Connect++ 0.6.1
A fast, readable connection prover for first-order logic.
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Public Member Functions | Private Member Functions | Private Attributes | Static Private Attributes | Friends | List of all members
StackProver Class Reference

Prover using a pair of stacks to conduct the proof search. More...

#include <StackProver.hpp>

Collaboration diagram for StackProver:
Collaboration graph
[legend]

Public Member Functions

 StackProver ()
 You only need a basic constructor.
 
 StackProver (const StackProver &)=delete
 Don't try to copy this.
 
 StackProver (const StackProver &&)=delete
 
StackProver & operator= (const StackProver &)=delete
 
StackProver & operator= (const StackProver &&)=delete
 
std::tuple< VariableIndex *, FunctionIndex *, PredicateIndex *, TermIndex * > get_indexes ()
 Straightforward get method.
 
string get_status () const
 Straightforward get method.
 
void set_timeout (chrono::steady_clock::time_point time)
 Set a timeout.
 
void set_problem_path (fs::path &p)
 Set the path for the problem being solved.
 
void set_num_preds (size_t)
 Set the number of predicates.
 
void read_from_tptp_file (const string &, bool &, size_t &)
 Obviously, reads a problem from a TPTP file.
 
void add_equality_axioms (Predicate *)
 After reading a problem in which = and/or != appears, add the axioms for equality.
 
void deterministic_reorder (uint32_t n)
 Deterministically reorder the matrix n times.
 
void random_reorder ()
 Randomly reorder the matrix.
 
void random_reorder_literals ()
 Randomly reorder the literals in each clause in the matrix.
 
void show_matrix ()
 Show a nicely formatted matrix.
 
Matrix & get_matrix ()
 Get a reference to the matrix.
 
bool problem_is_cnf_only () const
 Find out whether the problem is CNF only.
 
bool problem_has_true_conjecture () const
 Find out whether the problem's conjecture
is $true.
 
bool problem_has_false_conjecture () const
 Find out whether the problem's conjecture
is $false.
 
bool problem_has_missing_conjecture () const
 Find out whether the problem's conjecture
is missing, in the sense that it didn't appear in the input file.
 
bool problem_has_negated_conjecture_removed () const
 Find out whether the problem's
negated conjecture was simplified out.
 
bool problem_has_fof_axioms () const
 Find out from the parser whether the problem had axioms before simplification.
 
bool simplified_problem_has_fof_axioms () const
 Find out from the parser whether the problem had axioms after simplification.
 
string get_tptp_conversion_string () const
 
void show_tptp_proof ()
 Show a Prolog-formatted proof.
 
ProverOutcome prove ()
 Here is where the magic happens.
 
vector< pair< string, vector< size_t > > > get_internal_proof () const
 Get an internal representation of the proof stack.
 
void show_statistics () const
 Display counts of number of extensions tried and so on.
 
void show_full_statistics (size_t) const
 Display counts of number of extensions tried and so on, as well as numbers per second.
 
void show_matrix () const
 
void show_path () const
 
void show_stack ()
 
void show_right_stack ()
 
void show_term_index ()
 

Private Member Functions

ProverResult go ()
 This runs the proof search from a given Start Move.
 
void populate_stack_item ()
 Fill the vector of possible actions with everything available.
 
void extend_with_action ()
 Take a single inference (action) and update the stacks accordingly.
 
bool axiom ()
 Test to see if you're at an axiom.
 
void process_axiom_forward ()
 Start a right branch to continue from an axiom.
 
void backtrack_once ()
 Basic, single step backtrack on the stack.
 
void reduction_backtrack ()
 One of several different kinds of backtracking.
 
void lemmata_backtrack ()
 One of several different kinds of backtracking.
 
void left_extension_backtrack ()
 One of several different kinds of backtracking.
 
void right_extension_backtrack ()
 One of several different kinds of backtracking.
 
void set_up_start_clauses ()
 The start clauses to use depend on the settings, and the settings can change.
 
void reset_for_start ()
 Reset everything so that you can start from a specified start clause.
 

Private Attributes

size_t num_preds
 How many prdicates does the problem of interest have?
 
VariableIndex var_index
 This class needs one of each kind of index to keep track of Variables, Terms etc.
 
FunctionIndex fun_index
 This class needs one of each kind of index to keep track of Variables, Terms etc.
 
TermIndex term_index
 This class needs one of each kind of index to keep track of Variables, Terms etc.
 
PredicateIndex pred_index
 This class needs one of each kind of index to keep track of Variables, Terms etc.
 
SubstitutionStack sub_stack
 There is a separate stack to make application and removal of substitutions straightforward.
 
vector< StartClauseStatus > results
 This is populated by the StackProver::set_up_start_clauses method.
 
Matrix matrix
 A copy of the matrix you're working with.
 
ClauseCopyCache clause_cache
 Manages caching of copies of clauses from the matrix.
 
SimplePath path
 At any point in the search process this is a copy of the path for the current node in the proof being constructed.
 
Clause new_C
 At any point in the search process this is a copy of the clause for the current node in the proof being constructed.
 
Lemmata lemmata
 At any point in the search process this is a copy of the list of lemmas for the current node in the proof being constructed.
 
Unifier u
 We need a single Unifier to use throughout the process.
 
InferenceItem action
 Stores the next action from the current StackItem.
 
size_t si
 Index of the current StackItem.
 
uint32_t current_depth_limit
 Self-explanatary.
 
uint32_t current_depth
 Self-explanatary.
 
bool depth_limit_reached
 Self-explanatary.
 
string status
 Problem status, if found in input file.
 
string tptp_conversion_string
 TPTP-friendly description of the clause conversion.
 
Stack stack
 Main stack: this is constructed by the search process and, if completed, represents a proof.
 
Stack right_branch_stack
 We build the proof by trying the left branches of extensions first: this stack keeps track of the right branches that we need to come back to.
 
bool backtrack
 Are we moving up or down the stack?
 
ProofPrinter proof_printer
 You need one of these to print LaTeX output or any kind of proof certificate.
 
fs::path problem_path
 Path for the problem of interest.
 
Interval output_interval
 How often do you output updates about progress?
 
uint32_t proof_count
 If we're searching for multiple proofs, keep count
of which one this is.
 
bool use_timeout
 Are we using a timeout?
 
chrono::steady_clock::time_point end_time
 When do we stop because of a timeout?
 
verbose_print::VPrint show
 Set up printing according to verbosity.
 
bool cnf_only
 Keep track of whether there were any FOF formulas in the problem file.
 
bool conjecture_true
 Keep track of whether the parser found the conjecture to be true.
 
bool conjecture_false
 Keep track of whether the parser found the conjecture to be false.
 
bool conjecture_missing
 Keep track of whether the parser found a conjecture in the problem file.
 
bool negated_conjecture_removed
 Keep track of whether the parser simplified the conjecture away.
 
bool fof_has_axioms
 Keep track of whether the parser found that it's an FOF problem with axioms before simplification.
 
bool simplified_fof_has_axioms
 Keep track of whether the parser found that it's an FOF problem with axioms after simplification.
 

Static Private Attributes

static uint32_t reductions_tried = 0
 We'll be keeping some simple statistics about the search process.
 
static uint32_t extensions_tried = 0
 We'll be keeping some simple statistics about the search process.
 
static uint32_t lemmata_tried = 0
 We'll be keeping some simple statistics about the search process.
 
static uint32_t right_branches_started = 0
 We'll be keeping some simple statistics about the search process.
 

Friends

ostream & operator<< (ostream &out, const StackProver &p)
 

Detailed Description

Prover using a pair of stacks to conduct the proof search.

This version is a straightforward translation of the proof method to search for a tree with all its leaves being axioms. However, by not using recursion we retain the ability to fully control backtracking and therefore, amongst other things, find all possible proofs.

This is really the main class for Connect++, and everything else essentially exists to support it. There's a lot going on here so hang on to your hat!

