Scippy

SCIP

Solving Constraint Integer Programs

lpi_none.c
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1/* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */
2/* */
3/* This file is part of the program and library */
4/* SCIP --- Solving Constraint Integer Programs */
5/* */
6/* Copyright (c) 2002-2024 Zuse Institute Berlin (ZIB) */
7/* */
8/* Licensed under the Apache License, Version 2.0 (the "License"); */
9/* you may not use this file except in compliance with the License. */
10/* You may obtain a copy of the License at */
11/* */
12/* http://www.apache.org/licenses/LICENSE-2.0 */
13/* */
14/* Unless required by applicable law or agreed to in writing, software */
15/* distributed under the License is distributed on an "AS IS" BASIS, */
16/* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. */
17/* See the License for the specific language governing permissions and */
18/* limitations under the License. */
19/* */
20/* You should have received a copy of the Apache-2.0 license */
21/* along with SCIP; see the file LICENSE. If not visit scipopt.org. */
22/* */
23/* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */
24
25/**@file lpi_none.c
26 * @ingroup LPIS
27 * @brief dummy interface for the case no LP solver is needed
28 * @author Stefan Heinz
29 */
30
31/*--+----1----+----2----+----3----+----4----+----5----+----6----+----7----+----8----+----9----+----0----+----1----+----2*/
32
33#include <assert.h>
34
35#include "lpi/lpi.h"
36#include "scip/pub_message.h"
37
38#define LPINAME "NONE" /**< name of the LPI interface */
39#define LPIINFINITY 1e20 /**< infinity value */
40
41
42/* globally turn off lint warnings: */
43/*lint --e{715}*/
44
45/** LP interface
46 *
47 * Store several statistic values about the LP. These values are only needed in order to provide a rudimentary
48 * communication, e.g., there are asserts that check the number of rows and columns.
49 */
50struct SCIP_LPi
51{
52 int nrows; /**< number of rows */
53 int ncols; /**< number of columns */
54};
55
56
57/*
58 * Local Methods
59 */
60
61/** error handling method */
62static
64 void
65 )
66{ /*lint --e{2707}*/
67 SCIPerrorMessage("No LP solver available (LPS=none).\n");
68 SCIPerrorMessage("Ensure <lp/solvefreq = -1>; note that continuous variables might require an LP-solver.\n");
69 SCIPABORT();
70}
71
72/** error handling method */
73static
75 void
76 )
77{
78 SCIPerrorMessage("No LP solver available (LPS=none).\n");
79 SCIPerrorMessage("Ensure <lp/solvefreq = -1>; note that continuous variables might require an LP-solver.\n");
80}
81
82/*
83 * LP Interface Methods
84 */
85
86
87/*
88 * Miscellaneous Methods
89 */
90
91/**@name Miscellaneous Methods */
92/**@{ */
93
94/** gets name and version of LP solver */
96 void
97 )
98{
99 return LPINAME;
100}
101
102/** gets description of LP solver (developer, webpage, ...) */
104 void
105 )
106{
107 return "dummy LP solver interface which solely purpose is to resolve references at linking";
108}
109
110/** gets pointer for LP solver - use only with great care */
112 SCIP_LPI* lpi /**< pointer to an LP interface structure */
113 )
114{ /*lint --e{715}*/
115 return (void*) NULL;
116}
117
118/** pass integrality information to LP solver */
120 SCIP_LPI* lpi, /**< pointer to an LP interface structure */
121 int ncols, /**< length of integrality array */
122 int* intInfo /**< integrality array (0: continuous, 1: integer). May be NULL iff ncols is 0. */
123 )
124{ /*lint --e{715}*/
125 SCIPerrorMessage("SCIPlpiSetIntegralityInformation() has not been implemented yet.\n");
126 return SCIP_LPERROR;
127}
128
129/** informs about availability of a primal simplex solving method */
131 void
132 )
133{
134 return FALSE;
135}
136
137/** informs about availability of a dual simplex solving method */
139 void
140 )
141{
142 return FALSE;
143}
144
145/** informs about availability of a barrier solving method */
147 void
148 )
149{
150 return FALSE;
151}
152
153/**@} */
154
155
156
157
158/*
159 * LPI Creation and Destruction Methods
160 */
161
162/**@name LPI Creation and Destruction Methods */
163/**@{ */
164
165/** creates an LP problem object */
167 SCIP_LPI** lpi, /**< pointer to an LP interface structure */
168 SCIP_MESSAGEHDLR* messagehdlr, /**< message handler to use for printing messages, or NULL */
169 const char* name, /**< problem name */
170 SCIP_OBJSEN objsen /**< objective sense */
171 )
172{ /*lint --e{715}*/
173 assert(lpi != NULL);
174 assert(name != NULL);
175 SCIPdebugMessage("SCIPlpiCreate()\n");
176 SCIPdebugMessage("Note that there is no LP solver linked to the binary\n");
177
178 /* create empty LPI */
180 (*lpi)->nrows = 0;
181 (*lpi)->ncols = 0;
182
183 return SCIP_OKAY;
184}
185
186/** deletes an LP problem object */
188 SCIP_LPI** lpi /**< pointer to an LP interface structure */
189 )
190{ /*lint --e{715}*/
191 assert( lpi != NULL );
192 SCIPdebugMessage("SCIPlpiFree()\n");
193
194 BMSfreeMemory(lpi);
195
196 return SCIP_OKAY;
197}
198
199/**@} */
200
201
202
203
204/*
205 * Modification Methods
206 */
207
208/**@name Modification Methods */
209/**@{ */
210
211/** copies LP data with column matrix into LP solver */
213 SCIP_LPI* lpi, /**< LP interface structure */
214 SCIP_OBJSEN objsen, /**< objective sense */
215 int ncols, /**< number of columns */
216 const SCIP_Real* obj, /**< objective function values of columns */
217 const SCIP_Real* lb, /**< lower bounds of columns */
218 const SCIP_Real* ub, /**< upper bounds of columns */
219 char** colnames, /**< column names, or NULL */
220 int nrows, /**< number of rows */
221 const SCIP_Real* lhs, /**< left hand sides of rows */
222 const SCIP_Real* rhs, /**< right hand sides of rows */
223 char** rownames, /**< row names, or NULL */
224 int nnonz, /**< number of nonzero elements in the constraint matrix */
225 const int* beg, /**< start index of each column in ind- and val-array */
226 const int* ind, /**< row indices of constraint matrix entries */
227 const SCIP_Real* val /**< values of constraint matrix entries */
228 )
229{ /*lint --e{715}*/
230#ifndef NDEBUG
231 {
232 int j;
233 for( j = 0; j < nnonz; j++ )
234 assert( val[j] != 0 );
235 }
236#endif
237
238 assert( lpi != NULL );
239 assert(lhs != NULL);
240 assert(rhs != NULL);
241 assert(obj != NULL);
242 assert(lb != NULL);
243 assert(ub != NULL);
244 assert(beg != NULL);
245 assert(ind != NULL);
246 assert(val != NULL);
247
248 lpi->nrows = nrows;
249 lpi->ncols = ncols;
250 assert( lpi->nrows >= 0 );
251 assert( lpi->ncols >= 0 );
252
253 return SCIP_OKAY;
254}
255
256/** adds columns to the LP */
258 SCIP_LPI* lpi, /**< LP interface structure */
259 int ncols, /**< number of columns to be added */
260 const SCIP_Real* obj, /**< objective function values of new columns */
261 const SCIP_Real* lb, /**< lower bounds of new columns */
262 const SCIP_Real* ub, /**< upper bounds of new columns */
263 char** colnames, /**< column names, or NULL */
264 int nnonz, /**< number of nonzero elements to be added to the constraint matrix */
265 const int* beg, /**< start index of each column in ind- and val-array, or NULL if nnonz == 0 */
266 const int* ind, /**< row indices of constraint matrix entries, or NULL if nnonz == 0 */
267 const SCIP_Real* val /**< values of constraint matrix entries, or NULL if nnonz == 0 */
268 )
269{ /*lint --e{715}*/
270 assert( lpi != NULL );
271 assert( lpi->ncols >= 0 );
272 assert(obj != NULL);
273 assert(lb != NULL);
274 assert(ub != NULL);
275 assert(nnonz == 0 || beg != NULL);
276 assert(nnonz == 0 || ind != NULL);
277 assert(nnonz == 0 || val != NULL);
278 assert(nnonz >= 0);
279 assert(ncols >= 0);
280
281#ifndef NDEBUG
282 {
283 int j;
284 for( j = 0; j < nnonz; j++ )
285 {
286 assert( val[j] != 0.0 );
287 /* perform check that no new rows are added - this is forbidden */
288 assert( 0 <= ind[j] && ind[j] < lpi->nrows );
289 }
290 }
291#endif
292
293 lpi->ncols += ncols;
294
295 return SCIP_OKAY;
296}
297
298/** deletes all columns in the given range from LP */
300 SCIP_LPI* lpi, /**< LP interface structure */
301 int firstcol, /**< first column to be deleted */
302 int lastcol /**< last column to be deleted */
303 )
304{ /*lint --e{715}*/
