trunk/blas/dtrsm.f

      SUBROUTINE DTRSM ( SIDE, UPLO, TRANSA, DIAG, M, N, ALPHA, A, LDA,
*
************************************************************************
*
     $                   B, LDB )
*     .. Scalar Arguments ..
      CHARACTER*1        SIDE, UPLO, TRANSA, DIAG
      INTEGER            M, N, LDA, LDB
      DOUBLE PRECISION   ALPHA
*     .. Array Arguments ..
      DOUBLE PRECISION   A( LDA, * ), B( LDB, * )
*     ..
*
*  Purpose
*  =======
*
*  DTRSM  solves one of the matrix equations
*
*     op( A )*X = alpha*B,   or   X*op( A ) = alpha*B,
*
*  where alpha is a scalar, X and B are m by n matrices, A is a unit, or
*  non-unit,  upper or lower triangular matrix  and  op( A )  is one  of
*
*     op( A ) = A   or   op( A ) = A'.
*
*  The matrix X is overwritten on B.
*
*  Parameters
*  ==========
*
*  SIDE   - CHARACTER*1.
*           On entry, SIDE specifies whether op( A ) appears on the left
*           or right of X as follows:
*
*              SIDE = 'L' or 'l'   op( A )*X = alpha*B.
*
*              SIDE = 'R' or 'r'   X*op( A ) = alpha*B.
*
*           Unchanged on exit.
*
*  UPLO   - CHARACTER*1.
*           On entry, UPLO specifies whether the matrix A is an upper or
*           lower triangular matrix as follows:
*
*              UPLO = 'U' or 'u'   A is an upper triangular matrix.
*
*              UPLO = 'L' or 'l'   A is a lower triangular matrix.
*
*           Unchanged on exit.
*
*  TRANSA - CHARACTER*1.
*           On entry, TRANSA specifies the form of op( A ) to be used in
*           the matrix multiplication as follows:
*
*              TRANSA = 'N' or 'n'   op( A ) = A.
*
*              TRANSA = 'T' or 't'   op( A ) = A'.
*
*              TRANSA = 'C' or 'c'   op( A ) = A'.
*
*           Unchanged on exit.
*
*  DIAG   - CHARACTER*1.
*           On entry, DIAG specifies whether or not A is unit triangular
*           as follows:
*
*              DIAG = 'U' or 'u'   A is assumed to be unit triangular.
*
*              DIAG = 'N' or 'n'   A is not assumed to be unit
*                                  triangular.
*
*           Unchanged on exit.
*
*  M      - INTEGER.
*           On entry, M specifies the number of rows of B. M must be at
*           least zero.
*           Unchanged on exit.
*
*  N      - INTEGER.
*           On entry, N specifies the number of columns of B.  N must be
*           at least zero.
*           Unchanged on exit.
*
*  ALPHA  - DOUBLE PRECISION.
*           On entry,  ALPHA specifies the scalar  alpha. When  alpha is
*           zero then  A is not referenced and  B need not be set before
*           entry.
*           Unchanged on exit.
*
*  A      - DOUBLE PRECISION array of DIMENSION ( LDA, k ), where k is m
*           when  SIDE = 'L' or 'l'  and is  n  when  SIDE = 'R' or 'r'.
*           Before entry  with  UPLO = 'U' or 'u',  the  leading  k by k
*           upper triangular part of the array  A must contain the upper
*           triangular matrix  and the strictly lower triangular part of
*           A is not referenced.
*           Before entry  with  UPLO = 'L' or 'l',  the  leading  k by k
*           lower triangular part of the array  A must contain the lower
*           triangular matrix  and the strictly upper triangular part of
*           A is not referenced.
*           Note that when  DIAG = 'U' or 'u',  the diagonal elements of
*           A  are not referenced either,  but are assumed to be  unity.
*           Unchanged on exit.
*
*  LDA    - INTEGER.