This is also one of only a small number of places where you'll need to modify stuff to incorporate machine learning. The main advice is simple: take notice of the comments that point out where to do this, and be very careful to leave the general stack manipulation code alone unless you really know what you're doing, because that stuff is quite easy to break.

Definition at line 76 of file StackProver.hpp.

Constructor & Destructor Documentation

◆ StackProver()

StackProver::StackProver ( )

You only need a basic constructor.

Definition at line 33 of file StackProver.cpp.

34: num_preds(0)
35, var_index()
36, fun_index()
37, term_index()
38, pred_index()
39, sub_stack()
40, results()
41, matrix()
42, clause_cache()
43, path()
44, new_C()
45, lemmata()
46, u()
47, action(InferenceItemType::Start)
48, si(0)
49, current_depth_limit(0)
50, current_depth(1)
51, depth_limit_reached(false)
52, status()
53, tptp_conversion_string()
54, stack()
55, right_branch_stack()
56, backtrack(false)
57, proof_printer(&stack)
58, problem_path()
59, output_interval(params::output_frequency)
60, proof_count(0)
61, use_timeout(false)
62, end_time()
63, show(params::verbosity)
64, cnf_only(false)
65, conjecture_true(false)
66, conjecture_false(false)
67, conjecture_missing(false)
68, negated_conjecture_removed(false)
69, fof_has_axioms(false)
70, simplified_fof_has_axioms(false)
71{}
StackProver::depth_limit_reached
bool depth_limit_reached
Self-explanatary.
Definition StackProver.hpp:169
StackProver::status
string status
Problem status, if found in input file.
Definition StackProver.hpp:173
StackProver::results
vector< StartClauseStatus > results
This is populated by the StackProver::set_up_start_clauses method.
Definition StackProver.hpp:118
StackProver::negated_conjecture_removed
bool negated_conjecture_removed
Keep track of whether the parser simplified the conjecture away.
Definition StackProver.hpp:340
StackProver::stack
Stack stack
Main stack: this is constructed by the search process and, if completed, represents a proof.
Definition StackProver.hpp:182
StackProver::clause_cache
ClauseCopyCache clause_cache
Manages caching of copies of clauses from the matrix.
Definition StackProver.hpp:127
StackProver::current_depth_limit
uint32_t current_depth_limit
Self-explanatary.
Definition StackProver.hpp:161
StackProver::action
InferenceItem action
Stores the next action from the current StackItem.
Definition StackProver.hpp:153
StackProver::num_preds
size_t num_preds
How many prdicates does the problem of interest have?
Definition StackProver.hpp:82
StackProver::fof_has_axioms
bool fof_has_axioms
Keep track of whether the parser found that it's an FOF problem with axioms before simplification.
Definition StackProver.hpp:345
StackProver::matrix
Matrix matrix
A copy of the matrix you're working with.
Definition StackProver.hpp:122
StackProver::pred_index
PredicateIndex pred_index
This class needs one of each kind of index to keep track of Variables, Terms etc.
Definition StackProver.hpp:102
StackProver::proof_printer
ProofPrinter proof_printer
You need one of these to print LaTeX output or any kind of proof certificate.
Definition StackProver.hpp:197
StackProver::cnf_only
bool cnf_only
Keep track of whether there were any FOF formulas in the problem file.
Definition StackProver.hpp:324
StackProver::path
SimplePath path
At any point in the search process this is a copy of the path for the current node in the proof being...
Definition StackProver.hpp:133
StackProver::fun_index
FunctionIndex fun_index
This class needs one of each kind of index to keep track of Variables, Terms etc.
Definition StackProver.hpp:92
StackProver::lemmata
Lemmata lemmata
At any point in the search process this is a copy of the list of lemmas for the current node in the p...
Definition StackProver.hpp:145
StackProver::current_depth
uint32_t current_depth
Self-explanatary.
Definition StackProver.hpp:165
StackProver::tptp_conversion_string
string tptp_conversion_string
TPTP-friendly description of the clause conversion.
Definition StackProver.hpp:177
StackProver::simplified_fof_has_axioms
bool simplified_fof_has_axioms
Keep track of whether the parser found that it's an FOF problem with axioms after simplification.
Definition StackProver.hpp:350
StackProver::conjecture_missing
bool conjecture_missing
Keep track of whether the parser found a conjecture in the problem file.
Definition StackProver.hpp:336
StackProver::term_index
TermIndex term_index
This class needs one of each kind of index to keep track of Variables, Terms etc.
Definition StackProver.hpp:97
StackProver::proof_count
uint32_t proof_count
If we're searching for multiple proofs, keep count of which one this is.
Definition StackProver.hpp:233
StackProver::conjecture_false
bool conjecture_false
Keep track of whether the parser found the conjecture to be false.
Definition StackProver.hpp:332
StackProver::var_index
VariableIndex var_index
This class needs one of each kind of index to keep track of Variables, Terms etc.
Definition StackProver.hpp:87
StackProver::si
size_t si
Index of the current StackItem.
Definition StackProver.hpp:157
StackProver::conjecture_true
bool conjecture_true
Keep track of whether the parser found the conjecture to be true.
Definition StackProver.hpp:328
StackProver::backtrack
bool backtrack
Are we moving up or down the stack?
Definition StackProver.hpp:192
StackProver::end_time
chrono::steady_clock::time_point end_time
When do we stop because of a timeout?
Definition StackProver.hpp:241
StackProver::new_C
Clause new_C
At any point in the search process this is a copy of the clause for the current node in the proof bei...
Definition StackProver.hpp:139
StackProver::problem_path
fs::path problem_path
Path for the problem of interest.
Definition StackProver.hpp:201
StackProver::use_timeout
bool use_timeout
Are we using a timeout?
Definition StackProver.hpp:237
StackProver::right_branch_stack
Stack right_branch_stack
We build the proof by trying the left branches of extensions first: this stack keeps track of the rig...
Definition StackProver.hpp:188
StackProver::sub_stack
SubstitutionStack sub_stack
There is a separate stack to make application and removal of substitutions straightforward.
Definition StackProver.hpp:107
StackProver::show
verbose_print::VPrint show
Set up printing according to verbosity.
Definition StackProver.hpp:245
StackProver::u
Unifier u
We need a single Unifier to use throughout the process.
Definition StackProver.hpp:149
StackProver::output_interval
Interval output_interval
How often do you output updates about progress?
Definition StackProver.hpp:205

Member Function Documentation

◆ add_equality_axioms()

void StackProver::add_equality_axioms ( Predicate * equals_predicate)

After reading a problem in which = and/or != appears, add the axioms for equality.

Parameters
equals_predicatePointer to a Predicate representing equals. This will have been obtained as an output from parsing the input file.

Definition at line 128 of file StackProver.cpp.

