1 SUBROUTINE CTBMV(UPLO,TRANS,DIAG,N,K,A,LDA,X,INCX)
2 * .. Scalar Arguments ..
3 INTEGER INCX,K,LDA,N
4 CHARACTER DIAG,TRANS,UPLO
5 * ..
6 * .. Array Arguments ..
7 COMPLEX A(LDA,*),X(*)
8 * ..
9 *
10 * Purpose
11 * =======
12 *
13 * CTBMV performs one of the matrix-vector operations
14 *
15 * x := A*x, or x := A**T*x, or x := A**H*x,
16 *
17 * where x is an n element vector and A is an n by n unit, or non-unit,
18 * upper or lower triangular band matrix, with ( k + 1 ) diagonals.
19 *
20 * Arguments
21 * ==========
22 *
23 * UPLO - CHARACTER*1.
24 * On entry, UPLO specifies whether the matrix is an upper or
25 * lower triangular matrix as follows:
26 *
27 * UPLO = 'U' or 'u' A is an upper triangular matrix.
28 *
29 * UPLO = 'L' or 'l' A is a lower triangular matrix.
30 *
31 * Unchanged on exit.
32 *
33 * TRANS - CHARACTER*1.
34 * On entry, TRANS specifies the operation to be performed as
35 * follows:
36 *
37 * TRANS = 'N' or 'n' x := A*x.
38 *
39 * TRANS = 'T' or 't' x := A**T*x.
40 *
41 * TRANS = 'C' or 'c' x := A**H*x.
42 *
43 * Unchanged on exit.
44 *
45 * DIAG - CHARACTER*1.
46 * On entry, DIAG specifies whether or not A is unit
47 * triangular as follows:
48 *
49 * DIAG = 'U' or 'u' A is assumed to be unit triangular.
50 *
51 * DIAG = 'N' or 'n' A is not assumed to be unit
52 * triangular.
53 *
54 * Unchanged on exit.
55 *
56 * N - INTEGER.
57 * On entry, N specifies the order of the matrix A.
58 * N must be at least zero.
59 * Unchanged on exit.
60 *
61 * K - INTEGER.
62 * On entry with UPLO = 'U' or 'u', K specifies the number of
63 * super-diagonals of the matrix A.
64 * On entry with UPLO = 'L' or 'l', K specifies the number of
65 * sub-diagonals of the matrix A.
66 * K must satisfy 0 .le. K.
67 * Unchanged on exit.
68 *
69 * A - COMPLEX array of DIMENSION ( LDA, n ).
70 * Before entry with UPLO = 'U' or 'u', the leading ( k + 1 )
71 * by n part of the array A must contain the upper triangular
72 * band part of the matrix of coefficients, supplied column by
73 * column, with the leading diagonal of the matrix in row
74 * ( k + 1 ) of the array, the first super-diagonal starting at
75 * position 2 in row k, and so on. The top left k by k triangle
76 * of the array A is not referenced.
77 * The following program segment will transfer an upper
78 * triangular band matrix from conventional full matrix storage
79 * to band storage:
80 *
81 * DO 20, J = 1, N
82 * M = K + 1 - J
83 * DO 10, I = MAX( 1, J - K ), J
84 * A( M + I, J ) = matrix( I, J )
85 * 10 CONTINUE
86 * 20 CONTINUE
87 *
88 * Before entry with UPLO = 'L' or 'l', the leading ( k + 1 )
89 * by n part of the array A must contain the lower triangular
90 * band part of the matrix of coefficients, supplied column by
91 * column, with the leading diagonal of the matrix in row 1 of
92 * the array, the first sub-diagonal starting at position 1 in
93 * row 2, and so on. The bottom right k by k triangle of the
94 * array A is not referenced.
95 * The following program segment will transfer a lower
96 * triangular band matrix from conventional full matrix storage
97 * to band storage:
98 *
99 * DO 20, J = 1, N
100 * M = 1 - J
101 * DO 10, I = J, MIN( N, J + K )
102 * A( M + I, J ) = matrix( I, J )
103 * 10 CONTINUE
104 * 20 CONTINUE
105 *
106 * Note that when DIAG = 'U' or 'u' the elements of the array A
107 * corresponding to the diagonal elements of the matrix are not
108 * referenced, but are assumed to be unity.
