Scippy

SCIP

Solving Constraint Integer Programs

scip_tree.h
Go to the documentation of this file.
1 /* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */
2 /* */
3 /* This file is part of the program and library */
4 /* SCIP --- Solving Constraint Integer Programs */
5 /* */
6 /* Copyright (c) 2002-2023 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 scip_tree.h
26  * @ingroup PUBLICCOREAPI
27  * @brief public methods for the branch-and-bound tree
28  * @author Tobias Achterberg
29  * @author Timo Berthold
30  * @author Thorsten Koch
31  * @author Alexander Martin
32  * @author Marc Pfetsch
33  * @author Kati Wolter
34  * @author Gregor Hendel
35  * @author Leona Gottwald
36  */
37 
38 /*---+----1----+----2----+----3----+----4----+----5----+----6----+----7----+----8----+----9----+----0----+----1----+----2*/
39 
40 #ifndef __SCIP_SCIP_TREE_H__
41 #define __SCIP_SCIP_TREE_H__
42 
43 
44 #include "scip/def.h"
45 #include "scip/type_retcode.h"
46 #include "scip/type_scip.h"
47 #include "scip/type_tree.h"
48 
49 #ifdef __cplusplus
50 extern "C" {
51 #endif
52 
53 /**@addtogroup PublicTreeMethods
54  *
55  * @{
56  */
57 
58 /** gets focus node in the tree
59  *
60  * if we are in probing/diving mode this method returns the node in the tree where the probing/diving mode was started.
61  *
62  * @return the current node of the search tree
63  *
64  * @pre This method can be called if @p scip is in one of the following stages:
65  * - \ref SCIP_STAGE_INITPRESOLVE
66  * - \ref SCIP_STAGE_PRESOLVING
67  * - \ref SCIP_STAGE_EXITPRESOLVE
68  * - \ref SCIP_STAGE_SOLVING
69  */
70 SCIP_EXPORT
72  SCIP* scip /**< SCIP data structure */
73  );
74 
75 /** gets current node in the tree
76  *
77  * @return the current node of the search tree
78  *
79  * @pre This method can be called if @p scip is in one of the following stages:
80  * - \ref SCIP_STAGE_INITPRESOLVE
81  * - \ref SCIP_STAGE_PRESOLVING
82  * - \ref SCIP_STAGE_EXITPRESOLVE
83  * - \ref SCIP_STAGE_SOLVING
84  */
85 SCIP_EXPORT
87  SCIP* scip /**< SCIP data structure */
88  );
89 
90 /** gets depth of current node, or -1 if no current node exists; in probing, the current node is the last probing node,
91  * such that the depth includes the probing path
92  *
93  * @return the depth of current node, or -1 if no current node exists; in probing, the current node is the last probing node,
94  * such that the depth includes the probing path
95  *
96  * @pre This method can be called if SCIP is in one of the following stages:
97  * - \ref SCIP_STAGE_TRANSFORMED
98  * - \ref SCIP_STAGE_INITPRESOLVE
99  * - \ref SCIP_STAGE_PRESOLVING
100  * - \ref SCIP_STAGE_EXITPRESOLVE
101  * - \ref SCIP_STAGE_PRESOLVED
102  * - \ref SCIP_STAGE_INITSOLVE
103  * - \ref SCIP_STAGE_SOLVING
104  * - \ref SCIP_STAGE_SOLVED
105  * - \ref SCIP_STAGE_EXITSOLVE
106  */
107 SCIP_EXPORT
108 int SCIPgetDepth(
109  SCIP* scip /**< SCIP data structure */
110  );
111 
112 /** gets depth of the focus node, or -1 if no focus node exists; the focus node is the currently processed node in the
113  * branching tree, excluding the nodes of the probing path
114  *
115  * @return the depth of the focus node, or -1 if no focus node exists; the focus node is the currently processed node in the
116  * branching tree, excluding the nodes of the probing path
117  *
118  * @pre This method can be called if SCIP is in one of the following stages:
119  * - \ref SCIP_STAGE_TRANSFORMED
120  * - \ref SCIP_STAGE_INITPRESOLVE
121  * - \ref SCIP_STAGE_PRESOLVING
122  * - \ref SCIP_STAGE_EXITPRESOLVE
123  * - \ref SCIP_STAGE_PRESOLVED
124  * - \ref SCIP_STAGE_INITSOLVE
125  * - \ref SCIP_STAGE_SOLVING
126  * - \ref SCIP_STAGE_SOLVED
127  * - \ref SCIP_STAGE_EXITSOLVE
128  */
129 SCIP_EXPORT
131  SCIP* scip /**< SCIP data structure */
132  );
133 
134 /** gets current plunging depth (successive times, a child was selected as next node)
135  *
136  * @return the current plunging depth (successive times, a child was selected as next node)
137  *
138  * @pre This method can be called if SCIP is in one of the following stages:
139  * - \ref SCIP_STAGE_PRESOLVED
140  * - \ref SCIP_STAGE_SOLVING
141  */
142 SCIP_EXPORT
144  SCIP* scip /**< SCIP data structure */
145  );
146 
147 /** gets the root node of the tree
148  *
149  * @return the root node of the search tree
150  *
151  * @pre This method can be called if @p scip is in one of the following stages:
152  * - \ref SCIP_STAGE_INITPRESOLVE
153  * - \ref SCIP_STAGE_PRESOLVING
154  * - \ref SCIP_STAGE_EXITPRESOLVE
155  * - \ref SCIP_STAGE_SOLVING
156  */
157 SCIP_EXPORT
159  SCIP* scip /**< SCIP data structure */
160  );
161 
162 /** gets the effective root depth, i.e., the depth of the deepest node which is part of all paths from the root node
163  * to the unprocessed nodes.