128 {
129 /*
130 * Equality axioms as described in Handbook of Automated
131 * Reasoning, Volume 1, page 615.
132 */
133 Arity max_fun_arity = fun_index.find_maximum_arity();
134 Arity max_pred_arity = pred_index.find_maximum_arity();
135 /*
136 * You need at least three variables to describe these, and
137 * twice as many as the arity of the biggest predicate or
138 * function.
139 */
140 uint32_t max_arity = max_fun_arity;
141 if (max_pred_arity > max_arity)
142 max_arity = max_pred_arity;
143 if (max_arity < 3)
144 max_arity = 3;
145 vector<Term*> xs;
146 vector<Term*> ys;
147 string xvar("__eqx_");
148 string yvar("__eqy_");
149 for (size_t i = 0; i < max_arity; i++) {
150 Variable* xvarp = var_index.add_named_var(xvar + std::to_string(i));
151 Variable* yvarp = var_index.add_named_var(yvar + std::to_string(i));
152 xs.push_back(term_index.add_variable_term(xvarp));
153 ys.push_back(term_index.add_variable_term(yvarp));
154 }
155 /*
156 * How you construct these depends on which representation you're using.
157 * It's easy enough to show that the difference is only a case
158 * of swapping negations. See for example "Equality Preprocessing in
159 * Connection Calculi", Oliver and Otten.
160 */
161 bool pol = !params::positive_representation;
162 uint32_t n_added = 0;
163 /*
164 * Axiom for reflexivity.
165 */
166 vector<Term*> ref;
167 ref.push_back(xs[0]);
168 ref.push_back(xs[0]);
169 Literal reflexive(equals_predicate, ref, 2, pol);
170 Clause ref_c;
171 ref_c.add_lit(reflexive);
172 matrix.add_clause(ref_c, "equality");
173 n_added++;
174 /*
175 * Axiom for symmetry.
176 */
177 vector<Term*> xy;
178 xy.push_back(xs[0]);
179 xy.push_back(xs[1]);
180 vector<Term*> yx;
181 yx.push_back(xs[1]);
182 yx.push_back(xs[0]);
183 Literal sym1(equals_predicate, xy, 2, !pol);
184 Literal sym2(equals_predicate, yx, 2, pol);
185 Clause sym_c;
186 sym_c.add_lit(sym1);
187 sym_c.add_lit(sym2);
188 matrix.add_clause(sym_c, "equality");
189 n_added++;
190 /*
191 * Axiom for transitivity.
192 */
193 vector<Term*> yz;
194 yz.push_back(xs[1]);
195 yz.push_back(xs[2]);
196 vector<Term*> xz;
197 xz.push_back(xs[0]);
198 xz.push_back(xs[2]);
199 Literal tr1(equals_predicate, xy, 2, !pol);
200 Literal tr2(equals_predicate, yz, 2, !pol);
201 Literal tr3(equals_predicate, xz, 2, pol);
202 Clause tr_c;
203 tr_c.add_lit(tr1);
204 tr_c.add_lit(tr2);
205 tr_c.add_lit(tr3);
206 matrix.add_clause(tr_c, "equality");
207 n_added++;
208 /*
209 * Function substitution.
210 */
211 for (size_t j = 0; j < fun_index.get_size(); j++) {
212 Function* p = fun_index[j];
213 Arity ar = p->get_arity();
214 if (ar > 0) {
215 Clause c;
216 vector<Term*> x1xn;
217 vector<Term*> y1yn;
218 for (size_t i = 0; i < ar; i++) {
219 x1xn.push_back(xs[i]);
220 y1yn.push_back(ys[i]);
221 vector<Term*> xiyi;
222 xiyi.push_back(xs[i]);
223 xiyi.push_back(ys[i]);
224 Literal eq_lit(equals_predicate, xiyi, 2, !pol);
225 c.add_lit(eq_lit);
226 }
227 vector<Term*> t;
228 t.push_back(term_index.add_function_term(p, x1xn));
229 t.push_back(term_index.add_function_term(p, y1yn));
230 Literal f_lit(equals_predicate, t, 2, pol);
231 c.add_lit(f_lit);
232 matrix.add_clause(c, "equality");
233 n_added++;
234 }
235 }
236 /*
237 * Predicate substitution.
238 */
239 for (size_t j = 0; j < pred_index.get_num_preds(); j++) {
240 Predicate* p = pred_index[j];
241 Arity ar = p->get_arity();
242 if (ar > 0 && p != equals_predicate) {
243 Clause c;
244 vector<Term*> x1xn;
245 vector<Term*> y1yn;
246 for (size_t i = 0; i < ar; i++) {
247 x1xn.push_back(xs[i]);
248 y1yn.push_back(ys[i]);
249 vector<Term*> xiyi;
250 xiyi.push_back(xs[i]);
251 xiyi.push_back(ys[i]);
252 Literal eq_lit(equals_predicate, xiyi, 2, !pol);
253 c.add_lit(eq_lit);
254 }
255 Literal p_lit1(p, x1xn, ar, !pol);
256 Literal p_lit2(p, y1yn, ar, pol);
257 c.add_lit(p_lit1);
258 c.add_lit(p_lit2);
259 matrix.add_clause(c, "equality");
260 n_added++;
261 }
262 }
263 /*
264 * Distinct objects
265 */
266 Arity min_arity = fun_index.find_minimum_arity();
267 if (!params::no_distinct_objects && min_arity == 0) {
268 vector<Term*> all_distinct_constants;
269 vector<Term*> empty_args;
270 for (size_t i = 0; i < fun_index.get_size(); i++) {
271 Function* p = fun_index[i];
272 Arity ar = p->get_arity();
273 // Remember, you don't want to do this for Skolem constants.
274 string name = p->get_name();
275 string prefix = name.string::substr(0,params::unique_skolem_prefix.length());
276 bool is_skolem = (params::unique_skolem_prefix.string::compare(0, string::npos, prefix) == 0) &&
277 (params::unique_skolem_prefix.length() < name.length());
278 bool is_quoted = (name[0] == '\"' && name[name.size() - 1] == '\"');
279 if (ar == 0 &&
280 !is_skolem &&
281 (params::all_distinct_objects || is_quoted)) {
282 Term* t = term_index.add_function_term(p, empty_args);
283 all_distinct_constants.push_back(t);
284 }
285 }
286 size_t s = all_distinct_constants.size();
287 if (s > 1) {
288 for (size_t i = s - 1; i > 0; i--) {
289 for (size_t j = 0; j < i; j++) {
290 Clause c;
291 vector<Term*> args;
292 args.push_back(all_distinct_constants[i]);
293 args.push_back(all_distinct_constants[j]);
294 Literal eq_lit(equals_predicate, args, 2, !pol);
295 c.add_lit(eq_lit);
296 matrix.add_clause(c, "distinct_objects");
297 n_added++;
298 }
299 }
300 }
301 }
302 matrix.set_num_equals(n_added);
303}
Clause
Representation of clauses.
Definition Clause.hpp:52
Clause::add_lit
void add_lit(const Literal &)
Add a literal, making sure you don't duplicate.
Definition Clause.cpp:96
Function
Basic representation of functions.
Definition Function.hpp:54
Function::get_arity
Arity get_arity() const
Most basic access function.
Definition Function.hpp:88
Function::get_name
string get_name() const
Most basic access function.
Definition Function.hpp:84
FunctionIndex::find_minimum_arity
Arity find_minimum_arity() const
Find the smallest arity appearing for any Function in the index.
Definition FunctionIndex.cpp:81
FunctionIndex::get_size
size_t get_size() const
Self-explanatory.
Definition FunctionIndex.hpp:96
FunctionIndex::find_maximum_arity
Arity find_maximum_arity() const
Find the largest arity appearing for any Function in the index.
Definition FunctionIndex.cpp:71
Literal
Basic representation of literals, bundling together (pointers to) a Predicate, a collection of argume...
Definition Literal.hpp:50
Matrix::add_clause
void add_clause(Clause &, string="")
Add a Clause to the Matrix and update the index accordingly.
Definition Matrix.cpp:97
Matrix::set_num_equals
void set_num_equals(uint32_t n)
Straightforward set method.
Definition Matrix.hpp:297
Predicate
Basic representation of predicates: here just names, ids and arities.
Definition Predicate.hpp:51
Predicate::get_arity
Arity get_arity() const
Basic get method.
Definition Predicate.hpp:90
PredicateIndex::get_num_preds
size_t get_num_preds() const
Basic get method.
Definition PredicateIndex.hpp:92
PredicateIndex::find_maximum_arity
Arity find_maximum_arity() const
Find the largest arity appearing in the index.
Definition PredicateIndex.cpp:66
Term
General representation of terms.
Definition Term.hpp:62
TermIndex::add_function_term
Term * add_function_term(Function *, const vector< Term * > &)
Self-explanatory: add a Term containing a function to the index.
Definition TermIndex.cpp:56
TermIndex::add_variable_term
Term * add_variable_term(Variable *)
Self-explanatory: add a Term containing a variable to the index.
Definition TermIndex.cpp:41
Variable
Basic representation of variables.
Definition Variable.hpp:58
VariableIndex::add_named_var
Variable * add_named_var(const string &)
Add a variable with the specified name to the index.
Definition VariableIndex.cpp:47

◆ axiom()

bool StackProver::axiom ( )
private

Test to see if you're at an axiom.