305 assert( lpi != NULL );
306 assert( lpi->ncols >= 0 );
307
308 lpi->ncols -= lastcol - firstcol + 1;
309 assert( lpi->ncols >= 0 );
310
311 return SCIP_OKAY;
312}
313
314/** deletes columns from SCIP_LP; the new position of a column must not be greater that its old position */
316 SCIP_LPI* lpi, /**< LP interface structure */
317 int* dstat /**< deletion status of columns
318 * input: 1 if column should be deleted, 0 if not
319 * output: new position of column, -1 if column was deleted */
320 )
321{ /*lint --e{715}*/
322 int cnt = 0;
323 int j;
324
325 assert( lpi != NULL );
326 assert( dstat != NULL );
327 assert( lpi->ncols >= 0 );
328
329 for (j = 0; j < lpi->ncols; ++j)
330 {
331 if ( dstat[j] )
332 {
333 ++cnt;
334 dstat[j] = -1;
335 }
336 else
337 dstat[j] = cnt;
338 }
339 lpi->ncols -= cnt;
340 assert( lpi->ncols >= 0 );
341
342 return SCIP_OKAY;
343}
344
345/** adds rows to the LP */
347 SCIP_LPI* lpi, /**< LP interface structure */
348 int nrows, /**< number of rows to be added */
349 const SCIP_Real* lhs, /**< left hand sides of new rows */
350 const SCIP_Real* rhs, /**< right hand sides of new rows */
351 char** rownames, /**< row names, or NULL */
352 int nnonz, /**< number of nonzero elements to be added to the constraint matrix */
353 const int* beg, /**< start index of each row in ind- and val-array, or NULL if nnonz == 0 */
354 const int* ind, /**< column indices of constraint matrix entries, or NULL if nnonz == 0 */
355 const SCIP_Real* val /**< values of constraint matrix entries, or NULL if nnonz == 0 */
356 )
357{ /*lint --e{715}*/
358 assert( lpi != NULL );
359 assert( lpi->nrows >= 0 );
360 assert(lhs != NULL);
361 assert(rhs != NULL);
362 assert(nnonz == 0 || beg != NULL);
363 assert(nnonz == 0 || ind != NULL);
364 assert(nnonz == 0 || val != NULL);
365
366#ifndef NDEBUG
367 /* perform check that no new columns are added - this is forbidden */
368 {
369 int j;
370 for (j = 0; j < nnonz; ++j)
371 {
372 assert( val[j] != 0.0 );
373 assert( 0 <= ind[j] && ind[j] < lpi->ncols );
374 }
375 }
376#endif
377
378 lpi->nrows += nrows;
379
380 return SCIP_OKAY;
381}
382
383/** deletes all rows in the given range from LP */
385 SCIP_LPI* lpi, /**< LP interface structure */
386 int firstrow, /**< first row to be deleted */
387 int lastrow /**< last row to be deleted */
388 )
389{ /*lint --e{715}*/
390 assert( lpi != NULL );
391 assert( lpi->nrows >= 0 );
392
393 lpi->nrows -= lastrow - firstrow + 1;
394 assert( lpi->nrows >= 0 );
395
396 return SCIP_OKAY;
397}
398
399/** deletes rows from SCIP_LP; the new position of a row must not be greater that its old position */
401 SCIP_LPI* lpi, /**< LP interface structure */
402 int* dstat /**< deletion status of rows
403 * input: 1 if row should be deleted, 0 if not
404 * output: new position of row, -1 if row was deleted */
405 )
406{ /*lint --e{715}*/
407 int cnt = 0;
408 int i;
409
410 assert( lpi != NULL );
411 assert( dstat != NULL );
412 assert( lpi->nrows >= 0 );
413
414 for (i = 0; i < lpi->nrows; ++i)
415 {
416 if ( dstat[i] )
417 {
418 ++cnt;
419 dstat[i] = -1;
420 }
421 else
422 dstat[i] = cnt;
423 }
424 lpi->nrows -= cnt;
425 assert( lpi->nrows >= 0 );
426
427 return SCIP_OKAY;
428}
429
430/** clears the whole LP */
432 SCIP_LPI* lpi /**< LP interface structure */
433 )
434{ /*lint --e{715}*/
435 assert( lpi != NULL );
436 assert( lpi->nrows >= 0 );
437 assert( lpi->ncols >= 0 );
438
439 lpi->nrows = 0;
440 lpi->ncols = 0;
441
442 return SCIP_OKAY;
443}
444
445/** changes lower and upper bounds of columns */
447 SCIP_LPI* lpi, /**< LP interface structure */
448 int ncols, /**< number of columns to change bounds for */
449 const int* ind, /**< column indices or NULL if ncols is zero */
450 const SCIP_Real* lb, /**< values for the new lower bounds or NULL if ncols is zero */
451 const SCIP_Real* ub /**< values for the new upper bounds or NULL if ncols is zero */
452 )
453{ /*lint --e{715}*/
454 int j;
455
456 assert(ncols == 0 || (ind != NULL && lb != NULL && ub != NULL));
457
458 if( ncols <= 0 )
459 return SCIP_OKAY;
460
461 for (j = 0; j < ncols; ++j)
462 {
463 if ( SCIPlpiIsInfinity(lpi, lb[j]) )
464 {
465 SCIPerrorMessage("LP Error: fixing lower bound for variable %d to infinity.\n", ind[j]);
466 return SCIP_LPERROR;
467 }
468 if ( SCIPlpiIsInfinity(lpi, -ub[j]) )
469 {
470 SCIPerrorMessage("LP Error: fixing upper bound for variable %d to -infinity.\n", ind[j]);
471 return SCIP_LPERROR;
472 }
473 }
474
475 return SCIP_OKAY;
476}
477
478/** changes left and right hand sides of rows */
480 SCIP_LPI* lpi, /**< LP interface structure */
481 int nrows, /**< number of rows to change sides for */
482 const int* ind, /**< row indices */
483 const SCIP_Real* lhs, /**< new values for left hand sides */
484 const SCIP_Real* rhs /**< new values for right hand sides */
485 )
486{ /*lint --e{715}*/
487 assert(lpi != NULL);
488 assert(ind != NULL);
489 assert(lhs != NULL);
490 assert(rhs != NULL);
491 return SCIP_OKAY;
492}
493
494/** changes a single coefficient */
496 SCIP_LPI* lpi, /**< LP interface structure */
497 int row, /**< row number of coefficient to change */
498 int col, /**< column number of coefficient to change */
499 SCIP_Real newval /**< new value of coefficient */
500 )
501{ /*lint --e{715}*/
502 assert(lpi != NULL);
503 return SCIP_OKAY;
504}
505
506/** changes the objective sense */
508 SCIP_LPI* lpi, /**< LP interface structure */
509 SCIP_OBJSEN objsen /**< new objective sense */
510 )
511{ /*lint --e{715}*/
512 assert(lpi != NULL);
513 return SCIP_OKAY;
514}
515
516/** changes objective values of columns in the LP */
518 SCIP_LPI* lpi, /**< LP interface structure */
519 int ncols, /**< number of columns to change objective value for */
520 const int* ind, /**< column indices to change objective value for */
521 const SCIP_Real* obj /**< new objective values for columns */
522 )
523{ /*lint --e{715}*/
524 assert(lpi != NULL);
525 assert(ind != NULL);
526 assert(obj != NULL);
527 return SCIP_OKAY;
528}
529
530/** multiplies a row with a non-zero scalar; for negative scalars, the row's sense is switched accordingly */
532 SCIP_LPI* lpi, /**< LP interface structure */
533 int row, /**< row number to scale */
534 SCIP_Real scaleval /**< scaling multiplier */
535 )
536{ /*lint --e{715}*/
537 assert(lpi != NULL);
538 return SCIP_OKAY;
539}
540
541/** multiplies a column with a non-zero scalar; the objective value is multiplied with the scalar, and the bounds
542 * are divided by the scalar; for negative scalars, the column's bounds are switched
543 */
545 SCIP_LPI* lpi, /**< LP interface structure */
546 int col, /**< column number to scale */
547 SCIP_Real scaleval /**< scaling multiplier */
548 )
549{ /*lint --e{715}*/
550 assert(lpi != NULL);
551 return SCIP_OKAY;
552}
553
554/**@} */
555
556
557
558
559/*
560 * Data Accessing Methods
561 */
562
563/**@name Data Accessing Methods */
564/**@{ */
565
566/** gets the number of rows in the LP */
568 SCIP_LPI* lpi, /**< LP interface structure */
569 int* nrows /**< pointer to store the number of rows */
570 )
571{ /*lint --e{715}*/
572 assert( lpi != NULL );
573 assert( nrows != NULL );
574 assert( lpi->nrows >= 0 );
575
576 *nrows = lpi->nrows;
577
578 return SCIP_OKAY;
579}
580
581/** gets the number of columns in the LP */
583 SCIP_LPI* lpi, /**< LP interface structure */
584 int* ncols /**< pointer to store the number of cols */
585 )
586{ /*lint --e{715}*/
587 assert( lpi != NULL );
588 assert( ncols != NULL );
589 assert( lpi->ncols >= 0 );
590
591 *ncols = lpi->ncols;
592
593 return SCIP_OKAY;
594}
595
596/** gets the number of nonzero elements in the LP constraint matrix */
598 SCIP_LPI* lpi, /**< LP interface structure */
599 int* nnonz /**< pointer to store the number of nonzeros */
600 )
601{ /*lint --e{715}*/
602 assert(nnonz != NULL);
603 assert(lpi != NULL);
604 errorMessage();
605 return SCIP_PLUGINNOTFOUND;
606}
607
608/** gets columns from LP problem object; the arrays have to be large enough to store all values
609 * Either both, lb and ub, have to be NULL, or both have to be non-NULL,
610 * either nnonz, beg, ind, and val have to be NULL, or all of them have to be non-NULL.
