1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
|
*> \brief \b CHEMM
*
* =========== DOCUMENTATION ===========
*
* Online html documentation available at
* http://www.netlib.org/lapack/explore-html/
*
* Definition
* ==========
*
* SUBROUTINE CHEMM(SIDE,UPLO,M,N,ALPHA,A,LDA,B,LDB,BETA,C,LDC)
*
* .. Scalar Arguments ..
* COMPLEX ALPHA,BETA
* INTEGER LDA,LDB,LDC,M,N
* CHARACTER SIDE,UPLO
* ..
* .. Array Arguments ..
* COMPLEX A(LDA,*),B(LDB,*),C(LDC,*)
* ..
*
* Purpose
* =======
*
*>\details \b Purpose:
*>\verbatim
*>
*> CHEMM performs one of the matrix-matrix operations
*>
*> C := alpha*A*B + beta*C,
*>
*> or
*>
*> C := alpha*B*A + beta*C,
*>
*> where alpha and beta are scalars, A is an hermitian matrix and B and
*> C are m by n matrices.
*>
*>\endverbatim
*
* Arguments
* =========
*
*> \param[in] SIDE
*> \verbatim
*> SIDE is CHARACTER*1
*> On entry, SIDE specifies whether the hermitian matrix A
*> appears on the left or right in the operation as follows:
*> \endverbatim
*> \verbatim
*> SIDE = 'L' or 'l' C := alpha*A*B + beta*C,
*> \endverbatim
*> \verbatim
*> SIDE = 'R' or 'r' C := alpha*B*A + beta*C,
*> \endverbatim
*>
*> \param[in] UPLO
*> \verbatim
*> UPLO is CHARACTER*1
*> On entry, UPLO specifies whether the upper or lower
*> triangular part of the hermitian matrix A is to be
*> referenced as follows:
*> \endverbatim
*> \verbatim
*> UPLO = 'U' or 'u' Only the upper triangular part of the
*> hermitian matrix is to be referenced.
*> \endverbatim
*> \verbatim
*> UPLO = 'L' or 'l' Only the lower triangular part of the
*> hermitian matrix is to be referenced.
*> \endverbatim
*>
*> \param[in] M
*> \verbatim
*> M is INTEGER
*> On entry, M specifies the number of rows of the matrix C.
*> M must be at least zero.
*> \endverbatim
*>
*> \param[in] N
*> \verbatim
*> N is INTEGER
*> On entry, N specifies the number of columns of the matrix C.
*> N must be at least zero.
*> \endverbatim
*>
*> \param[in] ALPHA
*> \verbatim
*> ALPHA is COMPLEX
*> On entry, ALPHA specifies the scalar alpha.
*> \endverbatim
*>
*> \param[in] A
*> \verbatim
*> A is COMPLEX array of DIMENSION ( LDA, ka ), where ka is
*> m when SIDE = 'L' or 'l' and is n otherwise.
*> Before entry with SIDE = 'L' or 'l', the m by m part of
*> the array A must contain the hermitian matrix, such that
*> when UPLO = 'U' or 'u', the leading m by m upper triangular
*> part of the array A must contain the upper triangular part
*> of the hermitian matrix and the strictly lower triangular
*> part of A is not referenced, and when UPLO = 'L' or 'l',
*> the leading m by m lower triangular part of the array A
*> must contain the lower triangular part of the hermitian
*> matrix and the strictly upper triangular part of A is not
*> referenced.
*> Before entry with SIDE = 'R' or 'r', the n by n part of
*> the array A must contain the hermitian matrix, such that
*> when UPLO = 'U' or 'u', the leading n by n upper triangular
*> part of the array A must contain the upper triangular part
*> of the hermitian matrix and the strictly lower triangular
*> part of A is not referenced, and when UPLO = 'L' or 'l',
*> the leading n by n lower triangular part of the array A
*> must contain the lower triangular part of the hermitian
*> matrix and the strictly upper triangular part of A is not
*> referenced.