Definition at line 323 of file StackProver.cpp.

323 {
324 return stack[si].c.empty();
325}
Stack::empty
bool empty() const
Exact analogue of the same function for vector<>.
Definition Stack.hpp:88

◆ backtrack_once()

void StackProver::backtrack_once ( )
private

Basic, single step backtrack on the stack.

Careful though: you need to treat the depth of the tree correctly if you want to keep track of it.

Definition at line 533 of file StackProver.cpp.

533 {
534 backtrack = true;
535 stack.pop_back();
536 si--;
537 current_depth = stack[si].depth;
538}
Stack::pop_back
void pop_back()
Exact analogue of the same function for vector<>. BUT - importantly - avoid calling the StackItem des...
Definition Stack.hpp:116

◆ deterministic_reorder()

void StackProver::deterministic_reorder ( uint32_t n)
inline

Deterministically reorder the matrix n times.

Parameters
nNumber of times to reorder.

Definition at line 427 of file StackProver.hpp.

427 {
428 matrix.deterministic_reorder(n);
429 }
Matrix::deterministic_reorder
void deterministic_reorder(size_t)
Deterministic reorder of the clauses.
Definition Matrix.cpp:133

◆ extend_with_action()

void StackProver::extend_with_action ( )
private

Take a single inference (action) and update the stacks accordingly.

Definition at line 327 of file StackProver.cpp.

327 {
328 /*
329 * Add a new StackItem using the next action from the list stored
330 * in the StackItem currently in play. If necessary, also
331 * add something to right_branch_stack. Populate the new list of
332 * actions and update si.
333 */
334 current_depth++;
335 /*
336 * Why are the scope rules for switch so odd???
337 */
338 Clause old_C;
339 Lemmata old_Lem;
340 Literal neg_lit;
341 UnificationOutcome outcome;
342 Substitution sig;
343 Literal ext_L;
344 switch (action.T) {
345 //----------------------------------------------------------------------
346 //----------------------------------------------------------------------
347 //----------------------------------------------------------------------
348 // Lemmas.
349 //----------------------------------------------------------------------
350 //----------------------------------------------------------------------
351 //----------------------------------------------------------------------
352 case InferenceItemType::Lemma:
353 lemmata_tried++;
354 /*
355 * If you are restricting backtracking for lemmas then
356 * at this point you can remove all alternatives.
357 */
358 if (params::limit_bt_lemmas)
359 stack[si].restrict_backtrack();
360 /*
361 * Work out the new state.
362 */
363 new_C = stack[si].c;
364 new_C.drop_literal(action.Lindex);
365 path = stack[si].p;
366 lemmata = stack[si].l;
367 /*
368 * Extend the stack.
369 */
370 stack.emplace_back(StackItemType::Lemmata, new_C, path,
371 lemmata, current_depth);
372 stack.back().set_this_action(action);
373 break;
374 //----------------------------------------------------------------------
375 //----------------------------------------------------------------------
376 //----------------------------------------------------------------------
377 // Reduction.
378 //----------------------------------------------------------------------
379 //----------------------------------------------------------------------
380 //----------------------------------------------------------------------
381 case InferenceItemType::Reduction:
382 reductions_tried++;
383 /*
384 * If you are restricting backtracking for reductions then
385 * at this point you can remove all alternatives.
386 */
387 if (params::limit_bt_reductions)
388 stack[si].restrict_backtrack();
389 /*
390 * Reductions have a substitution, so apply it and remember
391 * in case you need to undo it later.
392 */
393 action.sigma.apply();
394 sub_stack.push_all(action.sigma);
395 /*
396 * Work out the new state.
397 */
398 new_C = stack[si].c;
399 new_C.drop_literal(action.Lindex);
400 path = stack[si].p;
401 lemmata = stack[si].l;
402 lemmata.push_back(action.L);
403 /*
404 * Extend the stack.
405 */
406 stack.emplace_back(StackItemType::Reduction, new_C, path,
407 lemmata, action.sigma, current_depth);
408 stack.back().set_this_action(action);
409 break;
410 //----------------------------------------------------------------------
411 //----------------------------------------------------------------------
412 //----------------------------------------------------------------------
413 // Extension.
414 //----------------------------------------------------------------------
415 //----------------------------------------------------------------------
416 //----------------------------------------------------------------------
417 case InferenceItemType::Extension:
418 extensions_tried++;
419 /*
420 * You're going to generate new variables, so remember where to
421 * backtrack to.
422 */
423 //var_index.add_backtrack_point();
424 /*
425 * This is an Extension, so you're going to add something to
426 * right_branch_stack.
427 */
428 path = stack[si].p;
429 old_C = stack[si].c;
430 old_C.drop_literal(action.Lindex);
431 old_Lem = stack[si].l;
432 old_Lem.push_back(action.L);
433 /*
434 * DON'T do populate_stack_item here! That can wait until you actually
435 * use the right branch. In fact it *has* to wait because we might
436 * apply substitutions that affect it.
437 */
438 right_branch_stack.emplace_back(StackItemType::RightBranch, old_C,
439 path, old_Lem, current_depth);
440 /*
441 * The right branch needs to know where to restrict backtracking.
442 */
443 right_branch_stack.back().set_bt_restriction_index(stack.size() - 1);
444 /*
445 * Now you can deal with the left branch.
446 */
447
448 //matrix.get_literal_clause_pair(action.index_in_LC_index, action.index_to_LC, ext_L, new_C);
449 //new_C.make_copy_with_new_vars(ext_L, new_C, var_index, term_index);
450
451 clause_cache.make_copy_with_new_variables(action.C_2, new_C, matrix, var_index, term_index);
452 ext_L = new_C[action.Lprime];
453 new_C.drop_literal(action.Lprime);
454 /*
455 * Extensions have a substitution, so apply it and remember
456 * in case you need to undo it later.
457 */
458 neg_lit = action.L;
459 neg_lit.invert();
460 outcome = u(neg_lit, ext_L);
461 sig = u.get_substitution();
462 u.backtrack();
463 sig.apply();
464 sub_stack.push_all(sig);
465 /*
466 * Work out the new state.
467 */
468 path.push(action.L);
469 lemmata = stack[si].l;
470 /*
471 * Extend the stack.
472 */
473 stack.emplace_back(StackItemType::LeftBranch, new_C, path,
474 lemmata, sig, current_depth);
475 stack.back().set_this_action(action);
476 break;
477 default:
478 cerr << "PANIC!!! You should only have a lemmata, reduction or an extension here!"
479 << endl;
480 break;
481 }
482 /*
483 * Finally, move si on and work out the next bunch of possible actions.
484 */
485 si++;
486 populate_stack_item();
487}
ClauseCopyCache::make_copy_with_new_variables
void make_copy_with_new_variables(size_t, Clause &, const Matrix &, VariableIndex &, TermIndex &)
If there is a copy cached, replace the parameter with it. Otherwise, use the parameter to actually ma...
Definition ClauseCopyCache.cpp:46
Clause::drop_literal
void drop_literal(LitNum)
Get rid of the specified Literal.
Definition Clause.cpp:168
Lemmata
Representation of the lemma list.
Definition Lemmata.hpp:49
Lemmata::push_back
void push_back(const Literal &)
Self-explanatory.
Definition Lemmata.cpp:28
Stack::emplace_back
void emplace_back(StackItemType sit, const Clause &_c, const SimplePath &_p, const Lemmata &_l, uint32_t _d)
(Almost!) exact analogue of the same function for vector<>.
Definition Stack.hpp:132
Stack::size
size_t size() const
Exact analogue of the same function for vector<>.
Definition Stack.hpp:94
Stack::back
StackItem & back()
Exact analogue of the same function for vector<>.
Definition Stack.hpp:109
StackProver::lemmata_tried
static uint32_t lemmata_tried
We'll be keeping some simple statistics about the search process.
Definition StackProver.hpp:223
StackProver::populate_stack_item
void populate_stack_item()
Fill the vector of possible actions with everything available.
Definition StackProver.cpp:305
StackProver::extensions_tried
static uint32_t extensions_tried
We'll be keeping some simple statistics about the search process.
Definition StackProver.hpp:218
StackProver::reductions_tried
static uint32_t reductions_tried
We'll be keeping some simple statistics about the search process.
Definition StackProver.hpp:213
Substitution
General representation of a substitution.
Definition Substitution.hpp:57
Substitution::apply
void apply() const
Apply a substitution everywhere.
Definition Substitution.cpp:56
SubstitutionStack::push_all
void push_all(Substitution &)
Take all the substitutions provided and add the corresponding variables to the stack.
Definition SubstitutionStack.cpp:28
Unifier::backtrack
void backtrack()
Apply the backtracking process to the substitution that has been constructed.
Definition Unifier.cpp:195
Unifier::get_substitution
Substitution get_substitution() const
Trivial get methods for the result.
Definition Unifier.hpp:122
InferenceItem::Lindex
LitNum Lindex
The index of the literal within the clause being used.
Definition InferenceItem.hpp:73
InferenceItem::Lprime
LitNum Lprime
The index of the literal in C_2 being used.
Definition InferenceItem.hpp:82
InferenceItem::sigma
Substitution sigma
A copy of the substitution that makes the rule applicable. This may or may not be reusable,...
Definition InferenceItem.hpp:89
InferenceItem::L
Literal L
The Literal that is used to make the inference.
Definition InferenceItem.hpp:69
InferenceItem::C_2
ClauseNum C_2
For extensions, the number of the clause for which a fresh copy is being made.
Definition InferenceItem.hpp:78
InferenceItem::T
InferenceItemType T
What kind of inference is this?
Definition InferenceItem.hpp:65
StackItem::set_bt_restriction_index
void set_bt_restriction_index(size_t i)
Basic set method.
Definition StackItem.hpp:195
StackItem::set_this_action
void set_this_action(const InferenceItem &inf_i)
Basic set method.
Definition StackItem.hpp:189