611 */
613 SCIP_LPI* lpi, /**< LP interface structure */
614 int firstcol, /**< first column to get from LP */
615 int lastcol, /**< last column to get from LP */
616 SCIP_Real* lb, /**< buffer to store the lower bound vector, or NULL */
617 SCIP_Real* ub, /**< buffer to store the upper bound vector, or NULL */
618 int* nnonz, /**< pointer to store the number of nonzero elements returned, or NULL */
619 int* beg, /**< buffer to store start index of each column in ind- and val-array, or NULL */
620 int* ind, /**< buffer to store row indices of constraint matrix entries, or NULL */
621 SCIP_Real* val /**< buffer to store values of constraint matrix entries, or NULL */
622 )
623{ /*lint --e{715}*/
624 errorMessage();
625 return SCIP_PLUGINNOTFOUND;
626}
627
628/** gets rows from LP problem object; the arrays have to be large enough to store all values.
629 * Either both, lhs and rhs, have to be NULL, or both have to be non-NULL,
630 * either nnonz, beg, ind, and val have to be NULL, or all of them have to be non-NULL.
631 */
633 SCIP_LPI* lpi, /**< LP interface structure */
634 int firstrow, /**< first row to get from LP */
635 int lastrow, /**< last row to get from LP */
636 SCIP_Real* lhs, /**< buffer to store left hand side vector, or NULL */
637 SCIP_Real* rhs, /**< buffer to store right hand side vector, or NULL */
638 int* nnonz, /**< pointer to store the number of nonzero elements returned, or NULL */
639 int* beg, /**< buffer to store start index of each row in ind- and val-array, or NULL */
640 int* ind, /**< buffer to store column indices of constraint matrix entries, or NULL */
641 SCIP_Real* val /**< buffer to store values of constraint matrix entries, or NULL */
642 )
643{ /*lint --e{715}*/
644 errorMessage();
645 return SCIP_PLUGINNOTFOUND;
646}
647
648/** gets column names */
650 SCIP_LPI* lpi, /**< LP interface structure */
651 int firstcol, /**< first column to get name from LP */
652 int lastcol, /**< last column to get name from LP */
653 char** colnames, /**< pointers to column names (of size at least lastcol-firstcol+1) or NULL if namestoragesize is zero */
654 char* namestorage, /**< storage for col names or NULL if namestoragesize is zero */
655 int namestoragesize, /**< size of namestorage (if 0, storageleft returns the storage needed) */
656 int* storageleft /**< amount of storage left (if < 0 the namestorage was not big enough) or NULL if namestoragesize is zero */
657 )
658{ /*lint --e{715}*/
659 assert(lpi != NULL);
660 assert(colnames != NULL || namestoragesize == 0);
661 assert(namestorage != NULL || namestoragesize == 0);
662 assert(namestoragesize >= 0);
663 assert(storageleft != NULL);
664 errorMessage();
665 return SCIP_PLUGINNOTFOUND;
666}
667
668/** gets row names */
670 SCIP_LPI* lpi, /**< LP interface structure */
671 int firstrow, /**< first row to get name from LP */
672 int lastrow, /**< last row to get name from LP */
673 char** rownames, /**< pointers to row names (of size at least lastrow-firstrow+1) or NULL if namestoragesize is zero */
674 char* namestorage, /**< storage for row names or NULL if namestoragesize is zero */
675 int namestoragesize, /**< size of namestorage (if 0, -storageleft returns the storage needed) */
676 int* storageleft /**< amount of storage left (if < 0 the namestorage was not big enough) or NULL if namestoragesize is zero */
677 )
678{ /*lint --e{715}*/
679 assert(lpi != NULL);
680 assert(rownames != NULL || namestoragesize == 0);
681 assert(namestorage != NULL || namestoragesize == 0);
682 assert(namestoragesize >= 0);
683 assert(storageleft != NULL);
684 errorMessage();
685 return SCIP_PLUGINNOTFOUND;
686}
687
688/** gets the objective sense of the LP */
690 SCIP_LPI* lpi, /**< LP interface structure */
691 SCIP_OBJSEN* objsen /**< pointer to store objective sense */
692 )
693{ /*lint --e{715}*/
694 errorMessage();
695 return SCIP_PLUGINNOTFOUND;
696}
697
698/** gets objective coefficients from LP problem object */
700 SCIP_LPI* lpi, /**< LP interface structure */
701 int firstcol, /**< first column to get objective coefficient for */
702 int lastcol, /**< last column to get objective coefficient for */
703 SCIP_Real* vals /**< array to store objective coefficients */
704 )
705{ /*lint --e{715}*/
706 assert(lpi != NULL);
707 assert(firstcol <= lastcol);
708 assert(vals != NULL);
709 errorMessage();
710 return SCIP_PLUGINNOTFOUND;
711}
712
713/** gets current bounds from LP problem object */
715 SCIP_LPI* lpi, /**< LP interface structure */
716 int firstcol, /**< first column to get bounds for */
717 int lastcol, /**< last column to get bounds for */
718 SCIP_Real* lbs, /**< array to store lower bound values, or NULL */
719 SCIP_Real* ubs /**< array to store upper bound values, or NULL */
720 )
721{ /*lint --e{715}*/
722 assert(lpi != NULL);
723 assert(firstcol <= lastcol);
724 errorMessage();
725 return SCIP_PLUGINNOTFOUND;
726}
727
728/** gets current row sides from LP problem object */
730 SCIP_LPI* lpi, /**< LP interface structure */
731 int firstrow, /**< first row to get sides for */
732 int lastrow, /**< last row to get sides for */
733 SCIP_Real* lhss, /**< array to store left hand side values, or NULL */
734 SCIP_Real* rhss /**< array to store right hand side values, or NULL */
735 )
736{ /*lint --e{715}*/
737 assert(lpi != NULL);
738 assert(firstrow <= lastrow);
739 errorMessage();
740 return SCIP_PLUGINNOTFOUND;
741}
742
743/** gets a single coefficient */
745 SCIP_LPI* lpi, /**< LP interface structure */
746 int row, /**< row number of coefficient */
747 int col, /**< column number of coefficient */
748 SCIP_Real* val /**< pointer to store the value of the coefficient */
749 )
750{ /*lint --e{715}*/
751 assert(lpi != NULL);
752 assert(val != NULL);
753 errorMessage();
754 return SCIP_PLUGINNOTFOUND;
755}
756
757/**@} */
758
759
760
761
762/*
763 * Solving Methods
764 */
765
766/**@name Solving Methods */
767/**@{ */
768
769/** calls primal simplex to solve the LP */
771 SCIP_LPI* lpi /**< LP interface structure */
772 )
773{ /*lint --e{715}*/
774 assert(lpi != NULL);
775 errorMessage();
776 return SCIP_PLUGINNOTFOUND;
777}
778
779/** calls dual simplex to solve the LP */
781 SCIP_LPI* lpi /**< LP interface structure */
782 )
783{ /*lint --e{715}*/
784 assert(lpi != NULL);
785 errorMessage();
786 return SCIP_PLUGINNOTFOUND;
787}
788
789/** calls barrier or interior point algorithm to solve the LP with crossover to simplex basis */
791 SCIP_LPI* lpi, /**< LP interface structure */
792 SCIP_Bool crossover /**< perform crossover */
793 )
794{ /*lint --e{715}*/
795 assert(lpi != NULL);
796 errorMessage();
797 return SCIP_PLUGINNOTFOUND;
798}
799
800/** start strong branching - call before any strong branching */
802 SCIP_LPI* lpi /**< LP interface structure */
803 )
804{ /*lint --e{715}*/
805 assert(lpi != NULL);
806 return SCIP_OKAY;
807}
808
809/** end strong branching - call after any strong branching */
811 SCIP_LPI* lpi /**< LP interface structure */
812 )
813{ /*lint --e{715}*/
814 assert(lpi != NULL);
815 return SCIP_OKAY;
816}
817
818/** performs strong branching iterations on one @b fractional candidate */
820 SCIP_LPI* lpi, /**< LP interface structure */
821 int col, /**< column to apply strong branching on */
822 SCIP_Real psol, /**< fractional current primal solution value of column */
823 int itlim, /**< iteration limit for strong branchings */
824 SCIP_Real* down, /**< stores dual bound after branching column down */
825 SCIP_Real* up, /**< stores dual bound after branching column up */
826 SCIP_Bool* downvalid, /**< stores whether the returned down value is a valid dual bound;
827 * otherwise, it can only be used as an estimate value */
828 SCIP_Bool* upvalid, /**< stores whether the returned up value is a valid dual bound;
829 * otherwise, it can only be used as an estimate value */
830 int* iter /**< stores total number of strong branching iterations, or -1; may be NULL */
831 )
832{ /*lint --e{715}*/
833 assert(lpi != NULL);
834 assert( down != NULL );
835 assert( up != NULL );
836 assert( downvalid != NULL );
837 assert( upvalid != NULL );
838 errorMessage();
839 return SCIP_PLUGINNOTFOUND;
840}
841