*           On entry, LDA specifies the first dimension of A as declared
*           in the calling (sub) program.  When  SIDE = 'L' or 'l'  then
*           LDA  must be at least  max( 1, m ),  when  SIDE = 'R' or 'r'
*           then LDA must be at least max( 1, n ).
*           Unchanged on exit.
*
*  B      - DOUBLE PRECISION array of DIMENSION ( LDB, n ).
*           Before entry,  the leading  m by n part of the array  B must
*           contain  the  right-hand  side  matrix  B,  and  on exit  is
*           overwritten by the solution matrix  X.
*
*  LDB    - INTEGER.
*           On entry, LDB specifies the first dimension of B as declared
*           in  the  calling  (sub)  program.   LDB  must  be  at  least
*           max( 1, m ).
*           Unchanged on exit.
*
*
*  Level 3 Blas routine.
*
*
*  -- Written on 8-February-1989.
*     Jack Dongarra, Argonne National Laboratory.
*     Iain Duff, AERE Harwell.
*     Jeremy Du Croz, Numerical Algorithms Group Ltd.
*     Sven Hammarling, Numerical Algorithms Group Ltd.
*
*
*     .. External Functions ..
      LOGICAL            LSAME
      EXTERNAL           LSAME
*     .. External Subroutines ..
      EXTERNAL           XERBLA
*     .. Intrinsic Functions ..
      INTRINSIC          MAX
*     .. Local Scalars ..
      LOGICAL            LSIDE, NOUNIT, UPPER
      INTEGER            I, INFO, J, K, NROWA
      DOUBLE PRECISION   TEMP
*     .. Parameters ..
      DOUBLE PRECISION   ONE         , ZERO
      PARAMETER        ( ONE = 1.0D+0, ZERO = 0.0D+0 )
*     ..
*     .. Executable Statements ..
*
*     Test the input parameters.
*
      LSIDE  = LSAME( SIDE  , 'L' )
      IF( LSIDE )THEN
     NROWA = M
      ELSE
     NROWA = N
      END IF
      NOUNIT = LSAME( DIAG  , 'N' )
      UPPER  = LSAME( UPLO  , 'U' )
*
      INFO   = 0
      IF(      ( .NOT.LSIDE                ).AND.
     $         ( .NOT.LSAME( SIDE  , 'R' ) )      )THEN
     INFO = 1
      ELSE IF( ( .NOT.UPPER                ).AND.
     $         ( .NOT.LSAME( UPLO  , 'L' ) )      )THEN
     INFO = 2
      ELSE IF( ( .NOT.LSAME( TRANSA, 'N' ) ).AND.
     $         ( .NOT.LSAME( TRANSA, 'T' ) ).AND.
     $         ( .NOT.LSAME( TRANSA, 'C' ) )      )THEN
     INFO = 3
      ELSE IF( ( .NOT.LSAME( DIAG  , 'U' ) ).AND.
     $         ( .NOT.LSAME( DIAG  , 'N' ) )      )THEN
     INFO = 4
      ELSE IF( M  .LT.0               )THEN
     INFO = 5
      ELSE IF( N  .LT.0               )THEN
     INFO = 6
      ELSE IF( LDA.LT.MAX( 1, NROWA ) )THEN
     INFO = 9
      ELSE IF( LDB.LT.MAX( 1, M     ) )THEN
     INFO = 11
      END IF
      IF( INFO.NE.0 )THEN
     CALL XERBLA( 'DTRSM ', INFO )
     RETURN
      END IF
*
*     Quick return if possible.
*
      IF( N.EQ.0 )
     $   RETURN
*
*     And when  alpha.eq.zero.
*
      IF( ALPHA.EQ.ZERO )THEN
     DO 20, J = 1, N
        DO 10, I = 1, M
           B( I, J ) = ZERO
   10       CONTINUE
   20    CONTINUE
     RETURN
      END IF
*
*     Start the operations.
*
      IF( LSIDE )THEN
     IF( LSAME( TRANSA, 'N' ) )THEN
*
*           Form  B := alpha*inv( A )*B.