◆ get_indexes()

std::tuple< VariableIndex *, FunctionIndex *, PredicateIndex *, TermIndex * > StackProver::get_indexes ( )
inline

Straightforward get method.

Definition at line 366 of file StackProver.hpp.

366 {
367 auto result = std::make_tuple(&var_index, &fun_index, &pred_index, &term_index);
368 return result;
369 }

◆ get_internal_proof()

vector< pair< string, vector< size_t > > > StackProver::get_internal_proof ( ) const

Get an internal representation of the proof stack.

Definition at line 1237 of file StackProver.cpp.

1237 {
1238 return proof_printer.make_internal();
1239}
ProofPrinter::make_internal
vector< pair< string, vector< size_t > > > make_internal() const
Make a simple data structure representing the proof stack.
Definition ProofPrinter.cpp:402

◆ get_matrix()

Matrix & StackProver::get_matrix ( )
inline

Get a reference to the matrix.

Definition at line 453 of file StackProver.hpp.

453 {
454 return matrix;
455 };

◆ get_status()

string StackProver::get_status ( ) const
inline

Straightforward get method.

Definition at line 373 of file StackProver.hpp.

373{ return status; }

◆ get_tptp_conversion_string()

string StackProver::get_tptp_conversion_string ( ) const
inline

Definition at line 506 of file StackProver.hpp.

506 {
507 return tptp_conversion_string;
508 }

◆ go()

ProverResult StackProver::go ( )
private

This runs the proof search from a given Start Move.

Definition at line 640 of file StackProver.cpp.

640 {
641 /*
642 * Having set up a single entry on the stack, containing a start
643 * state, search for a proof.
644 *
645 * Either you return by ending at the start state with nothing left
646 * to try, by finding a proof, by depth limiting or by timing out.
647 *
648 * The backtrack variable is important here - when true you are
649 * (surprise surprise) backtracking. So mostly each case in the
650 * following switch is divided according to whether you're going
651 * forward or backtracking.
652 */
653 while(true) {
654 /*
655 * Test for and deal with a timeout.
656 */
657 if (use_timeout && chrono::steady_clock::now() > end_time)
658 return ProverResult::TimeOut;
659 /*
660 * Say what's going on.
661 */
662 if (output_interval.tick() && params::verbosity >= 2) {
663 cout << cursor_symbols::Cursor::to_column(1);
664 cout << cursor_symbols::Cursor::erase_line(2);
665 cout << "Reductions: " << reductions_tried << " Extensions: " << extensions_tried;
666 cout << " Lemmata: " << lemmata_tried << " Right branches: " << right_branches_started;
667 cout << " Stack size: " << stack.size();
668 cout.flush();
669 }
670 /*
671 * si must point to the back of the stack at this point.
672 *
673 * Remember that extend_with_action will deal with this for you.
674 */
675 switch (stack[si].item_type) {
676 //----------------------------------------------------------------
677 //----------------------------------------------------------------
678 //----------------------------------------------------------------
679 // Deal with the start state. Essentially straightforward. Just
680 // deal with a completed search, otherwise work out the
681 // possibly actions and get on with it.
682 //----------------------------------------------------------------
683 //----------------------------------------------------------------
684 //----------------------------------------------------------------
685 case StackItemType::Start:
686 backtrack = false;
687 action = stack[si].get_next_inference(matrix, u);
688 if (action.T == InferenceItemType::None)
689 return ProverResult::OptionsExhausted;
690 else
691 extend_with_action();
692 break;
693 //----------------------------------------------------------------
694 //----------------------------------------------------------------
695 //----------------------------------------------------------------
696 // Lemmas. Again, mostly straightforward.
697 //----------------------------------------------------------------
698 //----------------------------------------------------------------
699 //----------------------------------------------------------------
700 case StackItemType::Lemmata:
701 /*
702 * Operation is essentially similar to the reduction case.
703 *
704 * First deal with moving forward.
705 */
706 if (!backtrack) {
707 if (axiom()) {
708 /*
709 * Either you've found a proof or you try a right branch.
710 */
711 if (right_branch_stack.empty())
712 return ProverResult::Valid;
713 else
714 process_axiom_forward();
715 }
716 /*
717 * Backtrack because there's nothing left to try.
718 */
719 else {
720 action = stack[si].get_next_inference(matrix, u);
721 if (action.T == InferenceItemType::None)
722 lemmata_backtrack();
723 /*
724 * There must be something left to try, so try it.
725 */
726 else
727 extend_with_action();
728 }
729 }
730 /*
731 * We are moving down the stack.
732 */
733 else {
734 /*
735 * If you're backtracking then you need to jump over axioms.
736 */
737 if (axiom())
738 lemmata_backtrack();
739 /*
740 * If you're not at an axiom then you can start going forward
741 * again.
742 */
743 else
744 backtrack = false;
745 }
746 break;
747 //----------------------------------------------------------------
748 //----------------------------------------------------------------
749 //----------------------------------------------------------------
750 // Reduction. Almost identical to Lemmas, but note the
751 // slightly different backtracking requirement to take account
752 // of undoing the substitution.
753 //----------------------------------------------------------------
754 //----------------------------------------------------------------
755 //----------------------------------------------------------------
756 case StackItemType::Reduction:
757 /*
758 * We are moving up the stack.
759 */
760 if (!backtrack) {
761 if (axiom()) {
762 /*
763 * Either you've found a proof or you try a right branch.
764 */
765 if (right_branch_stack.empty())
766 return ProverResult::Valid;
767 else
768 process_axiom_forward();
769 }
770 /*
771 * Backtrack because there's nothing left to try.
772 */
773 else {
774 action = stack[si].get_next_inference(matrix, u);
775 if (action.T == InferenceItemType::None)
776 reduction_backtrack();
777 /*
778 * There must be something left to try, so try it.
779 */
780 else
781 extend_with_action();
782 }
783 }
784 /*
785 * We are moving down the stack.
786 */
787 else {
788 /*
789 * If you're backtracking then you need to jump over axioms.
790 */
791 if (axiom())
792 reduction_backtrack();
793 /*
794 * If you're not at an axiom then you can start going forward
795 * again.
796 */
797 else
798 backtrack = false;
799 }
800 break;
801 //----------------------------------------------------------------
802 //----------------------------------------------------------------
803 //----------------------------------------------------------------
804 // Left branch of Extension. Mostly similar to the Reduction
805 // and Lemma cases, but the backtrack is again different to
806 // take care of the new variables, the substitution, and the
807 // right_branch_stack.
808 //----------------------------------------------------------------
809 //----------------------------------------------------------------
810 //----------------------------------------------------------------
811 case StackItemType::LeftBranch:
812 /*
813 * Operation is essentially similar to the Reduction and
814 * Lemma cases. See those for corresponding comments.
815 */
816 if (!backtrack) {
817 if (axiom())
818 process_axiom_forward();
819 /*
820 * A little more involved here as it's where we deal with depth
821 * limiting.
822 */
823 else if ((stack[si].p.length() >= current_depth_limit)
824 && !matrix.is_ground(stack[si].this_action.C_2)) {
825 depth_limit_reached = true;
826 left_extension_backtrack();
827 }
828 else {
829 action = stack[si].get_next_inference(matrix, u);
830 if (action.T == InferenceItemType::None)
831 left_extension_backtrack();
832 else
833 extend_with_action();
834 }
835 }
836 /*
837 * We are moving down the stack.
838 */
839 else {
840 if (axiom())
841 left_extension_backtrack();
842 else
843 backtrack = false;
844 }
845 break;
846 //----------------------------------------------------------------
847 //----------------------------------------------------------------
848 //----------------------------------------------------------------
849 // Right branch of Extension. Mostly similar to the Reduction
850 // and Lemmata cases, but the backtrack is now much more
851 // delicate. See the documentation for right_extension_backtrack.
852 //----------------------------------------------------------------
853 //----------------------------------------------------------------
854 //----------------------------------------------------------------
855 case StackItemType::RightBranch:
856 /*
857 * Operation is essentially similar to the reduction case.
858 */
859 if (!backtrack) {
860 if (axiom()) {
861 if (right_branch_stack.empty())
862 return ProverResult::Valid;
863 else
864 process_axiom_forward();
865 }
866 else {
867 action = stack[si].get_next_inference(matrix, u);
868 if (action.T == InferenceItemType::None)
869 right_extension_backtrack();
870 else
871 extend_with_action();
872 }
873 }
874 /*
875 * We are moving down the stack.
876 */
877 else {
878 if (axiom())
879 right_extension_backtrack();
880 else
881 backtrack = false;
882 }
883 break;
884 //----------------------------------------------------------------
885 default:
886 cerr << "Something is VERY WRONG!" << endl;
887 break;
888 }
889 }
890 return ProverResult::Error;
891}
Interval::tick
bool tick()
Definition Interval.hpp:52
Matrix::is_ground
bool is_ground(size_t i) const
Is a particular Clause ground?
Definition Matrix.hpp:285
StackProver::process_axiom_forward
void process_axiom_forward()
Start a right branch to continue from an axiom.
Definition StackProver.cpp:489
StackProver::lemmata_backtrack
void lemmata_backtrack()
One of several different kinds of backtracking.
Definition StackProver.cpp:545
StackProver::axiom
bool axiom()
Test to see if you're at an axiom.
Definition StackProver.cpp:323
StackProver::extend_with_action
void extend_with_action()
Take a single inference (action) and update the stacks accordingly.
Definition StackProver.cpp:327
StackProver::left_extension_backtrack
void left_extension_backtrack()
One of several different kinds of backtracking.
Definition StackProver.cpp:549
StackProver::right_branches_started
static uint32_t right_branches_started
We'll be keeping some simple statistics about the search process.
Definition StackProver.hpp:228
StackProver::right_extension_backtrack
void right_extension_backtrack()
One of several different kinds of backtracking.
Definition StackProver.cpp:578
StackProver::reduction_backtrack
void reduction_backtrack()
One of several different kinds of backtracking.
Definition StackProver.cpp:540
cursor_symbols::Cursor::erase_line
static string erase_line(uint8_t n)
Definition cursor.hpp:158