842/** performs strong branching iterations on given @b fractional candidates */
844 SCIP_LPI* lpi, /**< LP interface structure */
845 int* cols, /**< columns to apply strong branching on */
846 int ncols, /**< number of columns */
847 SCIP_Real* psols, /**< fractional current primal solution values of columns */
848 int itlim, /**< iteration limit for strong branchings */
849 SCIP_Real* down, /**< stores dual bounds after branching columns down */
850 SCIP_Real* up, /**< stores dual bounds after branching columns up */
851 SCIP_Bool* downvalid, /**< stores whether the returned down values are valid dual bounds;
852 * otherwise, they can only be used as an estimate values */
853 SCIP_Bool* upvalid, /**< stores whether the returned up values are a valid dual bounds;
854 * otherwise, they can only be used as an estimate values */
855 int* iter /**< stores total number of strong branching iterations, or -1; may be NULL */
856 )
857{ /*lint --e{715}*/
858 assert(lpi != NULL);
859 assert( cols != NULL );
860 assert( psols != NULL );
861 assert( down != NULL );
862 assert( up != NULL );
863 assert( downvalid != NULL );
864 assert( upvalid != NULL );
865 errorMessage();
866 return SCIP_PLUGINNOTFOUND;
867}
868
869/** performs strong branching iterations on one candidate with @b integral value */
871 SCIP_LPI* lpi, /**< LP interface structure */
872 int col, /**< column to apply strong branching on */
873 SCIP_Real psol, /**< current integral primal solution value of column */
874 int itlim, /**< iteration limit for strong branchings */
875 SCIP_Real* down, /**< stores dual bound after branching column down */
876 SCIP_Real* up, /**< stores dual bound after branching column up */
877 SCIP_Bool* downvalid, /**< stores whether the returned down value is a valid dual bound;
878 * otherwise, it can only be used as an estimate value */
879 SCIP_Bool* upvalid, /**< stores whether the returned up value is a valid dual bound;
880 * otherwise, it can only be used as an estimate value */
881 int* iter /**< stores total number of strong branching iterations, or -1; may be NULL */
882 )
883{ /*lint --e{715}*/
884 assert(lpi != NULL);
885 assert( down != NULL );
886 assert( up != NULL );
887 assert( downvalid != NULL );
888 assert( upvalid != NULL );
889 errorMessage();
890 return SCIP_PLUGINNOTFOUND;
891}
892
893/** performs strong branching iterations on given candidates with @b integral values */
895 SCIP_LPI* lpi, /**< LP interface structure */
896 int* cols, /**< columns to apply strong branching on */
897 int ncols, /**< number of columns */
898 SCIP_Real* psols, /**< current integral primal solution values of columns */
899 int itlim, /**< iteration limit for strong branchings */
900 SCIP_Real* down, /**< stores dual bounds after branching columns down */
901 SCIP_Real* up, /**< stores dual bounds after branching columns up */
902 SCIP_Bool* downvalid, /**< stores whether the returned down values are valid dual bounds;
903 * otherwise, they can only be used as an estimate values */
904 SCIP_Bool* upvalid, /**< stores whether the returned up values are a valid dual bounds;
905 * otherwise, they can only be used as an estimate values */
906 int* iter /**< stores total number of strong branching iterations, or -1; may be NULL */
907 )
908{ /*lint --e{715}*/
909 assert(lpi != NULL);
910 assert( cols != NULL );
911 assert( psols != NULL );
912 assert( down != NULL );
913 assert( up != NULL );
914 assert( downvalid != NULL );
915 assert( upvalid != NULL );
916 errorMessage();
917 return SCIP_PLUGINNOTFOUND;
918}
919/**@} */
920
921
922
923
924/*
925 * Solution Information Methods
926 */
927
928/**@name Solution Information Methods */
929/**@{ */
930
931/** returns whether a solve method was called after the last modification of the LP */
933 SCIP_LPI* lpi /**< LP interface structure */
934 )
935{ /*lint --e{715}*/
936 assert(lpi != NULL);
938 return FALSE;
939}
940
941/** gets information about primal and dual feasibility of the current LP solution
942 *
943 * The feasibility information is with respect to the last solving call and it is only relevant if SCIPlpiWasSolved()
944 * returns true. If the LP is changed, this information might be invalidated.
945 *
946 * Note that @a primalfeasible and @a dualfeasible should only return true if the solver has proved the respective LP to
947 * be feasible. Thus, the return values should be equal to the values of SCIPlpiIsPrimalFeasible() and
948 * SCIPlpiIsDualFeasible(), respectively. Note that if feasibility cannot be proved, they should return false (even if
949 * the problem might actually be feasible).
950 */
952 SCIP_LPI* lpi, /**< LP interface structure */
953 SCIP_Bool* primalfeasible, /**< pointer to store primal feasibility status */
954 SCIP_Bool* dualfeasible /**< pointer to store dual feasibility status */
955 )
956{ /*lint --e{715}*/
957 assert(lpi != NULL);
958 assert(primalfeasible != NULL);
959 assert(dualfeasible != NULL);
960 errorMessage();
961 return SCIP_PLUGINNOTFOUND;
962}
963
964/** returns TRUE iff LP is proven to have a primal unbounded ray (but not necessary a primal feasible point);
965 * this does not necessarily mean, that the solver knows and can return the primal ray
966 */
968 SCIP_LPI* lpi /**< LP interface structure */
969 )
970{ /*lint --e{715}*/
971 assert(lpi != NULL);
973 return FALSE;
974}
975
976/** returns TRUE iff LP is proven to have a primal unbounded ray (but not necessary a primal feasible point),
977 * and the solver knows and can return the primal ray
978 */
980 SCIP_LPI* lpi /**< LP interface structure */
981 )
982{ /*lint --e{715}*/
983 assert(lpi != NULL);
985 return FALSE;
986}
987
988/** returns TRUE iff LP is proven to be primal unbounded */
990 SCIP_LPI* lpi /**< LP interface structure */
991 )
992{ /*lint --e{715}*/
993 assert(lpi != NULL);
995 return FALSE;
996}
997
998/** returns TRUE iff LP is proven to be primal infeasible */
1000 SCIP_LPI* lpi /**< LP interface structure */
1001 )
1002{ /*lint --e{715}*/
1003 assert(lpi != NULL);
1005 return FALSE;
1006}
1007
1008/** returns TRUE iff LP is proven to be primal feasible */
1010 SCIP_LPI* lpi /**< LP interface structure */
1011 )
1012{ /*lint --e{715}*/
1013 assert(lpi != NULL);
1015 return FALSE;
1016}
1017
1018/** returns TRUE iff LP is proven to have a dual unbounded ray (but not necessary a dual feasible point);
1019 * this does not necessarily mean, that the solver knows and can return the dual ray
1020 */
1022 SCIP_LPI* lpi /**< LP interface structure */
1023 )
1024{ /*lint --e{715}*/
1025 assert(lpi != NULL);
1027 return FALSE;
1028}
1029
1030/** returns TRUE iff LP is proven to have a dual unbounded ray (but not necessary a dual feasible point),
1031 * and the solver knows and can return the dual ray
1032 */
1034 SCIP_LPI* lpi /**< LP interface structure */
1035 )
1036{ /*lint --e{715}*/
1037 assert(lpi != NULL);
1039 return FALSE;
1040}
1041
1042/** returns TRUE iff LP is proven to be dual unbounded */
1044 SCIP_LPI* lpi /**< LP interface structure */
1045 )
1046{ /*lint --e{715}*/
1047 assert(lpi != NULL);
1049 return FALSE;
1050}
1051
1052/** returns TRUE iff LP is proven to be dual infeasible */
1054 SCIP_LPI* lpi /**< LP interface structure */
1055 )
1056{ /*lint --e{715}*/
1057 assert(lpi != NULL);
1059 return FALSE;
1060}
1061
1062/** returns TRUE iff LP is proven to be dual feasible */
1064 SCIP_LPI* lpi /**< LP interface structure */
1065 )
1066{ /*lint --e{715}*/
1067 assert(lpi != NULL);
1069 return FALSE;
1070}
1071
1072/** returns TRUE iff LP was solved to optimality */
1074 SCIP_LPI* lpi /**< LP interface structure */
1075 )
1076{ /*lint --e{715}*/
1077 assert(lpi != NULL);
1079 return FALSE;
1080}
1081
1082/** returns TRUE iff current LP solution is stable
1083 *
1084 * This function should return true if the solution is reliable, i.e., feasible and optimal (or proven
1085 * infeasible/unbounded) with respect to the original problem. The optimality status might be with respect to a scaled
1086 * version of the problem, but the solution might not be feasible to the unscaled original problem; in this case,
1087 * SCIPlpiIsStable() should return false.