*> Note that the imaginary parts of the diagonal elements need
*> not be set, they are assumed to be zero.
*> \endverbatim
*>
*> \param[in] LDA
*> \verbatim
*> LDA is 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 ), otherwise LDA must be at
*> least max( 1, n ).
*> \endverbatim
*>
*> \param[in] B
*> \verbatim
*> B is COMPLEX array of DIMENSION ( LDB, n ).
*> Before entry, the leading m by n part of the array B must
*> contain the matrix B.
*> \endverbatim
*>
*> \param[in] LDB
*> \verbatim
*> LDB is 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 ).
*> \endverbatim
*>
*> \param[in] BETA
*> \verbatim
*> BETA is COMPLEX
*> On entry, BETA specifies the scalar beta. When BETA is
*> supplied as zero then C need not be set on input.
*> \endverbatim
*>
*> \param[in,out] C
*> \verbatim
*> C is COMPLEX array of DIMENSION ( LDC, n ).
*> Before entry, the leading m by n part of the array C must
*> contain the matrix C, except when beta is zero, in which
*> case C need not be set on entry.
*> On exit, the array C is overwritten by the m by n updated
*> matrix.
*> \endverbatim
*>
*> \param[in] LDC
*> \verbatim
*> LDC is INTEGER
*> On entry, LDC specifies the first dimension of C as declared
*> in the calling (sub) program. LDC must be at least
*> max( 1, m ).
*> \endverbatim
*>
*
* Authors
* =======
*
*> \author Univ. of Tennessee
*> \author Univ. of California Berkeley
*> \author Univ. of Colorado Denver
*> \author NAG Ltd.
*
*> \date November 2011
*
*> \ingroup complex_blas_level3
*
*
* Further Details
* ===============
*>\details \b Further \b Details
*> \verbatim
*>
*> 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.
*>
*> \endverbatim
*>
* =====================================================================
SUBROUTINE CHEMM(SIDE,UPLO,M,N,ALPHA,A,LDA,B,LDB,BETA,C,LDC)
*
* -- Reference BLAS level3 routine (version 3.4.0) --
* -- Reference BLAS is a software package provided by Univ. of Tennessee, --
* -- Univ. of California Berkeley, Univ. of Colorado Denver and NAG Ltd..--
* November 2011
*
* .. Scalar Arguments ..
COMPLEX ALPHA,BETA
INTEGER LDA,LDB,LDC,M,N
CHARACTER SIDE,UPLO
* ..
* .. Array Arguments ..
COMPLEX A(LDA,*),B(LDB,*),C(LDC,*)
* ..
*
* =====================================================================
*
* .. External Functions ..
LOGICAL LSAME
EXTERNAL LSAME
* ..
* .. External Subroutines ..
EXTERNAL XERBLA
* ..
* .. Intrinsic Functions ..
INTRINSIC CONJG,MAX,REAL
* ..
* .. Local Scalars ..
COMPLEX TEMP1,TEMP2
INTEGER I,INFO,J,K,NROWA
LOGICAL UPPER
* ..
* .. Parameters ..
COMPLEX ONE
PARAMETER (ONE= (1.0E+0,0.0E+0))
COMPLEX ZERO
PARAMETER (ZERO= (0.0E+0,0.0E+0))
* ..
*
* Set NROWA as the number of rows of A.
*
IF (LSAME(SIDE,'L')) THEN
NROWA = M
ELSE
NROWA = N
END IF
UPPER = LSAME(UPLO,'U')
*
* Test the input parameters.