164  *
165  * @return effective root depth
166  *
167  * @pre This method can be called if @p scip is in one of the following stages:
168  * - \ref SCIP_STAGE_SOLVING
169  */
170 SCIP_EXPORT
172  SCIP* scip /**< SCIP data structure */
173  );
174 
175 /** returns whether the current node is already solved and only propagated again
176  *
177  * @return TRUE is returned if \SCIP performance repropagation, otherwise FALSE.
178  *
179  * @pre This method can be called if @p scip is in one of the following stages:
180  * - \ref SCIP_STAGE_INITPRESOLVE
181  * - \ref SCIP_STAGE_PRESOLVING
182  * - \ref SCIP_STAGE_EXITPRESOLVE
183  * - \ref SCIP_STAGE_SOLVING
184  */
185 SCIP_EXPORT
187  SCIP* scip /**< SCIP data structure */
188  );
189 
190 /** gets children of focus node along with the number of children
191  *
192  * @return \ref SCIP_OKAY is returned if everything worked. Otherwise a suitable error code is passed. See \ref
193  * SCIP_Retcode "SCIP_RETCODE" for a complete list of error codes.
194  *
195  * @pre This method can be called if @p scip is in one of the following stages:
196  * - \ref SCIP_STAGE_SOLVING
197  */
198 SCIP_EXPORT
200  SCIP* scip, /**< SCIP data structure */
201  SCIP_NODE*** children, /**< pointer to store children array, or NULL if not needed */
202  int* nchildren /**< pointer to store number of children, or NULL if not needed */
203  );
204 
205 /** gets number of children of focus node
206  *
207  * @return number of children of the focus node
208  *
209  * @pre This method can be called if @p scip is in one of the following stages:
210  * - \ref SCIP_STAGE_SOLVING
211  */
212 SCIP_EXPORT
213 int SCIPgetNChildren(
214  SCIP* scip /**< SCIP data structure */
215  );
216 
217 /** gets siblings of focus node along with the number of siblings
218  *
219  * @return \ref SCIP_OKAY is returned if everything worked. Otherwise a suitable error code is passed. See \ref
220  * SCIP_Retcode "SCIP_RETCODE" for a complete list of error codes.
221  *
222  * @pre This method can be called if @p scip is in one of the following stages:
223  * - \ref SCIP_STAGE_SOLVING
224  */
225 SCIP_EXPORT
227  SCIP* scip, /**< SCIP data structure */
228  SCIP_NODE*** siblings, /**< pointer to store siblings array, or NULL if not needed */
229  int* nsiblings /**< pointer to store number of siblings, or NULL if not needed */
230  );
231 
232 /** gets number of siblings of focus node
233  *
234  * @return the number of siblings of focus node
235  *
236  * @pre This method can be called if @p scip is in one of the following stages:
237  * - \ref SCIP_STAGE_SOLVING
238  */
239 SCIP_EXPORT
240 int SCIPgetNSiblings(
241  SCIP* scip /**< SCIP data structure */
242  );
243 
244 /** gets leaves of the tree along with the number of leaves
245  *
246  * @return \ref SCIP_OKAY is returned if everything worked. Otherwise a suitable error code is passed. See \ref
247  * SCIP_Retcode "SCIP_RETCODE" for a complete list of error codes.
