B( 1, J ) + D( 1 )*X( 1, J ) +
     $                        DU( 1 )*X( 2, J )
                  B( N, J ) = B( N, J ) + DL( N-1 )*X( N-1, J ) +
     $                        D( N )*X( N, J )
                  DO 50 I = 2, N - 1
                     B( I, J ) = B( I, J ) + DL( I-1 )*X( I-1, J ) +
     $                           D( I )*X( I, J ) + DU( I )*X( I+1, J )
   50             CONTINUE
               END IF
   60       CONTINUE
         ELSE IF( <a name="LSAME.131"></a><a href="lsame.f.html#LSAME.1">LSAME</a>( TRANS, <span class="string">'T'</span> ) ) THEN
<span class="comment">*</span><span class="comment">
</span><span class="comment">*</span><span class="comment">           Compute B := B + A**T * X
</span><span class="comment">*</span><span class="comment">
</span>            DO 80 J = 1, NRHS
               IF( N.EQ.1 ) THEN
                  B( 1, J ) = B( 1, J ) + D( 1 )*X( 1, J )
               ELSE
                  B( 1, J ) = B( 1, J ) + D( 1 )*X( 1, J ) +
     $                        DL( 1 )*X( 2, J )
                  B( N, J ) = B( N, J ) + DU( N-1 )*X( N-1, J ) +
     $                        D( N )*X( N, J )
                  DO 70 I = 2, N - 1
                     B( I, J ) = B( I, J ) + DU( I-1 )*X( I-1, J ) +
     $                           D( I )*X( I, J ) + DL( I )*X( I+1, J )
   70             CONTINUE
               END IF
   80       CONTINUE
         ELSE IF( <a name="LSAME.149"></a><a href="lsame.f.html#LSAME.1">LSAME</a>( TRANS, <span class="string">'C'</span> ) ) THEN
<span class="comment">*</span><span class="comment">
</span><span class="comment">*</span><span class="comment">           Compute B := B + A**H * X
</span><span class="comment">*</span><span class="comment">
</span>            DO 100 J = 1, NRHS
               IF( N.EQ.1 ) THEN
                  B( 1, J ) = B( 1, J ) + CONJG( D( 1 ) )*X( 1, J )
               ELSE
                  B( 1, J ) = B( 1, J ) + CONJG( D( 1 ) )*X( 1, J ) +
     $                        CONJG( DL( 1 ) )*X( 2, J )
                  B( N, J ) = B( N, J ) + CONJG( DU( N-1 ) )*
     $                        X( N-1, J ) + CONJG( D( N ) )*X( N, J )
                  DO 90 I = 2, N - 1
                     B( I, J ) = B( I, J ) + CONJG( DU( I-1 ) )*
     $                           X( I-1, J ) + CONJG( D( I ) )*
     $                           X( I, J ) + CONJG( DL( I ) )*
     $                           X( I+1, J )
   90             CONTINUE
               END IF
  100       CONTINUE
         END IF
      ELSE IF( ALPHA.EQ.-ONE ) THEN
         IF( <a name="LSAME.171"></a><a href="lsame.f.html#LSAME.1">LSAME</a>( TRANS, <span class="string">'N'</span> ) ) THEN
<span class="comment">*</span><span class="comment">
</span><span class="comment">*</span><span class="comment">           Compute B := B - A*X
</span><span class="comment">*</span><span class="comment">
</span>            DO 120 J = 1, NRHS
               IF( N.EQ.1 ) THEN
                  B( 1, J ) = B( 1, J ) - D( 1 )*X( 1, J )
               ELSE
                  B( 1, J ) = B( 1, J ) - D( 1 )*X( 1, J ) -
     $                        DU( 1 )*X( 2, J )
                  B( N, J ) = B( N, J ) - DL( N-1 )*X( N-1, J ) -
     $                        D( N )*X( N, J )
                  DO 110 I = 2, N - 1
                     B( I, J ) = B( I, J ) - DL( I-1 )*X( I-1, J ) -
     $                           D( I )*X( I, J ) - DU( I )*X( I+1, J )
  110             CONTINUE
               END IF
  120       CONTINUE
         ELSE IF( <a name="LSAME.189"></a><a href="lsame.f.html#LSAME.1">LSAME</a>( TRANS, <span class="string">'T'</span> ) ) THEN
<span class="comment">*</span><span class="comment">
</span><span class="comment">*</span><span class="comment">           Compute B := B - A'*X
</span><span class="comment">*</span><span class="comment">
</span>            DO 140 J = 1, NRHS
               IF( N.EQ.1 ) THEN
                  B( 1, J ) = B( 1, J ) - D( 1 )*X( 1, J )
               ELSE
                  B( 1, J ) = B( 1, J ) - D( 1 )*X( 1, J ) -
     $                        DL( 1 )*X( 2, J )
                  B( N, J ) = B( N, J ) - DU( N-1 )*X( N-1, J ) -
     $                        D( N )*X( N, J )
                  DO 130 I = 2, N - 1
                     B( I, J ) = B( I, J ) - DU( I-1 )*X( I-1, J ) -
     $                           D( I )*X( I, J ) - DL( I )*X( I+1, J )
  130             CONTINUE
               END IF
  140       CONTINUE
         ELSE IF( <a name="LSAME.207"></a><a href="lsame.f.html#LSAME.1">LSAME</a>( TRANS, <span class="string">'C'</span> ) ) THEN
<span class="comment">*</span><span class="comment">
</span><span class="comment">*</span><span class="comment">           Compute B := B - A'*X
</span><span class="comment">*</span><span class="comment">
</span>            DO 160 J = 1, NRHS
               IF( N.EQ.1 ) THEN
                  B( 1, J ) = B( 1, J ) - CONJG( D( 1 ) )*X( 1, J )
               ELSE
                  B( 1, J ) = B( 1, J ) - CONJG( D( 1 ) )*X( 1, J ) -
     $                        CONJG( DL( 1 ) )*X( 2, J )
                  B( N, J ) = B( N, J ) - CONJG( DU( N-1 ) )*
     $                        X( N-1, J ) - CONJG( D( N ) )*X( N, J )
                  DO 150 I = 2, N - 1
                     B( I, J ) = B( I, J ) - CONJG( DU( I-1 ) )*
     $                           X( I-1, J ) - CONJG( D( I ) )*
     $                           X( I, J ) - CONJG( DL( I ) )*
     $                           X( I+1, J )
  150             CONTINUE
               END IF
  160       CONTINUE
         END IF
      END IF
      RETURN
<span class="comment">*</span><span class="comment">
</span><span class="comment">*</span><span class="comment">     End of <a name="CLAGTM.231"></a><a href="clagtm.f.html#CLAGTM.1">CLAGTM</a>
</span><span class="comment">*</span><span class="comment">
</span>      END

</pre>

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