109 * Unchanged on exit.
110 *
111 * LDA - INTEGER.
112 * On entry, LDA specifies the first dimension of A as declared
113 * in the calling (sub) program. LDA must be at least
114 * ( k + 1 ).
115 * Unchanged on exit.
116 *
117 * X - COMPLEX array of dimension at least
118 * ( 1 + ( n - 1 )*abs( INCX ) ).
119 * Before entry, the incremented array X must contain the n
120 * element vector x. On exit, X is overwritten with the
121 * tranformed vector x.
122 *
123 * INCX - INTEGER.
124 * On entry, INCX specifies the increment for the elements of
125 * X. INCX must not be zero.
126 * Unchanged on exit.
127 *
128 * Further Details
129 * ===============
130 *
131 * Level 2 Blas routine.
132 * The vector and matrix arguments are not referenced when N = 0, or M = 0
133 *
134 * -- Written on 22-October-1986.
135 * Jack Dongarra, Argonne National Lab.
136 * Jeremy Du Croz, Nag Central Office.
137 * Sven Hammarling, Nag Central Office.
138 * Richard Hanson, Sandia National Labs.
139 *
140 * =====================================================================
141 *
142 * .. Parameters ..
143 COMPLEX ZERO
144 PARAMETER (ZERO= (0.0E+0,0.0E+0))
145 * ..
146 * .. Local Scalars ..
147 COMPLEX TEMP
148 INTEGER I,INFO,IX,J,JX,KPLUS1,KX,L
149 LOGICAL NOCONJ,NOUNIT
150 * ..
151 * .. External Functions ..
152 LOGICAL LSAME
153 EXTERNAL LSAME
154 * ..
155 * .. External Subroutines ..
156 EXTERNAL XERBLA
157 * ..
158 * .. Intrinsic Functions ..
159 INTRINSIC CONJG,MAX,MIN
160 * ..
161 *
162 * Test the input parameters.
163 *
164 INFO = 0
165 IF (.NOT.LSAME(UPLO,'U') .AND. .NOT.LSAME(UPLO,'L')) THEN
166 INFO = 1
167 ELSE IF (.NOT.LSAME(TRANS,'N') .AND. .NOT.LSAME(TRANS,'T') .AND.
168 + .NOT.LSAME(TRANS,'C')) THEN
169 INFO = 2
170 ELSE IF (.NOT.LSAME(DIAG,'U') .AND. .NOT.LSAME(DIAG,'N')) THEN
171 INFO = 3
172 ELSE IF (N.LT.0) THEN
173 INFO = 4
174 ELSE IF (K.LT.0) THEN
175 INFO = 5
176 ELSE IF (LDA.LT. (K+1)) THEN
177 INFO = 7
178 ELSE IF (INCX.EQ.0) THEN
179 INFO = 9
180 END IF
181 IF (INFO.NE.0) THEN
182 CALL XERBLA('CTBMV ',INFO)
183 RETURN
184 END IF
185 *
186 * Quick return if possible.
187 *
188 IF (N.EQ.0) RETURN
189 *
190 NOCONJ = LSAME(TRANS,'T')
191 NOUNIT = LSAME(DIAG,'N')
192 *
193 * Set up the start point in X if the increment is not unity. This
194 * will be ( N - 1 )*INCX too small for descending loops.
195 *
196 IF (INCX.LE.0) THEN
197 KX = 1 - (N-1)*INCX
198 ELSE IF (INCX.NE.1) THEN
199 KX = 1
200 END IF
201 *
202 * Start the operations. In this version the elements of A are
203 * accessed sequentially with one pass through A.
204 *
205 IF (LSAME(TRANS,'N')) THEN
206 *
207 * Form x := A*x.