248  *
249  * @pre This method can be called if @p scip is in one of the following stages:
250  * - \ref SCIP_STAGE_SOLVING
251  */
252 SCIP_EXPORT
254  SCIP* scip, /**< SCIP data structure */
255  SCIP_NODE*** leaves, /**< pointer to store leaves array, or NULL if not needed */
256  int* nleaves /**< pointer to store number of leaves, or NULL if not needed */
257  );
258 
259 /** gets number of leaves in the tree
260  *
261  * @return the number of leaves in the tree
262  *
263  * @pre This method can be called if @p scip is in one of the following stages:
264  * - \ref SCIP_STAGE_SOLVING
265  */
266 SCIP_EXPORT
267 int SCIPgetNLeaves(
268  SCIP* scip /**< SCIP data structure */
269  );
270 
271 /** gets number of nodes left in the tree (children + siblings + leaves)
272  *
273  * @return the number of nodes left in the tree (children + siblings + leaves)
274  *
275  * @pre This method can be called if SCIP is in one of the following stages:
276  * - \ref SCIP_STAGE_PRESOLVED
277  * - \ref SCIP_STAGE_SOLVING
278  * - \ref SCIP_STAGE_SOLVED
279  */
280 SCIP_EXPORT
282  SCIP* scip /**< SCIP data structure */
283  );
284 
285 /** gets the best child of the focus node w.r.t. the node selection priority assigned by the branching rule
286  *
287  * @return the best child of the focus node w.r.t. the node selection priority assigned by the branching rule
288  *
289  * @pre This method can be called if @p scip is in one of the following stages:
290  * - \ref SCIP_STAGE_SOLVING
291  */
292 SCIP_EXPORT
294  SCIP* scip /**< SCIP data structure */
295  );
296 
297 /** gets the best sibling of the focus node w.r.t. the node selection priority assigned by the branching rule
298  *
299  * @return the best sibling of the focus node w.r.t. the node selection priority assigned by the branching rule
300  *
301  * @pre This method can be called if @p scip is in one of the following stages:
302  * - \ref SCIP_STAGE_SOLVING
303  */
304 SCIP_EXPORT
306  SCIP* scip /**< SCIP data structure */
307  );
308 
309 /** gets the best child of the focus node w.r.t. the node selection strategy
310  *
311  * @return the best child of the focus node w.r.t. the node selection strategy
312  *
313  * @pre This method can be called if @p scip is in one of the following stages:
314  * - \ref SCIP_STAGE_SOLVING
315  */
316 SCIP_EXPORT
318  SCIP* scip /**< SCIP data structure */
319  );
320 
321 /** gets the best sibling of the focus node w.r.t. the node selection strategy
322  *
323  * @return the best sibling of the focus node w.r.t. the node selection strategy
324  *
325  * @pre This method can be called if @p scip is in one of the following stages:
326  * - \ref SCIP_STAGE_SOLVING
327  */
328 SCIP_EXPORT
330  SCIP* scip /**< SCIP data structure */
331  );
332 
333 /** gets the best leaf from the node queue w.r.t. the node selection strategy
334  *
335  * @return the best leaf from the node queue w.r.t. the node selection strategy
336  *
337  * @pre This method can be called if @p scip is in one of the following stages:
338  * - \ref SCIP_STAGE_SOLVING
339  */
340 SCIP_EXPORT
342  SCIP* scip /**< SCIP data structure */
343  );
344 
345 /** gets the best node from the tree (child, sibling, or leaf) w.r.t. the node selection strategy
346  *
347  * @return the best node from the tree (child, sibling, or leaf) w.r.t. the node selection strategy
348  *
349  * @pre This method can be called if @p scip is in one of the following stages:
350  * - \ref SCIP_STAGE_SOLVING
351  */
352 SCIP_EXPORT
354  SCIP* scip /**< SCIP data structure */
355  );
356 
357 /** gets the node with smallest lower bound from the tree (child, sibling, or leaf)
358  *
359  * @return the node with smallest lower bound from the tree (child, sibling, or leaf)
360  *
361  * @pre This method can be called if @p scip is in one of the following stages:
362  * - \ref SCIP_STAGE_SOLVING
363  */
364 SCIP_EXPORT
366  SCIP* scip /**< SCIP data structure */
367  );
368 
369 /** access to all data of open nodes (leaves, children, and siblings)
370  *
371  * @pre This method can be called if @p scip is in one of the following stages:
372  * - \ref SCIP_STAGE_SOLVING
373  */
374 SCIP_EXPORT
376  SCIP* scip, /**< SCIP data structure */
377  SCIP_NODE*** leaves, /**< pointer to store the leaves, or NULL if not needed */
378  SCIP_NODE*** children, /**< pointer to store the children, or NULL if not needed */
379  SCIP_NODE*** siblings, /**< pointer to store the siblings, or NULL if not needed */
380  int* nleaves, /**< pointer to store the number of leaves, or NULL */
381  int* nchildren, /**< pointer to store the number of children, or NULL */
382  int* nsiblings /**< pointer to store the number of siblings, or NULL */
383  );
384 
385 /** marks node and whole sub tree to be cut off from branch and bound tree
386  *
387  * @return \ref SCIP_OKAY is returned if everything worked. Otherwise a suitable error code is passed. See \ref
388  * SCIP_Retcode "SCIP_RETCODE" for a complete list of error codes.