◆ left_extension_backtrack()

void StackProver::left_extension_backtrack ( )
private

One of several different kinds of backtracking.

Definition at line 549 of file StackProver.cpp.

549 {
550 /*
551 * You're backtracking through a left branch, so you
552 * need to remember to get rid of the corresponding
553 * right branch as well.
554 */
555 right_branch_stack.pop_back();
556 //var_index.backtrack();
557 clause_cache.backtrack();
558 sub_stack.backtrack();
559 backtrack_once();
560}
ClauseCopyCache::backtrack
void backtrack()
Backtracking is just looking at the last copy supplied and undoing that action.
Definition ClauseCopyCache.cpp:61
StackProver::backtrack_once
void backtrack_once()
Basic, single step backtrack on the stack.
Definition StackProver.cpp:533
SubstitutionStack::backtrack
void backtrack()
Remove variables from the stack, and remove substitutions as you go, as far back as the most recent b...
Definition SubstitutionStack.cpp:36

◆ lemmata_backtrack()

void StackProver::lemmata_backtrack ( )
private

One of several different kinds of backtracking.

Definition at line 545 of file StackProver.cpp.

545 {
546 backtrack_once();
547}

◆ populate_stack_item()

void StackProver::populate_stack_item ( )
private

Fill the vector of possible actions with everything available.

Definition at line 305 of file StackProver.cpp.

305 {
306 /*
307 * Don't waste your time if the regularity test applies.
308 */
309 if (params::use_regularity_test && !path.test_for_regularity(new_C))
310 return;
311 /*
312 * Don't try to populate axioms.
313 */
314 if (new_C.size() == 0) {
315 return;
316 }
317 /*
318 * Extensions, reductions and lemmas.
319 */
320 stack[si].initialize(matrix);
321}
Clause::size
size_t size() const
Straightforward get method.
Definition Clause.hpp:78

◆ problem_has_false_conjecture()

bool StackProver::problem_has_false_conjecture ( ) const
inline

Find out whether the problem's conjecture
is $false.

Definition at line 474 of file StackProver.hpp.

474 {
475 return conjecture_false;
476 }

◆ problem_has_fof_axioms()

bool StackProver::problem_has_fof_axioms ( ) const
inline

Find out from the parser whether the problem had axioms before simplification.

Definition at line 496 of file StackProver.hpp.

496 {
497 return fof_has_axioms;
498 }

◆ problem_has_missing_conjecture()

bool StackProver::problem_has_missing_conjecture ( ) const
inline

Find out whether the problem's conjecture
is missing, in the sense that it didn't appear in the input file.

Definition at line 482 of file StackProver.hpp.

482 {
483 return conjecture_missing;
484 }

◆ problem_has_negated_conjecture_removed()

bool StackProver::problem_has_negated_conjecture_removed ( ) const
inline

Find out whether the problem's
negated conjecture was simplified out.

Definition at line 489 of file StackProver.hpp.

489 {
490 return negated_conjecture_removed;
491 }

◆ problem_has_true_conjecture()

bool StackProver::problem_has_true_conjecture ( ) const
inline

Find out whether the problem's conjecture
is $true.

Definition at line 467 of file StackProver.hpp.

467 {
468 return conjecture_true;
469 }

◆ problem_is_cnf_only()

bool StackProver::problem_is_cnf_only ( ) const
inline

Find out whether the problem is CNF only.

Definition at line 460 of file StackProver.hpp.

460 {
461 return cnf_only;
462 }

◆ process_axiom_forward()

void StackProver::process_axiom_forward ( )
private

Start a right branch to continue from an axiom.

You do this by taking the next available thing from the stack of right branches.

Definition at line 489 of file StackProver.cpp.

