SUBROUTINE CTRSM(SIDE,UPLO,TRANSA,DIAG,M,N,ALPHA,A,LDA,B,LDB)
COMPLEX ALPHA
INTEGER LDA,LDB,M,N
CHARACTER DIAG,SIDE,TRANSA,UPLO
COMPLEX A(LDA,*),B(LDB,*)
LOGICAL LSAME
EXTERNAL LSAME
EXTERNAL XERBLA
INTRINSIC CONJG,MAX
COMPLEX TEMP
INTEGER I,INFO,J,K,NROWA
LOGICAL LSIDE,NOCONJ,NOUNIT,UPPER
COMPLEX ONE
PARAMETER (ONE= (1.0E+0,0.0E+0))
COMPLEX ZERO
PARAMETER (ZERO= (0.0E+0,0.0E+0))
LSIDE = LSAME(SIDE,'L')
IF (LSIDE) THEN
NROWA = M
ELSE
NROWA = N
END IF
NOCONJ = LSAME(TRANSA,'T')
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('CTRSM ',INFO)
RETURN
END IF
IF (N.EQ.0) RETURN
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
IF (LSIDE) THEN
IF (LSAME(TRANSA,'N')) THEN
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
IF (UPPER) THEN
DO 140 J = 1,N
DO 130 I = 1,M
TEMP = ALPHA*B(I,J)
IF (NOCONJ) THEN
DO 110 K = 1,I - 1
TEMP = TEMP - A(K,I)*B(K,J)
110 CONTINUE
IF (NOUNIT) TEMP = TEMP/A(I,I)
ELSE
DO 120 K = 1,I - 1
TEMP = TEMP - CONJG(A(K,I))*B(K,J)
120 CONTINUE
IF (NOUNIT) TEMP = TEMP/CONJG(A(I,I))
END IF
B(I,J) = TEMP
130 CONTINUE
140 CONTINUE
ELSE
DO 180 J = 1,N
DO 170 I = M,1,-1
TEMP = ALPHA*B(I,J)
IF (NOCONJ) THEN
DO 150 K = I + 1,M
TEMP = TEMP - A(K,I)*B(K,J)
150 CONTINUE
IF (NOUNIT) TEMP = TEMP/A(I,I)
ELSE
DO 160 K = I + 1,M
TEMP = TEMP - CONJG(A(K,I))*B(K,J)
160 CONTINUE
IF (NOUNIT) TEMP = TEMP/CONJG(A(I,I))
END IF
B(I,J) = TEMP
170 CONTINUE
180 CONTINUE
END IF
END IF
ELSE
IF (LSAME(TRANSA,'N')) THEN
IF (UPPER) THEN
DO 230 J = 1,N
IF (ALPHA.NE.ONE) THEN
DO 190 I = 1,M
B(I,J) = ALPHA*B(I,J)
190 CONTINUE
END IF
DO 210 K = 1,J - 1
IF (A(K,J).NE.ZERO) THEN
DO 200 I = 1,M
B(I,J) = B(I,J) - A(K,J)*B(I,K)
200 CONTINUE
END IF
210 CONTINUE
IF (NOUNIT) THEN
TEMP = ONE/A(J,J)
DO 220 I = 1,M
B(I,J) = TEMP*B(I,J)
220 CONTINUE
END IF
230 CONTINUE
ELSE
DO 280 J = N,1,-1
IF (ALPHA.NE.ONE) THEN
DO 240 I = 1,M
B(I,J) = ALPHA*B(I,J)
240 CONTINUE
END IF
DO 260 K = J + 1,N
IF (A(K,J).NE.ZERO) THEN
DO 250 I = 1,M
B(I,J) = B(I,J) - A(K,J)*B(I,K)
250 CONTINUE
END IF
260 CONTINUE
IF (NOUNIT) THEN
TEMP = ONE/A(J,J)
DO 270 I = 1,M
B(I,J) = TEMP*B(I,J)
270 CONTINUE
END IF
280 CONTINUE
END IF
ELSE
IF (UPPER) THEN
DO 330 K = N,1,-1
IF (NOUNIT) THEN
IF (NOCONJ) THEN
TEMP = ONE/A(K,K)
ELSE
TEMP = ONE/CONJG(A(K,K))
END IF
DO 290 I = 1,M
B(I,K) = TEMP*B(I,K)
290 CONTINUE
END IF
DO 310 J = 1,K - 1
IF (A(J,K).NE.ZERO) THEN
IF (NOCONJ) THEN
TEMP = A(J,K)
ELSE
TEMP = CONJG(A(J,K))
END IF
DO 300 I = 1,M
B(I,J) = B(I,J) - TEMP*B(I,K)
300 CONTINUE
END IF
310 CONTINUE
IF (ALPHA.NE.ONE) THEN
DO 320 I = 1,M
B(I,K) = ALPHA*B(I,K)
320 CONTINUE
END IF
330 CONTINUE
ELSE
DO 380 K = 1,N
IF (NOUNIT) THEN
IF (NOCONJ) THEN
TEMP = ONE/A(K,K)
ELSE
TEMP = ONE/CONJG(A(K,K))
END IF
DO 340 I = 1,M
B(I,K) = TEMP*B(I,K)
340 CONTINUE
END IF
DO 360 J = K + 1,N
IF (A(J,K).NE.ZERO) THEN
IF (NOCONJ) THEN
TEMP = A(J,K)
ELSE
TEMP = CONJG(A(J,K))
END IF
DO 350 I = 1,M
B(I,J) = B(I,J) - TEMP*B(I,K)
350 CONTINUE
END IF
360 CONTINUE
IF (ALPHA.NE.ONE) THEN
DO 370 I = 1,M
B(I,K) = ALPHA*B(I,K)
370 CONTINUE
END IF
380 CONTINUE
END IF
END IF
END IF
RETURN
END