*
        IF( UPPER )THEN
           DO 60, J = 1, N
          IF( ALPHA.NE.ONE )THEN
             DO 30, I = 1, M
            B( I, J ) = ALPHA*B( I, J )
   30                CONTINUE
          END IF
          DO 50, K = M, 1, -1
             IF( B( K, J ).NE.ZERO )THEN
            IF( NOUNIT )
     $                     B( K, J ) = B( K, J )/A( K, K )
            DO 40, I = 1, K - 1
               B( I, J ) = B( I, J ) - B( K, J )*A( I, K )
   40                   CONTINUE
             END IF
   50             CONTINUE
   60          CONTINUE
        ELSE
           DO 100, J = 1, N
          IF( ALPHA.NE.ONE )THEN
             DO 70, I = 1, M
            B( I, J ) = ALPHA*B( I, J )
   70                CONTINUE
          END IF
          DO 90 K = 1, M
             IF( B( K, J ).NE.ZERO )THEN
            IF( NOUNIT )
     $                     B( K, J ) = B( K, J )/A( K, K )
            DO 80, I = K + 1, M
               B( I, J ) = B( I, J ) - B( K, J )*A( I, K )
   80                   CONTINUE
             END IF
   90             CONTINUE
  100          CONTINUE
        END IF
     ELSE
*
*           Form  B := alpha*inv( A' )*B.
*
        IF( UPPER )THEN
           DO 130, J = 1, N
          DO 120, I = 1, M
             TEMP = ALPHA*B( I, J )
             DO 110, K = 1, I - 1
            TEMP = TEMP - A( K, I )*B( K, J )
  110                CONTINUE
             IF( NOUNIT )
     $                  TEMP = TEMP/A( I, I )
             B( I, J ) = TEMP
  120             CONTINUE
  130          CONTINUE
        ELSE
           DO 160, J = 1, N
          DO 150, I = M, 1, -1
             TEMP = ALPHA*B( I, J )
             DO 140, K = I + 1, M
            TEMP = TEMP - A( K, I )*B( K, J )
  140                CONTINUE
             IF( NOUNIT )
     $                  TEMP = TEMP/A( I, I )
             B( I, J ) = TEMP
  150             CONTINUE
  160          CONTINUE
        END IF
     END IF
      ELSE
     IF( LSAME( TRANSA, 'N' ) )THEN
*
*           Form  B := alpha*B*inv( A ).
*
        IF( UPPER )THEN
           DO 210, J = 1, N
          IF( ALPHA.NE.ONE )THEN
             DO 170, I = 1, M
            B( I, J ) = ALPHA*B( I, J )
  170                CONTINUE
          END IF
          DO 190, K = 1, J - 1
             IF( A( K, J ).NE.ZERO )THEN
            DO 180, I = 1, M
               B( I, J ) = B( I, J ) - A( K, J )*B( I, K )
  180                   CONTINUE
             END IF
  190             CONTINUE
          IF( NOUNIT )THEN
             TEMP = ONE/A( J, J )
             DO 200, I = 1, M
            B( I, J ) = TEMP*B( I, J )
  200                CONTINUE
          END IF
  210          CONTINUE
        ELSE
           DO 260, J = N, 1, -1
          IF( ALPHA.NE.ONE )THEN
             DO 220, I = 1, M
            B( I, J ) = ALPHA*B( I, J )
  220                CONTINUE
          END IF
          DO 240, K = J + 1, N
             IF( A( K, J ).NE.ZERO )THEN
            DO 230, I = 1, M
               B( I, J ) = B( I, J ) - A( K, J )*B( I, K )
  230                   CONTINUE
             END IF
  240             CONTINUE
          IF( NOUNIT )THEN
             TEMP = ONE/A( J, J )
             DO 250, I = 1, M
               B( I, J ) = TEMP*B( I, J )
  250                CONTINUE
          END IF
  260          CONTINUE
        END IF
     ELSE
*
*           Form  B := alpha*B*inv( A' ).