1088 */
1090 SCIP_LPI* lpi /**< LP interface structure */
1091 )
1092{ /*lint --e{715}*/
1093 assert(lpi != NULL);
1095 return FALSE;
1096}
1097
1098/** returns TRUE iff the objective limit was reached */
1100 SCIP_LPI* lpi /**< LP interface structure */
1101 )
1102{ /*lint --e{715}*/
1103 assert(lpi != NULL);
1105 return FALSE;
1106}
1107
1108/** returns TRUE iff the iteration limit was reached */
1110 SCIP_LPI* lpi /**< LP interface structure */
1111 )
1112{ /*lint --e{715}*/
1113 assert(lpi != NULL);
1115 return FALSE;
1116}
1117
1118/** returns TRUE iff the time limit was reached */
1120 SCIP_LPI* lpi /**< LP interface structure */
1121 )
1122{ /*lint --e{715}*/
1123 assert(lpi != NULL);
1125 return FALSE;
1126}
1127
1128/** returns the internal solution status of the solver */
1130 SCIP_LPI* lpi /**< LP interface structure */
1131 )
1132{ /*lint --e{715}*/
1133 assert(lpi != NULL);
1135 return FALSE;
1136}
1137
1138/** tries to reset the internal status of the LP solver in order to ignore an instability of the last solving call */
1140 SCIP_LPI* lpi, /**< LP interface structure */
1141 SCIP_Bool* success /**< pointer to store, whether the instability could be ignored */
1142 )
1143{ /*lint --e{715}*/
1144 assert(lpi != NULL);
1145 assert(success != NULL);
1146 errorMessage();
1147 return SCIP_PLUGINNOTFOUND;
1148}
1149
1150/** gets objective value of solution */
1152 SCIP_LPI* lpi, /**< LP interface structure */
1153 SCIP_Real* objval /**< stores the objective value */
1154 )
1155{ /*lint --e{715}*/
1156 assert(lpi != NULL);
1157 assert(objval != NULL);
1158 errorMessage();
1159 return SCIP_PLUGINNOTFOUND;
1160}
1161
1162/** gets primal and dual solution vectors for feasible LPs
1163 *
1164 * Before calling this function, the caller must ensure that the LP has been solved to optimality, i.e., that
1165 * SCIPlpiIsOptimal() returns true.
1166 */
1168 SCIP_LPI* lpi, /**< LP interface structure */
1169 SCIP_Real* objval, /**< stores the objective value, may be NULL if not needed */
1170 SCIP_Real* primsol, /**< primal solution vector, may be NULL if not needed */
1171 SCIP_Real* dualsol, /**< dual solution vector, may be NULL if not needed */
1172 SCIP_Real* activity, /**< row activity vector, may be NULL if not needed */
1173 SCIP_Real* redcost /**< reduced cost vector, may be NULL if not needed */
1174 )
1175{ /*lint --e{715}*/
1176 assert(lpi != NULL);
1177 errorMessage();
1178 return SCIP_PLUGINNOTFOUND;
1179}
1180
1181/** gets primal ray for unbounded LPs */
1183 SCIP_LPI* lpi, /**< LP interface structure */
1184 SCIP_Real* ray /**< primal ray */
1185 )
1186{ /*lint --e{715}*/
1187 assert(lpi != NULL);
1188 assert(ray != NULL);
1189 errorMessage();
1190 return SCIP_PLUGINNOTFOUND;
1191}
1192
1193/** gets dual Farkas proof for infeasibility */
1195 SCIP_LPI* lpi, /**< LP interface structure */
1196 SCIP_Real* dualfarkas /**< dual Farkas row multipliers */
1197 )
1198{ /*lint --e{715}*/
1199 assert(lpi != NULL);
1200 assert(dualfarkas != NULL);
1201 errorMessage();
1202 return SCIP_PLUGINNOTFOUND;
1203}
1204
1205/** gets the number of LP iterations of the last solve call */
1207 SCIP_LPI* lpi, /**< LP interface structure */
1208 int* iterations /**< pointer to store the number of iterations of the last solve call */
1209 )
1210{ /*lint --e{715}*/
1211 assert(lpi != NULL);
1212 assert(iterations != NULL);
1213 errorMessage();
1214 return SCIP_PLUGINNOTFOUND;
1215}
1216
1217/** gets information about the quality of an LP solution
1218 *
1219 * Such information is usually only available, if also a (maybe not optimal) solution is available.
1220 * The LPI should return SCIP_INVALID for @p quality, if the requested quantity is not available.
1221 */
1223 SCIP_LPI* lpi, /**< LP interface structure */
1224 SCIP_LPSOLQUALITY qualityindicator, /**< indicates which quality should be returned */
1225 SCIP_Real* quality /**< pointer to store quality number */
1226 )
1227{ /*lint --e{715}*/
1228 assert(lpi != NULL);
1229 assert(quality != NULL);
1230
1231 *quality = SCIP_INVALID;
1232
1233 return SCIP_OKAY;
1234}
1235
1236/**@} */
1237
1238
1239
1240
1241/*
1242 * LP Basis Methods
1243 */
1244
1245/**@name LP Basis Methods */
1246/**@{ */
1247
1248/** gets current basis status for columns and rows; arrays must be large enough to store the basis status */
1250 SCIP_LPI* lpi, /**< LP interface structure */
1251 int* cstat, /**< array to store column basis status, or NULL */
1252 int* rstat /**< array to store row basis status, or NULL */
1253 )
1254{ /*lint --e{715}*/
1255 assert(lpi != NULL);
1256 errorMessage();
1257 return SCIP_PLUGINNOTFOUND;
1258}
1259
1260/** sets current basis status for columns and rows */
1262 SCIP_LPI* lpi, /**< LP interface structure */
1263 const int* cstat, /**< array with column basis status */
1264 const int* rstat /**< array with row basis status */
1265 )
1266{ /*lint --e{715}*/
1267 assert(lpi != NULL);
1268 assert(cstat != NULL);
1269 assert(rstat != NULL);
1270 errorMessage();
1271 return SCIP_PLUGINNOTFOUND;
1272}
1273
1274/** returns the indices of the basic columns and rows; basic column n gives value n, basic row m gives value -1-m */
1276 SCIP_LPI* lpi, /**< LP interface structure */
1277 int* bind /**< pointer to store basis indices ready to keep number of rows entries */
1278 )
1279{ /*lint --e{715}*/
1280 assert(lpi != NULL);
1281 assert(bind != NULL);
1282 errorMessage();
1283 return SCIP_PLUGINNOTFOUND;
1284}
1285
1286/** get row of inverse basis matrix B^-1
1287 *
1288 * @note The LP interface defines slack variables to have coefficient +1. This means that if, internally, the LP solver
1289 * uses a -1 coefficient, then rows associated with slacks variables whose coefficient is -1, should be negated;
1290 * see also the explanation in lpi.h.
1291 */
1293 SCIP_LPI* lpi, /**< LP interface structure */
1294 int r, /**< row number */
1295 SCIP_Real* coef, /**< pointer to store the coefficients of the row */
1296 int* inds, /**< array to store the non-zero indices, or NULL */
1297 int* ninds /**< pointer to store the number of non-zero indices, or NULL
1298 * (-1: if we do not store sparsity information) */
1299 )
1300{ /*lint --e{715}*/
1301 assert(lpi != NULL);
1302 assert(coef != NULL);
1303 errorMessage();
1304 return SCIP_PLUGINNOTFOUND;
1305}
1306
1307/** get column of inverse basis matrix B^-1
1308 *
1309 * @note The LP interface defines slack variables to have coefficient +1. This means that if, internally, the LP solver
1310 * uses a -1 coefficient, then rows associated with slacks variables whose coefficient is -1, should be negated;
1311 * see also the explanation in lpi.h.
1312 */
1314 SCIP_LPI* lpi, /**< LP interface structure */
1315 int c, /**< column number of B^-1; this is NOT the number of the column in the LP;
1316 * you have to call SCIPlpiGetBasisInd() to get the array which links the
1317 * B^-1 column numbers to the row and column numbers of the LP!
1318 * c must be between 0 and nrows-1, since the basis has the size
1319 * nrows * nrows */
1320 SCIP_Real* coef, /**< pointer to store the coefficients of the column */
1321 int* inds, /**< array to store the non-zero indices, or NULL */
1322 int* ninds /**< pointer to store the number of non-zero indices, or NULL
1323 * (-1: if we do not store sparsity information) */
1324 )
1325{ /*lint --e{715}*/
1326 assert(lpi != NULL);
1327 assert(coef != NULL);
1328 errorMessage();
1329 return SCIP_PLUGINNOTFOUND;
1330}
1331
1332/** get row of inverse basis matrix times constraint matrix B^-1 * A
1333 *
1334 * @note The LP interface defines slack variables to have coefficient +1. This means that if, internally, the LP solver
1335 * uses a -1 coefficient, then rows associated with slacks variables whose coefficient is -1, should be negated;
1336 * see also the explanation in lpi.h.
1337 */
1339 SCIP_LPI* lpi, /**< LP interface structure */
1340 int r, /**< row number */
1341 const SCIP_Real* binvrow, /**< row in (A_B)^-1 from prior call to SCIPlpiGetBInvRow(), or NULL */
1342 SCIP_Real* coef, /**< vector to return coefficients of the row */
1343 int* inds, /**< array to store the non-zero indices, or NULL */
1344 int* ninds /**< pointer to store the number of non-zero indices, or NULL
1345 * (-1: if we do not store sparsity information) */
1346 )
1347{ /*lint --e{715}*/
1348 assert(lpi != NULL);
1349 assert(coef != NULL);
1350 errorMessage();
1351 return SCIP_PLUGINNOTFOUND;
1352}
1353
1354/** get column of inverse basis matrix times constraint matrix B^-1 * A
1355 *
1356 * @note The LP interface defines slack variables to have coefficient +1. This means that if, internally, the LP solver
1357 * uses a -1 coefficient, then rows associated with slacks variables whose coefficient is -1, should be negated;
1358 * see also the explanation in lpi.h.