208 *
209 IF (LSAME(UPLO,'U')) THEN
210 KPLUS1 = K + 1
211 IF (INCX.EQ.1) THEN
212 DO 20 J = 1,N
213 IF (X(J).NE.ZERO) THEN
214 TEMP = X(J)
215 L = KPLUS1 - J
216 DO 10 I = MAX(1,J-K),J - 1
217 X(I) = X(I) + TEMP*A(L+I,J)
218 10 CONTINUE
219 IF (NOUNIT) X(J) = X(J)*A(KPLUS1,J)
220 END IF
221 20 CONTINUE
222 ELSE
223 JX = KX
224 DO 40 J = 1,N
225 IF (X(JX).NE.ZERO) THEN
226 TEMP = X(JX)
227 IX = KX
228 L = KPLUS1 - J
229 DO 30 I = MAX(1,J-K),J - 1
230 X(IX) = X(IX) + TEMP*A(L+I,J)
231 IX = IX + INCX
232 30 CONTINUE
233 IF (NOUNIT) X(JX) = X(JX)*A(KPLUS1,J)
234 END IF
235 JX = JX + INCX
236 IF (J.GT.K) KX = KX + INCX
237 40 CONTINUE
238 END IF
239 ELSE
240 IF (INCX.EQ.1) THEN
241 DO 60 J = N,1,-1
242 IF (X(J).NE.ZERO) THEN
243 TEMP = X(J)
244 L = 1 - J
245 DO 50 I = MIN(N,J+K),J + 1,-1
246 X(I) = X(I) + TEMP*A(L+I,J)
247 50 CONTINUE
248 IF (NOUNIT) X(J) = X(J)*A(1,J)
249 END IF
250 60 CONTINUE
251 ELSE
252 KX = KX + (N-1)*INCX
253 JX = KX
254 DO 80 J = N,1,-1
255 IF (X(JX).NE.ZERO) THEN
256 TEMP = X(JX)
257 IX = KX
258 L = 1 - J
259 DO 70 I = MIN(N,J+K),J + 1,-1
260 X(IX) = X(IX) + TEMP*A(L+I,J)
261 IX = IX - INCX
262 70 CONTINUE
263 IF (NOUNIT) X(JX) = X(JX)*A(1,J)
264 END IF
265 JX = JX - INCX
266 IF ((N-J).GE.K) KX = KX - INCX
267 80 CONTINUE
268 END IF
269 END IF
270 ELSE
271 *
272 * Form x := A**T*x or x := A**H*x.
273 *
274 IF (LSAME(UPLO,'U')) THEN
275 KPLUS1 = K + 1
276 IF (INCX.EQ.1) THEN
277 DO 110 J = N,1,-1
278 TEMP = X(J)
279 L = KPLUS1 - J
280 IF (NOCONJ) THEN
281 IF (NOUNIT) TEMP = TEMP*A(KPLUS1,J)
282 DO 90 I = J - 1,MAX(1,J-K),-1
283 TEMP = TEMP + A(L+I,J)*X(I)
284 90 CONTINUE
285 ELSE
286 IF (NOUNIT) TEMP = TEMP*CONJG(A(KPLUS1,J))
287 DO 100 I = J - 1,MAX(1,J-K),-1
288 TEMP = TEMP + CONJG(A(L+I,J))*X(I)
289 100 CONTINUE
290 END IF
291 X(J) = TEMP
292 110 CONTINUE
293 ELSE
294 KX = KX + (N-1)*INCX
295 JX = KX
296 DO 140 J = N,1,-1
297 TEMP = X(JX)
298 KX = KX - INCX
299 IX = KX
300 L = KPLUS1 - J
301 IF (NOCONJ) THEN
302 IF (NOUNIT) TEMP = TEMP*A(KPLUS1,J)
303 DO 120 I = J - 1,MAX(1,J-K),-1
304 TEMP = TEMP + A(L+I,J)*X(IX)
305 IX = IX - INCX
306 120 CONTINUE
307 ELSE
308 IF (NOUNIT) TEMP = TEMP*CONJG(A(KPLUS1,J))
309 DO 130 I = J - 1,MAX(1,J-K),-1
310 TEMP = TEMP + CONJG(A(L+I,J))*X(IX)
311 IX = IX - INCX
312 130 CONTINUE
313 END IF
314 X(JX) = TEMP
315 JX = JX - INCX
316 140 CONTINUE
317 END IF
318 ELSE
319 IF (INCX.EQ.1) THEN