*
        IF( UPPER )THEN
           DO 310, K = N, 1, -1
          IF( NOUNIT )THEN
             TEMP = ONE/A( K, K )
             DO 270, I = 1, M
            B( I, K ) = TEMP*B( I, K )
  270                CONTINUE
          END IF
          DO 290, J = 1, K - 1
             IF( A( J, K ).NE.ZERO )THEN
            TEMP = A( J, K )
            DO 280, I = 1, M
               B( I, J ) = B( I, J ) - TEMP*B( I, K )
  280                   CONTINUE
             END IF
  290             CONTINUE
          IF( ALPHA.NE.ONE )THEN
             DO 300, I = 1, M
            B( I, K ) = ALPHA*B( I, K )
  300                CONTINUE
          END IF
  310          CONTINUE
        ELSE
           DO 360, K = 1, N
          IF( NOUNIT )THEN
             TEMP = ONE/A( K, K )
             DO 320, I = 1, M
            B( I, K ) = TEMP*B( I, K )
  320                CONTINUE
          END IF
          DO 340, J = K + 1, N
             IF( A( J, K ).NE.ZERO )THEN
            TEMP = A( J, K )
            DO 330, I = 1, M
               B( I, J ) = B( I, J ) - TEMP*B( I, K )
  330                   CONTINUE
             END IF
  340             CONTINUE
          IF( ALPHA.NE.ONE )THEN
             DO 350, I = 1, M
            B( I, K ) = ALPHA*B( I, K )
  350                CONTINUE
          END IF
  360          CONTINUE
        END IF
     END IF
      END IF
*
      RETURN
*
*     End of DTRSM .
*
      END
1	SUBROUTINE DTRSM ( SIDE, UPLO, TRANSA, DIAG, M, N, ALPHA, A, LDA,
2	*
3	************************************************************************
4	*
5	$ B, LDB )
6	* .. Scalar Arguments ..
7	CHARACTER*1 SIDE, UPLO, TRANSA, DIAG
8	INTEGER M, N, LDA, LDB
9	DOUBLE PRECISION ALPHA
10	* .. Array Arguments ..
11	DOUBLE PRECISION A( LDA, * ), B( LDB, * )
12	* ..
13	*
14	* Purpose
15	* =======
16	*
17	* DTRSM solves one of the matrix equations
18	*
19	* op( A )X = alphaB, or Xop( A ) = alphaB,
20	*
21	* where alpha is a scalar, X and B are m by n matrices, A is a unit, or
22	* non-unit, upper or lower triangular matrix and op( A ) is one of
23	*
24	* op( A ) = A or op( A ) = A'.
25	*
26	* The matrix X is overwritten on B.
27	*
28	* Parameters
29	* ==========
30	*
31	* SIDE - CHARACTER*1.
32	* On entry, SIDE specifies whether op( A ) appears on the left
33	* or right of X as follows:
34	*
35	* SIDE = 'L' or 'l' op( A )X = alphaB.
36	*
37	* SIDE = 'R' or 'r' Xop( A ) = alphaB.
38	*
39	* Unchanged on exit.
40	*
41	* UPLO - CHARACTER*1.
42	* On entry, UPLO specifies whether the matrix A is an upper or
43	* lower triangular matrix as follows:
44	*
45	* UPLO = 'U' or 'u' A is an upper triangular matrix.
46	*
47	* UPLO = 'L' or 'l' A is a lower triangular matrix.
48	*
49	* Unchanged on exit.
50	*
51	* TRANSA - CHARACTER*1.
52	* On entry, TRANSA specifies the form of op( A ) to be used in
53	* the matrix multiplication as follows:
54	*
55	* TRANSA = 'N' or 'n' op( A ) = A.
56	*
57	* TRANSA = 'T' or 't' op( A ) = A'.
58	*
59	* TRANSA = 'C' or 'c' op( A ) = A'.
60	*
61	* Unchanged on exit.
62	*
63	* DIAG - CHARACTER*1.