389  *
390  * @pre This method can be called if @p scip is in one of the following stages:
391  * - \ref SCIP_STAGE_SOLVING
392  */
393 SCIP_EXPORT
395  SCIP* scip, /**< SCIP data structure */
396  SCIP_NODE* node /**< node that should be cut off */
397  );
398 
399 /** removes all nodes from branch and bound tree that were marked to be cut off via SCIPcutoffNode()
400  *
401  * @return \ref SCIP_OKAY is returned if everything worked. Otherwise a suitable error code is passed. See \ref
402  * SCIP_Retcode "SCIP_RETCODE" for a complete list of error codes.
403  *
404  * @pre This method can be called if @p scip is in one of the following stages:
405  * - \ref SCIP_STAGE_SOLVING
406  *
407  * @note In diving mode, the removal of nodes is delayed until diving ends.
408  */
409 SCIP_EXPORT
411  SCIP* scip /**< SCIP data structure */
412  );
413 
414 /** marks the given node to be propagated again the next time a node of its subtree is processed
415  *
416  * @return \ref SCIP_OKAY is returned if everything worked. Otherwise a suitable error code is passed. See \ref
417  * SCIP_Retcode "SCIP_RETCODE" for a complete list of error codes.
418  *
419  * @pre This method can be called if @p scip is in one of the following stages:
420  * - \ref SCIP_STAGE_SOLVING
421  */
422 SCIP_EXPORT
424  SCIP* scip, /**< SCIP data structure */
425  SCIP_NODE* node /**< node that should be propagated again */
426  );
427 
428 /** returns depth of first node in active path that is marked being cutoff
429  *
430  * @return depth of first node in active path that is marked being cutoff
431  *
432  * @pre This method can be called if @p scip is in one of the following stages:
433  * - \ref SCIP_STAGE_SOLVING
434  */
435 SCIP_EXPORT
437  SCIP* scip /**< SCIP data structure */
438  );
439 
440 /** returns depth of first node in active path that has to be propagated again
441  *
442  * @return depth of first node in active path that has to be propagated again
443  *
444  * @pre This method can be called if @p scip is in one of the following stages:
445  * - \ref SCIP_STAGE_SOLVING
446  */
447 SCIP_EXPORT
449  SCIP* scip /**< SCIP data structure */
450  );
451 
452 /** prints all branching decisions on variables from the root to the given node
453  *
454  * @return \ref SCIP_OKAY is returned if everything worked. Otherwise a suitable error code is passed. See \ref
455  * SCIP_Retcode "SCIP_RETCODE" for a complete list of error codes.
456  *
457  * @pre This method can be called if @p scip is in one of the following stages:
458  * - \ref SCIP_STAGE_SOLVING
459  */
460 SCIP_EXPORT
462  SCIP* scip, /**< SCIP data structure */
463  SCIP_NODE* node, /**< node data */
464  FILE* file /**< output file (or NULL for standard output) */
465  );
466 
467 /** sets whether the LP should be solved at the focus node
468  *
469  * @note In order to have an effect, this method needs to be called after a node is focused but before the LP is
470  * solved.