320 DO 170 J = 1,N
321 TEMP = X(J)
322 L = 1 - J
323 IF (NOCONJ) THEN
324 IF (NOUNIT) TEMP = TEMP*A(1,J)
325 DO 150 I = J + 1,MIN(N,J+K)
326 TEMP = TEMP + A(L+I,J)*X(I)
327 150 CONTINUE
328 ELSE
329 IF (NOUNIT) TEMP = TEMP*CONJG(A(1,J))
330 DO 160 I = J + 1,MIN(N,J+K)
331 TEMP = TEMP + CONJG(A(L+I,J))*X(I)
332 160 CONTINUE
333 END IF
334 X(J) = TEMP
335 170 CONTINUE
336 ELSE
337 JX = KX
338 DO 200 J = 1,N
339 TEMP = X(JX)
340 KX = KX + INCX
341 IX = KX
342 L = 1 - J
343 IF (NOCONJ) THEN
344 IF (NOUNIT) TEMP = TEMP*A(1,J)
345 DO 180 I = J + 1,MIN(N,J+K)
346 TEMP = TEMP + A(L+I,J)*X(IX)
347 IX = IX + INCX
348 180 CONTINUE
349 ELSE
350 IF (NOUNIT) TEMP = TEMP*CONJG(A(1,J))
351 DO 190 I = J + 1,MIN(N,J+K)
352 TEMP = TEMP + CONJG(A(L+I,J))*X(IX)
353 IX = IX + INCX
354 190 CONTINUE
355 END IF
356 X(JX) = TEMP
357 JX = JX + INCX
358 200 CONTINUE
359 END IF
360 END IF
361 END IF
362 *
363 RETURN
364 *
365 * End of CTBMV .
366 *
367 END
2 * .. Scalar Arguments ..
3 INTEGER INCX,K,LDA,N
4 CHARACTER DIAG,TRANS,UPLO
5 * ..
6 * .. Array Arguments ..
7 COMPLEX A(LDA,*),X(*)
8 * ..
9 *
10 * Purpose
11 * =======
12 *
13 * CTBMV performs one of the matrix-vector operations
14 *
15 * x := A*x, or x := A**T*x, or x := A**H*x,
16 *
17 * where x is an n element vector and A is an n by n unit, or non-unit,
18 * upper or lower triangular band matrix, with ( k + 1 ) diagonals.
19 *
20 * Arguments
21 * ==========
22 *
23 * UPLO - CHARACTER*1.
24 * On entry, UPLO specifies whether the matrix is an upper or
25 * lower triangular matrix as follows:
26 *
27 * UPLO = 'U' or 'u' A is an upper triangular matrix.
28 *
29 * UPLO = 'L' or 'l' A is a lower triangular matrix.
30 *
31 * Unchanged on exit.
32 *
33 * TRANS - CHARACTER*1.
34 * On entry, TRANS specifies the operation to be performed as
35 * follows:
36 *
37 * TRANS = 'N' or 'n' x := A*x.
38 *
39 * TRANS = 'T' or 't' x := A**T*x.
40 *
41 * TRANS = 'C' or 'c' x := A**H*x.
42 *
43 * Unchanged on exit.
44 *
45 * DIAG - CHARACTER*1.
46 * On entry, DIAG specifies whether or not A is unit
47 * triangular as follows:
48 *
49 * DIAG = 'U' or 'u' A is assumed to be unit triangular.
50 *
51 * DIAG = 'N' or 'n' A is not assumed to be unit
52 * triangular.
53 *
54 * Unchanged on exit.
55 *
56 * N - INTEGER.
57 * On entry, N specifies the order of the matrix A.
58 * N must be at least zero.
59 * Unchanged on exit.