64	* On entry, DIAG specifies whether or not A is unit triangular
65	* as follows:
66	*
67	* DIAG = 'U' or 'u' A is assumed to be unit triangular.
68	*
69	* DIAG = 'N' or 'n' A is not assumed to be unit
70	* triangular.
71	*
72	* Unchanged on exit.
73	*
74	* M - INTEGER.
75	* On entry, M specifies the number of rows of B. M must be at
76	* least zero.
77	* Unchanged on exit.
78	*
79	* N - INTEGER.
80	* On entry, N specifies the number of columns of B. N must be
81	* at least zero.
82	* Unchanged on exit.
83	*
84	* ALPHA - DOUBLE PRECISION.
85	* On entry, ALPHA specifies the scalar alpha. When alpha is
86	* zero then A is not referenced and B need not be set before
87	* entry.
88	* Unchanged on exit.
89	*
90	* A - DOUBLE PRECISION array of DIMENSION ( LDA, k ), where k is m
91	* when SIDE = 'L' or 'l' and is n when SIDE = 'R' or 'r'.
92	* Before entry with UPLO = 'U' or 'u', the leading k by k
93	* upper triangular part of the array A must contain the upper
94	* triangular matrix and the strictly lower triangular part of
95	* A is not referenced.
96	* Before entry with UPLO = 'L' or 'l', the leading k by k
97	* lower triangular part of the array A must contain the lower
98	* triangular matrix and the strictly upper triangular part of
99	* A is not referenced.
100	* Note that when DIAG = 'U' or 'u', the diagonal elements of
101	* A are not referenced either, but are assumed to be unity.
102	* Unchanged on exit.
103	*
104	* LDA - INTEGER.
105	* On entry, LDA specifies the first dimension of A as declared
106	* in the calling (sub) program. When SIDE = 'L' or 'l' then
107	* LDA must be at least max( 1, m ), when SIDE = 'R' or 'r'
108	* then LDA must be at least max( 1, n ).
109	* Unchanged on exit.
110	*
111	* B - DOUBLE PRECISION array of DIMENSION ( LDB, n ).
112	* Before entry, the leading m by n part of the array B must
113	* contain the right-hand side matrix B, and on exit is
114	* overwritten by the solution matrix X.
115	*
116	* LDB - INTEGER.
117	* On entry, LDB specifies the first dimension of B as declared
118	* in the calling (sub) program. LDB must be at least
119	* max( 1, m ).
120	* Unchanged on exit.
121	*
122	*
123	* Level 3 Blas routine.
124	*
125	*
126	* -- Written on 8-February-1989.
127	* Jack Dongarra, Argonne National Laboratory.
128	* Iain Duff, AERE Harwell.
129	* Jeremy Du Croz, Numerical Algorithms Group Ltd.
130	* Sven Hammarling, Numerical Algorithms Group Ltd.
131	*
132	*
133	* .. External Functions ..
134	LOGICAL LSAME
135	EXTERNAL LSAME
136	* .. External Subroutines ..
137	EXTERNAL XERBLA
138	* .. Intrinsic Functions ..
139	INTRINSIC MAX
140	* .. Local Scalars ..
141	LOGICAL LSIDE, NOUNIT, UPPER
142	INTEGER I, INFO, J, K, NROWA
143	DOUBLE PRECISION TEMP
144	* .. Parameters ..
145	DOUBLE PRECISION ONE , ZERO
146	PARAMETER ( ONE = 1.0D+0, ZERO = 0.0D+0 )
147	* ..
148	* .. Executable Statements ..
149	*
150	* Test the input parameters.