1359 */
1361 SCIP_LPI* lpi, /**< LP interface structure */
1362 int c, /**< column number */
1363 SCIP_Real* coef, /**< vector to return coefficients of the column */
1364 int* inds, /**< array to store the non-zero indices, or NULL */
1365 int* ninds /**< pointer to store the number of non-zero indices, or NULL
1366 * (-1: if we do not store sparsity information) */
1367 )
1368{ /*lint --e{715}*/
1369 assert(lpi != NULL);
1370 assert(coef != NULL);
1371 errorMessage();
1372 return SCIP_PLUGINNOTFOUND;
1373}
1374
1375/**@} */
1376
1377
1378
1379
1380/*
1381 * LP State Methods
1382 */
1383
1384/**@name LP State Methods */
1385/**@{ */
1386
1387/** stores LPi state (like basis information) into lpistate object */
1389 SCIP_LPI* lpi, /**< LP interface structure */
1390 BMS_BLKMEM* blkmem, /**< block memory */
1391 SCIP_LPISTATE** lpistate /**< pointer to LPi state information (like basis information) */
1392 )
1393{ /*lint --e{715}*/
1394 assert(lpi != NULL);
1395 assert(blkmem != NULL);
1396 assert(lpistate != NULL);
1397 assert(blkmem != NULL);
1398 errorMessage();
1399 return SCIP_PLUGINNOTFOUND;
1400}
1401
1402/** loads LPi state (like basis information) into solver; note that the LP might have been extended with additional
1403 * columns and rows since the state was stored with SCIPlpiGetState()
1404 */
1406 SCIP_LPI* lpi, /**< LP interface structure */
1407 BMS_BLKMEM* blkmem, /**< block memory */
1408 const SCIP_LPISTATE* lpistate /**< LPi state information (like basis information), or NULL */
1409 )
1410{ /*lint --e{715}*/
1411 assert(lpi != NULL);
1412 assert(blkmem != NULL);
1413 assert(lpistate != NULL);
1414 errorMessage();
1415 return SCIP_PLUGINNOTFOUND;
1416}
1417
1418/** clears current LPi state (like basis information) of the solver */
1420 SCIP_LPI* lpi /**< LP interface structure */
1421 )
1422{ /*lint --e{715}*/
1423 assert(lpi != NULL);
1424 return SCIP_OKAY;
1425}
1426
1427/** frees LPi state information */
1429 SCIP_LPI* lpi, /**< LP interface structure */
1430 BMS_BLKMEM* blkmem, /**< block memory */
1431 SCIP_LPISTATE** lpistate /**< pointer to LPi state information (like basis information) */
1432 )
1433{ /*lint --e{715}*/
1434 assert(lpi != NULL);
1435 assert(lpistate != NULL);
1436 assert(blkmem != NULL);
1437 return SCIP_OKAY;
1438}
1439
1440/** checks, whether the given LP state contains simplex basis information */
1442 SCIP_LPI* lpi, /**< LP interface structure */
1443 SCIP_LPISTATE* lpistate /**< LP state information (like basis information), or NULL */
1444 )
1445{ /*lint --e{715}*/
1446 assert(lpi != NULL);
1448 return FALSE;
1449}
1450
1451/** reads LP state (like basis information from a file */
1453 SCIP_LPI* lpi, /**< LP interface structure */
1454 const char* fname /**< file name */
1455 )
1456{ /*lint --e{715}*/
1457 assert(lpi != NULL);
1458 assert(fname != NULL);
1459 errorMessage();
1460 return SCIP_PLUGINNOTFOUND;
1461}
1462
1463/** writes LPi state (i.e. basis information) to a file */
1465 SCIP_LPI* lpi, /**< LP interface structure */
1466 const char* fname /**< file name */
1467 )
1468{ /*lint --e{715}*/
1469 assert(lpi != NULL);
1470 assert(fname != NULL);
1471 errorMessage();
1472 return SCIP_PLUGINNOTFOUND;
1473}
1474
1475/**@} */
1476
1477
1478
1479
1480/*
1481 * LP Pricing Norms Methods
1482 */
1483
1484/**@name LP Pricing Norms Methods */
1485/**@{ */
1486
1487/** stores LPi pricing norms information
1488 * @todo should we store norm information?
1489 */
1491 SCIP_LPI* lpi, /**< LP interface structure */
1492 BMS_BLKMEM* blkmem, /**< block memory */
1493 SCIP_LPINORMS** lpinorms /**< pointer to LPi pricing norms information */
1494 )
1495{ /*lint --e{715}*/
1496 assert(lpi != NULL);
1497 assert(blkmem != NULL);
1498 assert(lpinorms != NULL);
1499 errorMessage();
1500 return SCIP_PLUGINNOTFOUND;
1501}
1502
1503/** loads LPi pricing norms into solver; note that the LP might have been extended with additional
1504 * columns and rows since the state was stored with SCIPlpiGetNorms()
1505 */
1507 SCIP_LPI* lpi, /**< LP interface structure */
1508 BMS_BLKMEM* blkmem, /**< block memory */
1509 const SCIP_LPINORMS* lpinorms /**< LPi pricing norms information, or NULL */
1510 )
1511{ /*lint --e{715}*/
1512 assert(lpi != NULL);
1513 errorMessage();
1514 return SCIP_PLUGINNOTFOUND;
1515}
1516
1517/** frees pricing norms information */
1519 SCIP_LPI* lpi, /**< LP interface structure */
1520 BMS_BLKMEM* blkmem, /**< block memory */
1521 SCIP_LPINORMS** lpinorms /**< pointer to LPi pricing norms information, or NULL */
1522 )
1523{ /*lint --e{715}*/
1524 assert(lpi != NULL);
1525 errorMessage();
1526 return SCIP_PLUGINNOTFOUND;
1527}
1528
1529/**@} */
1530
1531
1532
1533
1534/*
1535 * Parameter Methods
1536 */
1537
1538/**@name Parameter Methods */
1539/**@{ */
1540
1541/** gets integer parameter of LP */
1543 SCIP_LPI* lpi, /**< LP interface structure */
1544 SCIP_LPPARAM type, /**< parameter number */
1545 int* ival /**< buffer to store the parameter value */
1546 )
1547{ /*lint --e{715}*/
1548 assert(lpi != NULL);
1549 assert(ival != NULL);
1550 return SCIP_PARAMETERUNKNOWN;
1551}
1552
1553/** sets integer parameter of LP */
1555 SCIP_LPI* lpi, /**< LP interface structure */
1556 SCIP_LPPARAM type, /**< parameter number */
1557 int ival /**< parameter value */
1558 )
1559{ /*lint --e{715}*/
1560 assert(lpi != NULL);
1561 return SCIP_PARAMETERUNKNOWN;
1562}
1563
1564/** gets floating point parameter of LP */
1566 SCIP_LPI* lpi, /**< LP interface structure */
1567 SCIP_LPPARAM type, /**< parameter number */
1568 SCIP_Real* dval /**< buffer to store the parameter value */
1569 )
1570{ /*lint --e{715}*/
1571 assert(lpi != NULL);
1572 assert(dval != NULL);
1573 return SCIP_PARAMETERUNKNOWN;
1574}
1575
1576/** sets floating point parameter of LP */
1578 SCIP_LPI* lpi, /**< LP interface structure */
1579 SCIP_LPPARAM type, /**< parameter number */
1580 SCIP_Real dval /**< parameter value */
1581 )
1582{ /*lint --e{715}*/
1583 assert(lpi != NULL);
1584 return SCIP_PARAMETERUNKNOWN;
1585}
1586
1587/** interrupts the currently ongoing lp solve or disables the interrupt */
1589 SCIP_LPI* lpi, /**< LP interface structure */
1590 SCIP_Bool interrupt /**< TRUE if interrupt should be set, FALSE if it should be disabled */
1591 )
1592{
1593 /*lint --e{715}*/
1594 assert(lpi != NULL);
1595
1596 return SCIP_OKAY;
1597}
1598
1599/**@} */
1600
1601/*
1602 * Numerical Methods
1603 */
1604
1605/**@name Numerical Methods */
1606/**@{ */
1607