*
INFO = 0
IF ((.NOT.LSAME(SIDE,'L')) .AND. (.NOT.LSAME(SIDE,'R'))) THEN
INFO = 1
ELSE IF ((.NOT.UPPER) .AND. (.NOT.LSAME(UPLO,'L'))) THEN
INFO = 2
ELSE IF (M.LT.0) THEN
INFO = 3
ELSE IF (N.LT.0) THEN
INFO = 4
ELSE IF (LDA.LT.MAX(1,NROWA)) THEN
INFO = 7
ELSE IF (LDB.LT.MAX(1,M)) THEN
INFO = 9
ELSE IF (LDC.LT.MAX(1,M)) THEN
INFO = 12
END IF
IF (INFO.NE.0) THEN
CALL XERBLA('CHEMM ',INFO)
RETURN
END IF
*
* Quick return if possible.
*
IF ((M.EQ.0) .OR. (N.EQ.0) .OR.
+ ((ALPHA.EQ.ZERO).AND. (BETA.EQ.ONE))) RETURN
*
* And when alpha.eq.zero.
*
IF (ALPHA.EQ.ZERO) THEN
IF (BETA.EQ.ZERO) THEN
DO 20 J = 1,N
DO 10 I = 1,M
C(I,J) = ZERO
10 CONTINUE
20 CONTINUE
ELSE
DO 40 J = 1,N
DO 30 I = 1,M
C(I,J) = BETA*C(I,J)
30 CONTINUE
40 CONTINUE
END IF
RETURN
END IF
*
* Start the operations.
*
IF (LSAME(SIDE,'L')) THEN
*
* Form C := alpha*A*B + beta*C.
*
IF (UPPER) THEN
DO 70 J = 1,N
DO 60 I = 1,M
TEMP1 = ALPHA*B(I,J)
TEMP2 = ZERO
DO 50 K = 1,I - 1
C(K,J) = C(K,J) + TEMP1*A(K,I)
TEMP2 = TEMP2 + B(K,J)*CONJG(A(K,I))
50 CONTINUE
IF (BETA.EQ.ZERO) THEN
C(I,J) = TEMP1*REAL(A(I,I)) + ALPHA*TEMP2
ELSE
C(I,J) = BETA*C(I,J) + TEMP1*REAL(A(I,I)) +
+ ALPHA*TEMP2
END IF
60 CONTINUE
70 CONTINUE
ELSE
DO 100 J = 1,N
DO 90 I = M,1,-1
TEMP1 = ALPHA*B(I,J)
TEMP2 = ZERO
DO 80 K = I + 1,M
C(K,J) = C(K,J) + TEMP1*A(K,I)
TEMP2 = TEMP2 + B(K,J)*CONJG(A(K,I))
80 CONTINUE
IF (BETA.EQ.ZERO) THEN
C(I,J) = TEMP1*REAL(A(I,I)) + ALPHA*TEMP2
ELSE
C(I,J) = BETA*C(I,J) + TEMP1*REAL(A(I,I)) +
+ ALPHA*TEMP2
END IF
90 CONTINUE
100 CONTINUE
END IF
ELSE
*
* Form C := alpha*B*A + beta*C.
*
DO 170 J = 1,N
TEMP1 = ALPHA*REAL(A(J,J))
IF (BETA.EQ.ZERO) THEN
DO 110 I = 1,M
C(I,J) = TEMP1*B(I,J)
110 CONTINUE
ELSE
DO 120 I = 1,M
C(I,J) = BETA*C(I,J) + TEMP1*B(I,J)
120 CONTINUE
END IF
DO 140 K = 1,J - 1
IF (UPPER) THEN
TEMP1 = ALPHA*A(K,J)
ELSE
TEMP1 = ALPHA*CONJG(A(J,K))
END IF
DO 130 I = 1,M
C(I,J) = C(I,J) + TEMP1*B(I,K)
130 CONTINUE
140 CONTINUE
DO 160 K = J + 1,N
IF (UPPER) THEN
TEMP1 = ALPHA*CONJG(A(J,K))
ELSE
TEMP1 = ALPHA*A(K,J)
END IF
DO 150 I = 1,M
C(I,J) = C(I,J) + TEMP1*B(I,K)
150 CONTINUE
160 CONTINUE
170 CONTINUE
END IF
*
RETURN
*
* End of CHEMM .
*
END
|