151	*
152	LSIDE = LSAME( SIDE , 'L' )
153	IF( LSIDE )THEN
154	NROWA = M
155	ELSE
156	NROWA = N
157	END IF
158	NOUNIT = LSAME( DIAG , 'N' )
159	UPPER = LSAME( UPLO , 'U' )
160	*
161	INFO = 0
162	IF( ( .NOT.LSIDE ).AND.
163	$ ( .NOT.LSAME( SIDE , 'R' ) ) )THEN
164	INFO = 1
165	ELSE IF( ( .NOT.UPPER ).AND.
166	$ ( .NOT.LSAME( UPLO , 'L' ) ) )THEN
167	INFO = 2
168	ELSE IF( ( .NOT.LSAME( TRANSA, 'N' ) ).AND.
169	$ ( .NOT.LSAME( TRANSA, 'T' ) ).AND.
170	$ ( .NOT.LSAME( TRANSA, 'C' ) ) )THEN
171	INFO = 3
172	ELSE IF( ( .NOT.LSAME( DIAG , 'U' ) ).AND.
173	$ ( .NOT.LSAME( DIAG , 'N' ) ) )THEN
174	INFO = 4
175	ELSE IF( M .LT.0 )THEN
176	INFO = 5
177	ELSE IF( N .LT.0 )THEN
178	INFO = 6
179	ELSE IF( LDA.LT.MAX( 1, NROWA ) )THEN
180	INFO = 9
181	ELSE IF( LDB.LT.MAX( 1, M ) )THEN
182	INFO = 11
183	END IF
184	IF( INFO.NE.0 )THEN
185	CALL XERBLA( 'DTRSM ', INFO )
186	RETURN
187	END IF
188	*
189	* Quick return if possible.
190	*
191	IF( N.EQ.0 )
192	$ RETURN
193	*
194	* And when alpha.eq.zero.
195	*
196	IF( ALPHA.EQ.ZERO )THEN
197	DO 20, J = 1, N
198	DO 10, I = 1, M
199	B( I, J ) = ZERO
200	10 CONTINUE
201	20 CONTINUE
202	RETURN
203	END IF
204	*
205	* Start the operations.
206	*
207	IF( LSIDE )THEN
208	IF( LSAME( TRANSA, 'N' ) )THEN
209	*
210	* Form B := alphainv( A )B.
211	*
212	IF( UPPER )THEN
213	DO 60, J = 1, N
214	IF( ALPHA.NE.ONE )THEN
215	DO 30, I = 1, M
216	B( I, J ) = ALPHA*B( I, J )
217	30 CONTINUE
218	END IF
219	DO 50, K = M, 1, -1
220	IF( B( K, J ).NE.ZERO )THEN
221	IF( NOUNIT )
222	$ B( K, J ) = B( K, J )/A( K, K )
223	DO 40, I = 1, K - 1
224	B( I, J ) = B( I, J ) - B( K, J )*A( I, K )
225	40 CONTINUE
226	END IF
227	50 CONTINUE
228	60 CONTINUE
229	ELSE
230	DO 100, J = 1, N
231	IF( ALPHA.NE.ONE )THEN
232	DO 70, I = 1, M
233	B( I, J ) = ALPHA*B( I, J )
234	70 CONTINUE
235	END IF
236	DO 90 K = 1, M
237	IF( B( K, J ).NE.ZERO )THEN
238	IF( NOUNIT )
239	$ B( K, J ) = B( K, J )/A( K, K )
240	DO 80, I = K + 1, M
241	B( I, J ) = B( I, J ) - B( K, J )*A( I, K )
242	80 CONTINUE
243	END IF
244	90 CONTINUE
245	100 CONTINUE
246	END IF
247	ELSE
248	*
249	* Form B := alphainv( A' )B.
250	*
251	IF( UPPER )THEN
252	DO 130, J = 1, N
253	DO 120, I = 1, M
254	TEMP = ALPHA*B( I, J )
255	DO 110, K = 1, I - 1
256	TEMP = TEMP - A( K, I )*B( K, J )
257	110 CONTINUE
258	IF( NOUNIT )
259	$ TEMP = TEMP/A( I, I )
260	B( I, J ) = TEMP
261	120 CONTINUE
262	130 CONTINUE
263	ELSE
264	DO 160, J = 1, N
265	DO 150, I = M, 1, -1
266	TEMP = ALPHA*B( I, J )
267	DO 140, K = I + 1, M
268	TEMP = TEMP - A( K, I )*B( K, J )
269	140 CONTINUE
270	IF( NOUNIT )
271	$ TEMP = TEMP/A( I, I )
272	B( I, J ) = TEMP
273	150 CONTINUE
274	160 CONTINUE
275	END IF
276	END IF
277	ELSE
278	IF( LSAME( TRANSA, 'N' ) )THEN
279	*
280	* Form B := alphaBinv( A ).