60 *
61 * K - INTEGER.
62 * On entry with UPLO = 'U' or 'u', K specifies the number of
63 * super-diagonals of the matrix A.
64 * On entry with UPLO = 'L' or 'l', K specifies the number of
65 * sub-diagonals of the matrix A.
66 * K must satisfy 0 .le. K.
67 * Unchanged on exit.
68 *
69 * A - COMPLEX array of DIMENSION ( LDA, n ).
70 * Before entry with UPLO = 'U' or 'u', the leading ( k + 1 )
71 * by n part of the array A must contain the upper triangular
72 * band part of the matrix of coefficients, supplied column by
73 * column, with the leading diagonal of the matrix in row
74 * ( k + 1 ) of the array, the first super-diagonal starting at
75 * position 2 in row k, and so on. The top left k by k triangle
76 * of the array A is not referenced.
77 * The following program segment will transfer an upper
78 * triangular band matrix from conventional full matrix storage
79 * to band storage:
80 *
81 * DO 20, J = 1, N
82 * M = K + 1 - J
83 * DO 10, I = MAX( 1, J - K ), J
84 * A( M + I, J ) = matrix( I, J )
85 * 10 CONTINUE
86 * 20 CONTINUE
87 *
88 * Before entry with UPLO = 'L' or 'l', the leading ( k + 1 )
89 * by n part of the array A must contain the lower triangular
90 * band part of the matrix of coefficients, supplied column by
91 * column, with the leading diagonal of the matrix in row 1 of
92 * the array, the first sub-diagonal starting at position 1 in
93 * row 2, and so on. The bottom right k by k triangle of the
94 * array A is not referenced.
95 * The following program segment will transfer a lower
96 * triangular band matrix from conventional full matrix storage
97 * to band storage:
98 *
99 * DO 20, J = 1, N
100 * M = 1 - J
101 * DO 10, I = J, MIN( N, J + K )
102 * A( M + I, J ) = matrix( I, J )
103 * 10 CONTINUE
104 * 20 CONTINUE
105 *
106 * Note that when DIAG = 'U' or 'u' the elements of the array A
107 * corresponding to the diagonal elements of the matrix are not
108 * referenced, but are assumed to be unity.
109 * Unchanged on exit.
110 *
111 * LDA - INTEGER.
112 * On entry, LDA specifies the first dimension of A as declared
113 * in the calling (sub) program. LDA must be at least
114 * ( k + 1 ).
115 * Unchanged on exit.
116 *
117 * X - COMPLEX array of dimension at least
118 * ( 1 + ( n - 1 )*abs( INCX ) ).
119 * Before entry, the incremented array X must contain the n
120 * element vector x. On exit, X is overwritten with the
121 * tranformed vector x.
122 *
123 * INCX - INTEGER.
124 * On entry, INCX specifies the increment for the elements of
125 * X. INCX must not be zero.
126 * Unchanged on exit.
127 *
128 * Further Details
129 * ===============
130 *
131 * Level 2 Blas routine.
132 * The vector and matrix arguments are not referenced when N = 0, or M = 0
133 *
134 * -- Written on 22-October-1986.
135 * Jack Dongarra, Argonne National Lab.
136 * Jeremy Du Croz, Nag Central Office.
137 * Sven Hammarling, Nag Central Office.
138 * Richard Hanson, Sandia National Labs.
139 *
140 * =====================================================================
141 *
142 * .. Parameters ..
143 COMPLEX ZERO
144 PARAMETER (ZERO= (0.0E+0,0.0E+0))
145 * ..
146 * .. Local Scalars ..
147 COMPLEX TEMP
148 INTEGER I,INFO,IX,J,JX,KPLUS1,KX,L
149 LOGICAL NOCONJ,NOUNIT
150 * ..
151 * .. External Functions ..
152 LOGICAL LSAME
153 EXTERNAL LSAME
154 * ..
155 * .. External Subroutines ..
156 EXTERNAL XERBLA
157 * ..
158 * .. Intrinsic Functions ..