489 {
490 /*
491 * When you're moving forward in the search and you hit an axiom,
492 * you need to see whether there are right branches still needing
493 * to be dealt with.
494 *
495 * Note that an empty right_branch_stack - meaning that you've
496 * found a proof - is dealt with by go().
497 *
498 * this_action does not get populated for the new StackItem in
499 * this case.
500 */
501 right_branches_started++;
502 /*
503 * Move the next right branch to the stack.
504 */
505 stack.push_back(right_branch_stack.back());
506 right_branch_stack.pop_back();
507 /*
508 * Reset si.
509 */
510 si++;
511 /*
512 * Set up the new state.
513 */
514 new_C = stack[si].c;
515 path = stack[si].p;
516 lemmata = stack[si].l;
517 current_depth = stack[si].depth;
518 /*
519 * We deliberately delayed doing this, so do it now. (See
520 * documentation for StackProver::extend_with_action.)
521 */
522 populate_stack_item();
523 /*
524 * At this point you are starting a right branch, so
525 * if you are restricting backtracking you remove all
526 * alternatives from the relevant point in the stack.
527 */
528 if (params::limit_bt_extensions) {
529 stack[stack[si].bt_restriction_index].restrict_backtrack();
530 }
531}
Stack::push_back
void push_back(const StackItem &_item)
Exact analogue of the same function for vector<>.
Definition Stack.hpp:100

◆ prove()

ProverOutcome StackProver::prove ( )

Here is where the magic happens.

You should only need to load the problem and call this method.

Make sure you deal with reordering.

Definition at line 1028 of file StackProver.cpp.

1028 {
1032 if (params::deterministic_reorder) {
1033 deterministic_reorder(params::number_of_reorders);
1034 }
1035 if (params::random_reorder) {
1036 random_reorder();
1037 }
1038 if (params::random_reorder_literals) {
1039 random_reorder_literals();
1040 }
1041 pair<bool, size_t> start_clause = matrix.find_start();
1042 /*
1043 * If the initial clauses don't have a positive and a negative
1044 * clause then the problem is trivial.
1045 */
1046 if (!start_clause.first) {
1047 return ProverOutcome::False;
1048 }
1049 /*
1050 * You now have a complete matrix and you know its size.
1051 * This means you can set up caching of clause copies
1052 * properly.
1053 */
1054 clause_cache.set_size(matrix.get_num_clauses());
1055 clause_cache.reset(matrix, var_index, term_index);
1056 /*
1057 * Deal with the possible ways to set up start clause(s) according to
1058 * the options. Keep track of which start clauses are in use, and if
1059 * necessary what outcomes for them have been seen so far.
1060 */
1061 set_up_start_clauses();
1062 /*
1063 * Main loop for iterative deepening search.
1064 */
1065 bool switched_to_complete = false;
1066 for (current_depth_limit = params::start_depth;
1067 current_depth_limit <= params::depth_limit;
1068 current_depth_limit += params::depth_increment) {
1069 /*
1070 * See if the parameters dictate that it's time to convert to
1071 * a complete search.
1072 */
1073 if (current_depth_limit >= params::switch_to_complete
1074 && !switched_to_complete) {
1075 params::set_complete_parameters();
1076 /*
1077 * You may have changed some parameters, so make sure all relevant
1078 * start clauses now get tried.
1079 */
1080 set_up_start_clauses();
1081 current_depth_limit = params::start_depth;
1082 switched_to_complete = true;
1083 colour_string::ColourString cs(params::use_colours);
1084 show.nl(1);
1085 show(1, cs("Switching to complete search.").orange(), true);
1086 }
1087 show.nl(1);
1088 show(1, string("SEARCH TO DEPTH: "));
1089 show(1, std::to_string(current_depth_limit), true);
1090 /*
1091 * Generate each possible start move, and try to prove from
1092 * it.
1093 */
1094 size_t start_clause_index = 0;
1095 for (const Clause& C : matrix) {
1096 /*
1097 * Find the next start clause.
1098 */
1099 if (results[start_clause_index] == StartClauseStatus::NoStart
1100 || results[start_clause_index] == StartClauseStatus::False) {
1101 start_clause_index++;
1102 continue;
1103 }
1104 /*
1105 * Reset everything to use the current start clause.
1106 *
1107 * TODO: this is slightly messy at present because
1108 * the var_index doesn't necessarily get reset in the
1109 * most efficient way possible if a previous schedule
1110 * attempt timed out. (You'd need to go back down
1111 * the stack and backtrack it as necessary.) This is
1112 * of course irrelevant
1113 * because it just means you might not get full re-use of
1114 * new variable names, but all the same it would be nice
1115 * to fix.
1116 */
1117 //var_index.add_backtrack_point();
1118 clause_cache.make_copy_with_new_variables(start_clause_index, new_C, matrix, var_index, term_index);
1119 //new_C = C.make_copy_with_new_vars(var_index, term_index);
1120 reset_for_start();
1121 /*
1122 * Say what's going on.
1123 */
1124 show(1, string("START from clause "));
1125 show(1, std::to_string(start_clause_index + 1));
1126 show(1, string(" of "));
1127 show(1, std::to_string(matrix.get_num_clauses()));
1128 show(2, string(": "));
1129 show(2, new_C.to_string(), true);
1130 cout.flush();
1131 /*
1132 * Set up the initial stack item containing the start clause, and
1133 * populate it.
1134 */
1135 StackItem start_item(StackItemType::Start, new_C, path, lemmata, 1);
1136 start_item.set_this_action(InferenceItem(InferenceItemType::Start, start_clause_index));
1137 stack.push_back(start_item);
1138 si = 0;
1139 populate_stack_item();
1140 /*
1141 * Start with depth 1, as this makes sense when reading output if you're
1142 * using depth of recursion or path length.
1143 */
1144 current_depth = 1;
1145 /*
1146 * Liftoff!!!
1147 */
1148 ProverResult result = go();
1149 /*
1150 * Dealing with the outcome takes some care and depends on
1151 * the parameters being used.
1152 */
1153 switch (result) {
1154 case ProverResult::Valid:
1155 proof_count++;
1156 if (params::build_proof) {
1157 if (params::generate_LaTeX_proof) {
1158 proof_printer.make_LaTeX(params::LaTeX_proof_path,
1159 problem_path,
1160 matrix.make_LaTeX());
1161 }
1162 if (params::generate_LaTeX_tableau_proof) {
1163 proof_printer.make_LaTeX_connection_tableau(params::LaTeX_tableau_proof_path,
1164 problem_path,
1165 matrix.make_LaTeX());
1166 }
1167 if (params::generate_Prolog_proof) {
1168 fs::path prolog_path = params::Prolog_proof_path;
1169 proof_printer.make_Prolog(prolog_path);
1170 matrix.write_to_prolog_file(params::Prolog_matrix_path);
1171 }
1172 }
1173 show(1, string(": Found proof number "));
1174 show(1, std::to_string(proof_count), true);
1175 return ProverOutcome::Valid;
1176 break;
1177 case ProverResult::Error:
1178 return ProverOutcome::Error;
1179 break;
1180 case ProverResult::TimeOut:
1181 return ProverOutcome::TimeOut;
1182 break;
1183 case ProverResult::OptionsExhausted:
1184 /*
1185 * If you ran out of options because you reached the depth
1186 * limit then you still need to continue.
1187 */
1188 if (depth_limit_reached) {
1189 show(1, string(": Depth limited"), true);
1190 }
1191 /*
1192 * If you ran out of options without reaching the depth limit, then
1193 * what you do depends on whether or not the search is complete.
1194 */
1195 else {
1196 if (params::search_is_complete()) {
1197 results[start_clause_index] = StartClauseStatus::False;
1198 show(1, string(": False"), true);
1199 }
1200 }
1201 start_clause_index++;
1202 break;
1203 default:
1204 return ProverOutcome::Error;
1205 break;
1206 }
1207 /*
1208 * This is necessary. Yes, I've checked. Think about it: you need
1209 * one extra backtrack to undo the new variables generated when you
1210 * make a start clause.
1211 */
1212 clause_cache.backtrack();
1213 //var_index.backtrack();
1214 }
1215 /*
1216 * Loop for start moves ends here.
1217 *
1218 * If everything was False then the theorem is False, otherwise
1219 * at least one attempt was depth-limited.
1220 */
1221 bool all_false = true;
1222 for (StartClauseStatus& outcome : results) {
1223 if (outcome == StartClauseStatus::Start) {
1224 all_false = false;
1225 break;
1226 }
1227 }
1228 if (all_false)
1229 return ProverOutcome::False;
1230 }
1231 /*
1232 * Iterative deepening loop ends here.
1233 */
1234 return ProverOutcome::PathLenLimit;
1235}
ClauseCopyCache::set_size
void set_size(size_t _s)
Set the number of clauses we need cached copies for.
Definition ClauseCopyCache.hpp:85
ClauseCopyCache::reset
void reset(const Matrix &, VariableIndex &, TermIndex &)
This is for any actual initialisation, when you either (1) intially know what you're dealing with,...
Definition ClauseCopyCache.cpp:28
Clause::to_string
string to_string(bool=false) const
Convert to a string.
Definition Clause.cpp:257
Matrix::get_num_clauses
ClauseNum get_num_clauses() const
Straightforward get method.
Definition Matrix.hpp:225
Matrix::make_LaTeX
string make_LaTeX(bool=false) const
Make a usable LaTeX representation.
Definition Matrix.cpp:259
Matrix::write_to_prolog_file
void write_to_prolog_file(const path &) const
Write to a file that can be read by Prolog.
Definition Matrix.cpp:274
Matrix::find_start
pair< bool, size_t > find_start() const
Use a simple heuristic to find a good start clause.
Definition Matrix.cpp:54
ProofPrinter::make_LaTeX_connection_tableau
void make_LaTeX_connection_tableau(const path &, const path &, const string &)
Convert to LaTeX in the connection tableau calculus and store in the specified file.
Definition ProofPrinter.cpp:170
ProofPrinter::make_Prolog
void make_Prolog(const path &)
Convert to a form suitable for use by the Prolog proof checker and write to a file.
Definition ProofPrinter.cpp:228
ProofPrinter::make_LaTeX
void make_LaTeX(const path &, const path &, const string &)
Convert to LaTeX and store in the specified file.
Definition ProofPrinter.cpp:118
StackProver::reset_for_start
void reset_for_start()
Reset everything so that you can start from a specified start clause.
Definition StackProver.hpp:310
StackProver::random_reorder
void random_reorder()
Randomly reorder the matrix.
Definition StackProver.hpp:433
StackProver::set_up_start_clauses
void set_up_start_clauses()
The start clauses to use depend on the settings, and the settings can change.
Definition StackProver.cpp:901
StackProver::go
ProverResult go()
This runs the proof search from a given Start Move.
Definition StackProver.cpp:640
StackProver::deterministic_reorder
void deterministic_reorder(uint32_t n)
Deterministically reorder the matrix n times.
Definition StackProver.hpp:427
StackProver::random_reorder_literals
void random_reorder_literals()
Randomly reorder the literals in each clause in the matrix.
Definition StackProver.hpp:440
colour_string::ColourString
Simple addition of colour to strings and ostreams.
Definition vic_strings.hpp:121
verbose_print::VPrint::nl
void nl(uint8_t, uint8_t=1)
Definition vic_strings.cpp:142
InferenceItem
Full representation of inferences, beyond just the name.
Definition InferenceItem.hpp:61
StackItem
Stack items: each contains its own material for generating possible next inferences.
Definition StackItem.hpp:54
params::set_complete_parameters
static void set_complete_parameters()
Change the parameters to make the search complete.
Definition Parameters.cpp:222
params::search_is_complete
static bool search_is_complete()
Self-explanatory.
Definition Parameters.cpp:234