281	*
282	IF( UPPER )THEN
283	DO 210, J = 1, N
284	IF( ALPHA.NE.ONE )THEN
285	DO 170, I = 1, M
286	B( I, J ) = ALPHA*B( I, J )
287	170 CONTINUE
288	END IF
289	DO 190, K = 1, J - 1
290	IF( A( K, J ).NE.ZERO )THEN
291	DO 180, I = 1, M
292	B( I, J ) = B( I, J ) - A( K, J )*B( I, K )
293	180 CONTINUE
294	END IF
295	190 CONTINUE
296	IF( NOUNIT )THEN
297	TEMP = ONE/A( J, J )
298	DO 200, I = 1, M
299	B( I, J ) = TEMP*B( I, J )
300	200 CONTINUE
301	END IF
302	210 CONTINUE
303	ELSE
304	DO 260, J = N, 1, -1
305	IF( ALPHA.NE.ONE )THEN
306	DO 220, I = 1, M
307	B( I, J ) = ALPHA*B( I, J )
308	220 CONTINUE
309	END IF
310	DO 240, K = J + 1, N
311	IF( A( K, J ).NE.ZERO )THEN
312	DO 230, I = 1, M
313	B( I, J ) = B( I, J ) - A( K, J )*B( I, K )
314	230 CONTINUE
315	END IF
316	240 CONTINUE
317	IF( NOUNIT )THEN
318	TEMP = ONE/A( J, J )
319	DO 250, I = 1, M
320	B( I, J ) = TEMP*B( I, J )
321	250 CONTINUE
322	END IF
323	260 CONTINUE
324	END IF
325	ELSE
326	*
327	* Form B := alphaBinv( A' ).
328	*
329	IF( UPPER )THEN
330	DO 310, K = N, 1, -1
331	IF( NOUNIT )THEN
332	TEMP = ONE/A( K, K )
333	DO 270, I = 1, M
334	B( I, K ) = TEMP*B( I, K )
335	270 CONTINUE
336	END IF
337	DO 290, J = 1, K - 1
338	IF( A( J, K ).NE.ZERO )THEN
339	TEMP = A( J, K )
340	DO 280, I = 1, M
341	B( I, J ) = B( I, J ) - TEMP*B( I, K )
342	280 CONTINUE
343	END IF
344	290 CONTINUE
345	IF( ALPHA.NE.ONE )THEN
346	DO 300, I = 1, M
347	B( I, K ) = ALPHA*B( I, K )
348	300 CONTINUE
349	END IF
350	310 CONTINUE
351	ELSE
352	DO 360, K = 1, N
353	IF( NOUNIT )THEN
354	TEMP = ONE/A( K, K )
355	DO 320, I = 1, M
356	B( I, K ) = TEMP*B( I, K )
357	320 CONTINUE
358	END IF
359	DO 340, J = K + 1, N
360	IF( A( J, K ).NE.ZERO )THEN
361	TEMP = A( J, K )
362	DO 330, I = 1, M
363	B( I, J ) = B( I, J ) - TEMP*B( I, K )
364	330 CONTINUE
365	END IF
366	340 CONTINUE
367	IF( ALPHA.NE.ONE )THEN
368	DO 350, I = 1, M
369	B( I, K ) = ALPHA*B( I, K )
370	350 CONTINUE
371	END IF
372	360 CONTINUE
373	END IF
374	END IF
375	END IF
376	*
377	RETURN
378	*
379	* End of DTRSM .
380	*
381	END