471  *
472  * @pre This method can be called if @p scip is in one of the following stages:
473  * - \ref SCIP_STAGE_SOLVING
474  */
475 SCIP_EXPORT
476 void SCIPsetFocusnodeLP(
477  SCIP* scip, /**< SCIP data structure */
478  SCIP_Bool solvelp /**< should the LP be solved? */
479  );
480 
481 
482 /** query if node was the last parent of a branching of the tree
483  *
484  * @return TRUE if node was the last parent of a branching of the tree
485  *
486  * @pre This method can be called if SCIP is in one of the following stages:
487  * - \ref SCIP_STAGE_PRESOLVED
488  * - \ref SCIP_STAGE_SOLVING
489  * - \ref SCIP_STAGE_SOLVED
490  */
491 SCIP_EXPORT
493  SCIP* scip, /**< SCIP data structure */
494  SCIP_NODE* node /**< tree node, or NULL to check focus node */
495  );
496 
497 /**@} */
498 
499 #ifdef __cplusplus
500 }
501 #endif
502 
503 #endif
int SCIPgetFocusDepth(SCIP *scip)
Definition: scip_tree.c:696
SCIP_Bool SCIPinRepropagation(SCIP *scip)
Definition: scip_tree.c:146
int SCIPgetPlungeDepth(SCIP *scip)
Definition: scip_tree.c:713
SCIP_NODE * SCIPgetCurrentNode(SCIP *scip)
Definition: scip_tree.c:91
SCIP_RETCODE SCIPpruneTree(SCIP *scip)
Definition: scip_tree.c:457
SCIP_RETCODE SCIPgetLeaves(SCIP *scip, SCIP_NODE ***leaves, int *nleaves)
Definition: scip_tree.c:248
int SCIPgetNSiblings(SCIP *scip)
Definition: scip_tree.c:230
int SCIPgetNLeaves(SCIP *scip)
Definition: scip_tree.c:272
SCIP_RETCODE SCIPgetOpenNodesData(SCIP *scip, SCIP_NODE ***leaves, SCIP_NODE ***children, SCIP_NODE ***siblings, int *nleaves, int *nchildren, int *nsiblings)
Definition: scip_tree.c:398
SCIP_Bool SCIPwasNodeLastBranchParent(SCIP *scip, SCIP_NODE *node)
Definition: scip_tree.c:731
SCIP_NODE * SCIPgetBestSibling(SCIP *scip)
Definition: scip_tree.c:336
SCIP_RETCODE SCIPcutoffNode(SCIP *scip, SCIP_NODE *node)
Definition: scip_tree.c:434
enum SCIP_Retcode SCIP_RETCODE
Definition: type_retcode.h:63
int SCIPgetNNodesLeft(SCIP *scip)
Definition: scip_tree.c:644
type definitions for return codes for SCIP methods
SCIP_NODE * SCIPgetRootNode(SCIP *scip)
Definition: scip_tree.c:110
SCIP_RETCODE SCIPgetSiblings(SCIP *scip, SCIP_NODE ***siblings, int *nsiblings)
Definition: scip_tree.c:206
SCIP_RETCODE SCIPrepropagateNode(SCIP *scip, SCIP_NODE *node)
Definition: scip_tree.c:477
int SCIPgetCutoffdepth(SCIP *scip)
Definition: scip_tree.c:496
SCIP_RETCODE SCIPgetChildren(SCIP *scip, SCIP_NODE ***children, int *nchildren)
Definition: scip_tree.c:164
type definitions for SCIP&#39;s main datastructure
int SCIPgetNChildren(SCIP *scip)
Definition: scip_tree.c:188
int SCIPgetEffectiveRootDepth(SCIP *scip)
Definition: scip_tree.c:127
SCIP_NODE * SCIPgetBestboundNode(SCIP *scip)
Definition: scip_tree.c:384
SCIP_NODE * SCIPgetBestNode(SCIP *scip)
Definition: scip_tree.c:368
#define SCIP_Bool
Definition: def.h:93
int SCIPgetDepth(SCIP *scip)
Definition: scip_tree.c:670
type definitions for branch and bound tree
SCIP_NODE * SCIPgetFocusNode(SCIP *scip)
Definition: scip_tree.c:72
SCIP_NODE * SCIPgetPrioSibling(SCIP *scip)
Definition: scip_tree.c:304
SCIP_RETCODE SCIPprintNodeRootPath(SCIP *scip, SCIP_NODE *node, FILE *file)
Definition: scip_tree.c:529
int SCIPgetRepropdepth(SCIP *scip)
Definition: scip_tree.c:512
SCIP_NODE * SCIPgetPrioChild(SCIP *scip)
Definition: scip_tree.c:288
SCIP_NODE * SCIPgetBestChild(SCIP *scip)
Definition: scip_tree.c:320
SCIP_NODE * SCIPgetBestLeaf(SCIP *scip)
Definition: scip_tree.c:352
common defines and data types used in all packages of SCIP
void SCIPsetFocusnodeLP(SCIP *scip, SCIP_Bool solvelp)
Definition: scip_tree.c:625