1608/** returns value treated as infinity in the LP solver */
1610 SCIP_LPI* lpi /**< LP interface structure */
1611 )
1612{ /*lint --e{715}*/
1613 assert(lpi != NULL);
1614 return LPIINFINITY;
1615}
1616
1617/** checks if given value is treated as infinity in the LP solver */
1619 SCIP_LPI* lpi, /**< LP interface structure */
1620 SCIP_Real val /**< value to be checked for infinity */
1621 )
1622{ /*lint --e{715}*/
1623 assert(lpi != NULL);
1624 if( val >= LPIINFINITY )
1625 return TRUE;
1626 return FALSE;
1627}
1628
1629/**@} */
1630
1631
1632
1633
1634/*
1635 * File Interface Methods
1636 */
1637
1638/**@name File Interface Methods */
1639/**@{ */
1640
1641/** reads LP from a file */
1643 SCIP_LPI* lpi, /**< LP interface structure */
1644 const char* fname /**< file name */
1645 )
1646{ /*lint --e{715}*/
1647 assert(lpi != NULL);
1648 assert(fname != NULL);
1649 errorMessage();
1650 return SCIP_PLUGINNOTFOUND;
1651}
1652
1653/** writes LP to a file */
1655 SCIP_LPI* lpi, /**< LP interface structure */
1656 const char* fname /**< file name */
1657 )
1658{ /*lint --e{715}*/
1659 assert(lpi != NULL);
1660 errorMessage();
1661 return SCIP_PLUGINNOTFOUND;
1662}
1663
1664/**@} */
SCIP_Real * r
Definition: circlepacking.c:59
#define NULL
Definition: def.h:266
#define SCIP_INVALID
Definition: def.h:192
#define SCIP_Bool
Definition: def.h:91
#define SCIP_ALLOC(x)
Definition: def.h:384
#define SCIP_Real
Definition: def.h:172
#define TRUE
Definition: def.h:93
#define FALSE
Definition: def.h:94
#define SCIPABORT()
Definition: def.h:345
SCIP_RETCODE SCIPlpiChgSides(SCIP_LPI *lpi, int nrows, const int *ind, const SCIP_Real *lhs, const SCIP_Real *rhs)
Definition: lpi_none.c:479
SCIP_RETCODE SCIPlpiSetState(SCIP_LPI *lpi, BMS_BLKMEM *blkmem, const SCIP_LPISTATE *lpistate)
Definition: lpi_none.c:1405
SCIP_RETCODE SCIPlpiGetBInvACol(SCIP_LPI *lpi, int c, SCIP_Real *coef, int *inds, int *ninds)
Definition: lpi_none.c:1360
SCIP_RETCODE SCIPlpiGetRealpar(SCIP_LPI *lpi, SCIP_LPPARAM type, SCIP_Real *dval)
Definition: lpi_none.c:1565
SCIP_Real SCIPlpiInfinity(SCIP_LPI *lpi)
Definition: lpi_none.c:1609
SCIP_Bool SCIPlpiIsObjlimExc(SCIP_LPI *lpi)
Definition: lpi_none.c:1099
SCIP_RETCODE SCIPlpiChgObjsen(SCIP_LPI *lpi, SCIP_OBJSEN objsen)
Definition: lpi_none.c:507
SCIP_Bool SCIPlpiIsInfinity(SCIP_LPI *lpi, SCIP_Real val)
Definition: lpi_none.c:1618
SCIP_RETCODE SCIPlpiClear(SCIP_LPI *lpi)
Definition: lpi_none.c:431
SCIP_RETCODE SCIPlpiClearState(SCIP_LPI *lpi)
Definition: lpi_none.c:1419
SCIP_Bool SCIPlpiExistsDualRay(SCIP_LPI *lpi)
Definition: lpi_none.c:1021
SCIP_Bool SCIPlpiExistsPrimalRay(SCIP_LPI *lpi)
Definition: lpi_none.c:967
SCIP_RETCODE SCIPlpiGetBase(SCIP_LPI *lpi, int *cstat, int *rstat)
Definition: lpi_none.c:1249
SCIP_RETCODE SCIPlpiReadState(SCIP_LPI *lpi, const char *fname)
Definition: lpi_none.c:1452
SCIP_RETCODE SCIPlpiAddRows(SCIP_LPI *lpi, int nrows, const SCIP_Real *lhs, const SCIP_Real *rhs, char **rownames, int nnonz, const int *beg, const int *ind, const SCIP_Real *val)
Definition: lpi_none.c:346
SCIP_RETCODE SCIPlpiGetPrimalRay(SCIP_LPI *lpi, SCIP_Real *ray)
Definition: lpi_none.c:1182
SCIP_RETCODE SCIPlpiGetIntpar(SCIP_LPI *lpi, SCIP_LPPARAM type, int *ival)
Definition: lpi_none.c:1542
SCIP_RETCODE SCIPlpiWriteLP(SCIP_LPI *lpi, const char *fname)
Definition: lpi_none.c:1654
SCIP_RETCODE SCIPlpiSetIntegralityInformation(SCIP_LPI *lpi, int ncols, int *intInfo)
Definition: lpi_none.c:119
SCIP_Bool SCIPlpiIsDualInfeasible(SCIP_LPI *lpi)
Definition: lpi_none.c:1053
SCIP_RETCODE SCIPlpiSetRealpar(SCIP_LPI *lpi, SCIP_LPPARAM type, SCIP_Real dval)
Definition: lpi_none.c:1577
SCIP_RETCODE SCIPlpiStrongbranchFrac(SCIP_LPI *lpi, int col, SCIP_Real psol, int itlim, SCIP_Real *down, SCIP_Real *up, SCIP_Bool *downvalid, SCIP_Bool *upvalid, int *iter)
Definition: lpi_none.c:819
SCIP_RETCODE SCIPlpiSetNorms(SCIP_LPI *lpi, BMS_BLKMEM *blkmem, const SCIP_LPINORMS *lpinorms)
Definition: lpi_none.c:1506
SCIP_RETCODE SCIPlpiGetNNonz(SCIP_LPI *lpi, int *nnonz)
Definition: lpi_none.c:597
SCIP_Bool SCIPlpiHasPrimalSolve(void)
Definition: lpi_none.c:130
SCIP_RETCODE SCIPlpiStrongbranchInt(SCIP_LPI *lpi, int col, SCIP_Real psol, int itlim, SCIP_Real *down, SCIP_Real *up, SCIP_Bool *downvalid, SCIP_Bool *upvalid, int *iter)
Definition: lpi_none.c:870
SCIP_RETCODE SCIPlpiGetBounds(SCIP_LPI *lpi, int firstcol, int lastcol, SCIP_Real *lbs, SCIP_Real *ubs)
Definition: lpi_none.c:714
SCIP_Bool SCIPlpiHasBarrierSolve(void)
Definition: lpi_none.c:146
SCIP_RETCODE SCIPlpiGetDualfarkas(SCIP_LPI *lpi, SCIP_Real *dualfarkas)
Definition: lpi_none.c:1194
SCIP_RETCODE SCIPlpiGetObjval(SCIP_LPI *lpi, SCIP_Real *objval)
Definition: lpi_none.c:1151
SCIP_RETCODE SCIPlpiScaleCol(SCIP_LPI *lpi, int col, SCIP_Real scaleval)
Definition: lpi_none.c:544
int SCIPlpiGetInternalStatus(SCIP_LPI *lpi)
Definition: lpi_none.c:1129
SCIP_RETCODE SCIPlpiStartStrongbranch(SCIP_LPI *lpi)
Definition: lpi_none.c:801
SCIP_RETCODE SCIPlpiGetSolFeasibility(SCIP_LPI *lpi, SCIP_Bool *primalfeasible, SCIP_Bool *dualfeasible)
Definition: lpi_none.c:951
SCIP_RETCODE SCIPlpiFreeNorms(SCIP_LPI *lpi, BMS_BLKMEM *blkmem, SCIP_LPINORMS **lpinorms)
Definition: lpi_none.c:1518
SCIP_Bool SCIPlpiIsIterlimExc(SCIP_LPI *lpi)
Definition: lpi_none.c:1109
SCIP_RETCODE SCIPlpiChgBounds(SCIP_LPI *lpi, int ncols, const int *ind, const SCIP_Real *lb, const SCIP_Real *ub)
Definition: lpi_none.c:446
SCIP_Bool SCIPlpiIsPrimalUnbounded(SCIP_LPI *lpi)
Definition: lpi_none.c:989
SCIP_RETCODE SCIPlpiIgnoreInstability(SCIP_LPI *lpi, SCIP_Bool *success)
Definition: lpi_none.c:1139
SCIP_RETCODE SCIPlpiWriteState(SCIP_LPI *lpi, const char *fname)
Definition: lpi_none.c:1464
SCIP_RETCODE SCIPlpiFree(SCIP_LPI **lpi)
Definition: lpi_none.c:187
SCIP_RETCODE SCIPlpiStrongbranchesFrac(SCIP_LPI *lpi, int *cols, int ncols, SCIP_Real *psols, int itlim, SCIP_Real *down, SCIP_Real *up, SCIP_Bool *downvalid, SCIP_Bool *upvalid, int *iter)
Definition: lpi_none.c:843
SCIP_RETCODE SCIPlpiGetCoef(SCIP_LPI *lpi, int row, int col, SCIP_Real *val)
Definition: lpi_none.c:744
SCIP_Bool SCIPlpiIsPrimalFeasible(SCIP_LPI *lpi)
Definition: lpi_none.c:1009
SCIP_RETCODE SCIPlpiReadLP(SCIP_LPI *lpi, const char *fname)
Definition: lpi_none.c:1642
SCIP_RETCODE SCIPlpiGetRealSolQuality(SCIP_LPI *lpi, SCIP_LPSOLQUALITY qualityindicator, SCIP_Real *quality)
Definition: lpi_none.c:1222
SCIP_Bool SCIPlpiIsDualFeasible(SCIP_LPI *lpi)
Definition: lpi_none.c:1063