159 INTRINSIC CONJG,MAX,MIN
160 * ..
161 *
162 * Test the input parameters.
163 *
164 INFO = 0
165 IF (.NOT.LSAME(UPLO,'U') .AND. .NOT.LSAME(UPLO,'L')) THEN
166 INFO = 1
167 ELSE IF (.NOT.LSAME(TRANS,'N') .AND. .NOT.LSAME(TRANS,'T') .AND.
168 + .NOT.LSAME(TRANS,'C')) THEN
169 INFO = 2
170 ELSE IF (.NOT.LSAME(DIAG,'U') .AND. .NOT.LSAME(DIAG,'N')) THEN
171 INFO = 3
172 ELSE IF (N.LT.0) THEN
173 INFO = 4
174 ELSE IF (K.LT.0) THEN
175 INFO = 5
176 ELSE IF (LDA.LT. (K+1)) THEN
177 INFO = 7
178 ELSE IF (INCX.EQ.0) THEN
179 INFO = 9
180 END IF
181 IF (INFO.NE.0) THEN
182 CALL XERBLA('CTBMV ',INFO)
183 RETURN
184 END IF
185 *
186 * Quick return if possible.
187 *
188 IF (N.EQ.0) RETURN
189 *
190 NOCONJ = LSAME(TRANS,'T')
191 NOUNIT = LSAME(DIAG,'N')
192 *
193 * Set up the start point in X if the increment is not unity. This
194 * will be ( N - 1 )*INCX too small for descending loops.
195 *
196 IF (INCX.LE.0) THEN
197 KX = 1 - (N-1)*INCX
198 ELSE IF (INCX.NE.1) THEN
199 KX = 1
200 END IF
201 *
202 * Start the operations. In this version the elements of A are
203 * accessed sequentially with one pass through A.
204 *
205 IF (LSAME(TRANS,'N')) THEN
206 *
207 * Form x := A*x.
208 *
209 IF (LSAME(UPLO,'U')) THEN
210 KPLUS1 = K + 1
211 IF (INCX.EQ.1) THEN
212 DO 20 J = 1,N
213 IF (X(J).NE.ZERO) THEN
214 TEMP = X(J)
215 L = KPLUS1 - J
216 DO 10 I = MAX(1,J-K),J - 1
217 X(I) = X(I) + TEMP*A(L+I,J)
218 10 CONTINUE
219 IF (NOUNIT) X(J) = X(J)*A(KPLUS1,J)
220 END IF
221 20 CONTINUE
222 ELSE
223 JX = KX
224 DO 40 J = 1,N
225 IF (X(JX).NE.ZERO) THEN
226 TEMP = X(JX)
227 IX = KX
228 L = KPLUS1 - J
229 DO 30 I = MAX(1,J-K),J - 1
230 X(IX) = X(IX) + TEMP*A(L+I,J)
231 IX = IX + INCX
232 30 CONTINUE
233 IF (NOUNIT) X(JX) = X(JX)*A(KPLUS1,J)
234 END IF
235 JX = JX + INCX
236 IF (J.GT.K) KX = KX + INCX
237 40 CONTINUE
238 END IF
239 ELSE
240 IF (INCX.EQ.1) THEN
241 DO 60 J = N,1,-1
242 IF (X(J).NE.ZERO) THEN
243 TEMP = X(J)
244 L = 1 - J
245 DO 50 I = MIN(N,J+K),J + 1,-1
246 X(I) = X(I) + TEMP*A(L+I,J)
247 50 CONTINUE
248 IF (NOUNIT) X(J) = X(J)*A(1,J)
249 END IF
250 60 CONTINUE
251 ELSE
252 KX = KX + (N-1)*INCX
253 JX = KX
254 DO 80 J = N,1,-1
255 IF (X(JX).NE.ZERO) THEN
256 TEMP = X(JX)
257 IX = KX
258 L = 1 - J
259 DO 70 I = MIN(N,J+K),J + 1,-1
260 X(IX) = X(IX) + TEMP*A(L+I,J)
261 IX = IX - INCX
262 70 CONTINUE
263 IF (NOUNIT) X(JX) = X(JX)*A(1,J)
264 END IF
265 JX = JX - INCX
266 IF ((N-J).GE.K) KX = KX - INCX
267 80 CONTINUE
268 END IF
269 END IF
270 ELSE
271 *
272 * Form x := A**T*x or x := A**H*x.
273 *
274 IF (LSAME(UPLO,'U')) THEN
275 KPLUS1 = K + 1
276 IF (INCX.EQ.1) THEN
277 DO 110 J = N,1,-1
278 TEMP = X(J)
279 L = KPLUS1 - J
280 IF (NOCONJ) THEN
281 IF (NOUNIT) TEMP = TEMP*A(KPLUS1,J)
282 DO 90 I = J - 1,MAX(1,J-K),-1
283 TEMP = TEMP + A(L+I,J)*X(I)
284 90 CONTINUE
285 ELSE
286 IF (NOUNIT) TEMP = TEMP*CONJG(A(KPLUS1,J))
287 DO 100 I = J - 1,MAX(1,J-K),-1
288 TEMP = TEMP + CONJG(A(L+I,J))*X(I)
289 100 CONTINUE
290 END IF
291 X(J) = TEMP
292 110 CONTINUE
293 ELSE
294 KX = KX + (N-1)*INCX
295 JX = KX
296 DO 140 J = N,1,-1
297 TEMP = X(JX)
298 KX = KX - INCX
299 IX = KX
300 L = KPLUS1 - J
301 IF (NOCONJ) THEN
302 IF (NOUNIT) TEMP = TEMP*A(KPLUS1,J)
303 DO 120 I = J - 1,MAX(1,J-K),-1
304 TEMP = TEMP + A(L+I,J)*X(IX)
305 IX = IX - INCX
306 120 CONTINUE
307 ELSE
308 IF (NOUNIT) TEMP = TEMP*CONJG(A(KPLUS1,J))
309 DO 130 I = J - 1,MAX(1,J-K),-1
310 TEMP = TEMP + CONJG(A(L+I,J))*X(IX)
311 IX = IX - INCX
312 130 CONTINUE
313 END IF
314 X(JX) = TEMP
315 JX = JX - INCX
316 140 CONTINUE
317 END IF
318 ELSE
319 IF (INCX.EQ.1) THEN
320 DO 170 J = 1,N
321 TEMP = X(J)
322 L = 1 - J
323 IF (NOCONJ) THEN
324 IF (NOUNIT) TEMP = TEMP*A(1,J)
325 DO 150 I = J + 1,MIN(N,J+K)
326 TEMP = TEMP + A(L+I,J)*X(I)
327 150 CONTINUE
328 ELSE
329 IF (NOUNIT) TEMP = TEMP*CONJG(A(1,J))
330 DO 160 I = J + 1,MIN(N,J+K)
331 TEMP = TEMP + CONJG(A(L+I,J))*X(I)
332 160 CONTINUE
333 END IF
334 X(J) = TEMP
335 170 CONTINUE
336 ELSE
337 JX = KX
338 DO 200 J = 1,N
339 TEMP = X(JX)
340 KX = KX + INCX
341 IX = KX
342 L = 1 - J
343 IF (NOCONJ) THEN
344 IF (NOUNIT) TEMP = TEMP*A(1,J)
345 DO 180 I = J + 1,MIN(N,J+K)
346 TEMP = TEMP + A(L+I,J)*X(IX)
347 IX = IX + INCX
348 180 CONTINUE
349 ELSE
350 IF (NOUNIT) TEMP = TEMP*CONJG(A(1,J))
351 DO 190 I = J + 1,MIN(N,J+K)
352 TEMP = TEMP + CONJG(A(L+I,J))*X(IX)
353 IX = IX + INCX
354 190 CONTINUE
355 END IF
356 X(JX) = TEMP
357 JX = JX + INCX
358 200 CONTINUE
359 END IF
360 END IF
361 END IF
362 *
363 RETURN
364 *
365 * End of CTBMV .
366 *
367 END