SCIP_RETCODE SCIPlpiGetNorms(SCIP_LPI *lpi, BMS_BLKMEM *blkmem, SCIP_LPINORMS **lpinorms)
Definition: lpi_none.c:1490
SCIP_Bool SCIPlpiIsTimelimExc(SCIP_LPI *lpi)
Definition: lpi_none.c:1119
SCIP_Bool SCIPlpiHasStateBasis(SCIP_LPI *lpi, SCIP_LPISTATE *lpistate)
Definition: lpi_none.c:1441
SCIP_RETCODE SCIPlpiSetIntpar(SCIP_LPI *lpi, SCIP_LPPARAM type, int ival)
Definition: lpi_none.c:1554
const char * SCIPlpiGetSolverName(void)
Definition: lpi_none.c:95
SCIP_RETCODE SCIPlpiSetBase(SCIP_LPI *lpi, const int *cstat, const int *rstat)
Definition: lpi_none.c:1261
SCIP_Bool SCIPlpiHasPrimalRay(SCIP_LPI *lpi)
Definition: lpi_none.c:979
SCIP_RETCODE SCIPlpiGetBInvRow(SCIP_LPI *lpi, int r, SCIP_Real *coef, int *inds, int *ninds)
Definition: lpi_none.c:1292
SCIP_RETCODE SCIPlpiDelRows(SCIP_LPI *lpi, int firstrow, int lastrow)
Definition: lpi_none.c:384
SCIP_RETCODE SCIPlpiGetCols(SCIP_LPI *lpi, int firstcol, int lastcol, SCIP_Real *lb, SCIP_Real *ub, int *nnonz, int *beg, int *ind, SCIP_Real *val)
Definition: lpi_none.c:612
SCIP_RETCODE SCIPlpiGetBInvCol(SCIP_LPI *lpi, int c, SCIP_Real *coef, int *inds, int *ninds)
Definition: lpi_none.c:1313
SCIP_RETCODE SCIPlpiGetColNames(SCIP_LPI *lpi, int firstcol, int lastcol, char **colnames, char *namestorage, int namestoragesize, int *storageleft)
Definition: lpi_none.c:649
SCIP_RETCODE SCIPlpiGetBInvARow(SCIP_LPI *lpi, int r, const SCIP_Real *binvrow, SCIP_Real *coef, int *inds, int *ninds)
Definition: lpi_none.c:1338
SCIP_RETCODE SCIPlpiGetRows(SCIP_LPI *lpi, int firstrow, int lastrow, SCIP_Real *lhs, SCIP_Real *rhs, int *nnonz, int *beg, int *ind, SCIP_Real *val)
Definition: lpi_none.c:632
SCIP_Bool SCIPlpiWasSolved(SCIP_LPI *lpi)
Definition: lpi_none.c:932
const char * SCIPlpiGetSolverDesc(void)
Definition: lpi_none.c:103
SCIP_RETCODE SCIPlpiSolveBarrier(SCIP_LPI *lpi, SCIP_Bool crossover)
Definition: lpi_none.c:790
SCIP_Bool SCIPlpiIsOptimal(SCIP_LPI *lpi)
Definition: lpi_none.c:1073
SCIP_RETCODE SCIPlpiGetRowNames(SCIP_LPI *lpi, int firstrow, int lastrow, char **rownames, char *namestorage, int namestoragesize, int *storageleft)
Definition: lpi_none.c:669
SCIP_Bool SCIPlpiHasDualSolve(void)
Definition: lpi_none.c:138
SCIP_RETCODE SCIPlpiEndStrongbranch(SCIP_LPI *lpi)
Definition: lpi_none.c:810
SCIP_RETCODE SCIPlpiGetSides(SCIP_LPI *lpi, int firstrow, int lastrow, SCIP_Real *lhss, SCIP_Real *rhss)
Definition: lpi_none.c:729
SCIP_RETCODE SCIPlpiStrongbranchesInt(SCIP_LPI *lpi, int *cols, int ncols, SCIP_Real *psols, int itlim, SCIP_Real *down, SCIP_Real *up, SCIP_Bool *downvalid, SCIP_Bool *upvalid, int *iter)
Definition: lpi_none.c:894
SCIP_RETCODE SCIPlpiGetSol(SCIP_LPI *lpi, SCIP_Real *objval, SCIP_Real *primsol, SCIP_Real *dualsol, SCIP_Real *activity, SCIP_Real *redcost)
Definition: lpi_none.c:1167
SCIP_Bool SCIPlpiHasDualRay(SCIP_LPI *lpi)
Definition: lpi_none.c:1033
SCIP_RETCODE SCIPlpiDelColset(SCIP_LPI *lpi, int *dstat)
Definition: lpi_none.c:315
SCIP_RETCODE SCIPlpiGetObj(SCIP_LPI *lpi, int firstcol, int lastcol, SCIP_Real *vals)
Definition: lpi_none.c:699
SCIP_RETCODE SCIPlpiFreeState(SCIP_LPI *lpi, BMS_BLKMEM *blkmem, SCIP_LPISTATE **lpistate)
Definition: lpi_none.c:1428
SCIP_Bool SCIPlpiIsPrimalInfeasible(SCIP_LPI *lpi)
Definition: lpi_none.c:999
SCIP_RETCODE SCIPlpiSolveDual(SCIP_LPI *lpi)
Definition: lpi_none.c:780
SCIP_RETCODE SCIPlpiAddCols(SCIP_LPI *lpi, int ncols, const SCIP_Real *obj, const SCIP_Real *lb, const SCIP_Real *ub, char **colnames, int nnonz, const int *beg, const int *ind, const SCIP_Real *val)
Definition: lpi_none.c:257
SCIP_RETCODE SCIPlpiSolvePrimal(SCIP_LPI *lpi)
Definition: lpi_none.c:770
SCIP_RETCODE SCIPlpiLoadColLP(SCIP_LPI *lpi, SCIP_OBJSEN objsen, int ncols, const SCIP_Real *obj, const SCIP_Real *lb, const SCIP_Real *ub, char **colnames, int nrows, const SCIP_Real *lhs, const SCIP_Real *rhs, char **rownames, int nnonz, const int *beg, const int *ind, const SCIP_Real *val)
Definition: lpi_none.c:212
SCIP_Bool SCIPlpiIsDualUnbounded(SCIP_LPI *lpi)
Definition: lpi_none.c:1043
SCIP_RETCODE SCIPlpiGetIterations(SCIP_LPI *lpi, int *iterations)
Definition: lpi_none.c:1206
SCIP_RETCODE SCIPlpiGetBasisInd(SCIP_LPI *lpi, int *bind)
Definition: lpi_none.c:1275
SCIP_RETCODE SCIPlpiCreate(SCIP_LPI **lpi, SCIP_MESSAGEHDLR *messagehdlr, const char *name, SCIP_OBJSEN objsen)
Definition: lpi_none.c:166
void * SCIPlpiGetSolverPointer(SCIP_LPI *lpi)
Definition: lpi_none.c:111
SCIP_RETCODE SCIPlpiChgObj(SCIP_LPI *lpi, int ncols, const int *ind, const SCIP_Real *obj)
Definition: lpi_none.c:517
SCIP_RETCODE SCIPlpiGetObjsen(SCIP_LPI *lpi, SCIP_OBJSEN *objsen)
Definition: lpi_none.c:689
SCIP_Bool SCIPlpiIsStable(SCIP_LPI *lpi)
Definition: lpi_none.c:1089
SCIP_RETCODE SCIPlpiGetNCols(SCIP_LPI *lpi, int *ncols)
Definition: lpi_none.c:582
SCIP_RETCODE SCIPlpiInterrupt(SCIP_LPI *lpi, SCIP_Bool interrupt)
Definition: lpi_none.c:1588
SCIP_RETCODE SCIPlpiDelCols(SCIP_LPI *lpi, int firstcol, int lastcol)
Definition: lpi_none.c:299
SCIP_RETCODE SCIPlpiDelRowset(SCIP_LPI *lpi, int *dstat)
Definition: lpi_none.c:400
SCIP_RETCODE SCIPlpiScaleRow(SCIP_LPI *lpi, int row, SCIP_Real scaleval)
Definition: lpi_none.c:531
SCIP_RETCODE SCIPlpiGetNRows(SCIP_LPI *lpi, int *nrows)
Definition: lpi_none.c:567
SCIP_RETCODE SCIPlpiGetState(SCIP_LPI *lpi, BMS_BLKMEM *blkmem, SCIP_LPISTATE **lpistate)
Definition: lpi_none.c:1388
SCIP_RETCODE SCIPlpiChgCoef(SCIP_LPI *lpi, int row, int col, SCIP_Real newval)
Definition: lpi_none.c:495
interface methods for specific LP solvers
static void errorMessage(void)
Definition: lpi_none.c:74
#define LPINAME
Definition: lpi_none.c:38
static void errorMessageAbort(void)
Definition: lpi_none.c:63
#define LPIINFINITY
Definition: lpi_none.c:39
#define BMSfreeMemory(ptr)
Definition: memory.h:145
struct BMS_BlkMem BMS_BLKMEM
Definition: memory.h:437
#define BMSallocMemory(ptr)
Definition: memory.h:118
public methods for message output
#define SCIPerrorMessage
Definition: pub_message.h:64
#define SCIPdebugMessage
Definition: pub_message.h:96
int ncols
Definition: lpi_none.c:53
int nrows
Definition: lpi_none.c:52
enum SCIP_LPParam SCIP_LPPARAM
Definition: type_lpi.h:73
enum SCIP_LPSolQuality SCIP_LPSOLQUALITY
Definition: type_lpi.h:104
enum SCIP_ObjSen SCIP_OBJSEN
Definition: type_lpi.h:45
@ SCIP_LPERROR
Definition: type_retcode.h:49
@ SCIP_PLUGINNOTFOUND
Definition: type_retcode.h:54
@ SCIP_PARAMETERUNKNOWN
Definition: type_retcode.h:55
@ SCIP_OKAY
Definition: type_retcode.h:42
enum SCIP_Retcode SCIP_RETCODE
Definition: type_retcode.h:63