◆ random_reorder()

void StackProver::random_reorder ( )
inline

Randomly reorder the matrix.

Definition at line 433 of file StackProver.hpp.

433 {
434 matrix.random_reorder();
435 }
Matrix::random_reorder
void random_reorder()
Randomly reorder the matrix.
Definition Matrix.cpp:164

◆ random_reorder_literals()

void StackProver::random_reorder_literals ( )
inline

Randomly reorder the literals in each clause in the matrix.

Definition at line 440 of file StackProver.hpp.

440 {
441 matrix.random_reorder_literals();
442 }
Matrix::random_reorder_literals
void random_reorder_literals()
Randomly reorder the literals in each clause in the matrix.
Definition Matrix.cpp:190

◆ read_from_tptp_file()

void StackProver::read_from_tptp_file ( const string & file_name,
bool & found_conjecture,
size_t & fof_size )

Obviously, reads a problem from a TPTP file.

Does pretty much all of the setup required.

Parameters
file_nameName of the file to use.
found_conjectureUsed to indicate whether a conjecture is found in the problem.
fof_sizeNumber of first-order formulas found.

Definition at line 79 of file StackProver.cpp.

81 {
82 TPTPParser parser(&var_index, &fun_index, &term_index, &pred_index, &matrix);
83 parser.parse_tptp_from_file(file_name);
84 status = parser.get_problem_status();
85 bool equality = parser.equality_used();
86 found_conjecture = parser.conjecture_present();
87 fof_size = parser.number_of_fof_formulas();
88 Predicate* equals_predicate = parser.get_equals_predicate();
89 cnf_only = parser.problem_is_cnf_only();
90 conjecture_true = parser.fof_conjecture_is_true();
91 conjecture_false = parser.fof_conjecture_is_false();
92 conjecture_missing = parser.fof_conjecture_is_missing();
93 negated_conjecture_removed = parser.fof_negated_conjecture_removed();
94 fof_has_axioms = parser.fof_has_axioms();
95 simplified_fof_has_axioms = parser.simplified_fof_has_axioms();
96 tptp_conversion_string = parser.get_tptp_conversion_string();
97 parser.clear();
98 num_preds = pred_index.get_num_preds();
99 /*
100 * num_preds for Matrix is set by parser.
101 */
102 path.set_num_preds(num_preds);
103
104 if (params::show_clauses) {
105 std::exit(EXIT_SUCCESS);
106 }
107
108 if (status != string("") && params::first_parse) {
109 show(1, string("Problem status found: "));
110 show(1, status, true);
111 }
112 if (equality && params::add_equality_axioms) {
113 if (params::first_parse) {
114 show(1, string("Problem involves equality: adding axioms for =."), true);
115 params::first_parse = false;
116 }
117 add_equality_axioms(equals_predicate);
118 if (params::equality_axioms_at_start) {
119 matrix.move_equals_to_start();
120 }
121 }
122 /*
123 * Any further variables will be anonymous.
124 */
125 var_index.set_all_names_added();
126 }
Matrix::move_equals_to_start
void move_equals_to_start()
Self-explanatory.
Definition Matrix.cpp:208
StackProver::add_equality_axioms
void add_equality_axioms(Predicate *)
After reading a problem in which = and/or != appears, add the axioms for equality.
Definition StackProver.cpp:128
TPTPParser
Wrap up everything the TPTP parser needs to do inside a single class.
Definition TPTPParser.hpp:659
VariableIndex::set_all_names_added
void set_all_names_added()
Call this to indicate that only anonymous variables can now be created.
Definition VariableIndex.cpp:66

◆ reduction_backtrack()

void StackProver::reduction_backtrack ( )
private

One of several different kinds of backtracking.

Definition at line 540 of file StackProver.cpp.

540 {
541 sub_stack.backtrack();
542 backtrack_once();
543}

◆ reset_for_start()

void StackProver::reset_for_start ( )
inlineprivate

Reset everything so that you can start from a specified start clause.

Definition at line 310 of file StackProver.hpp.

310 {
311 depth_limit_reached = false;
312 si = 0;
313 backtrack = false;
314 path.clear();
315 stack.clear();
316 lemmata.clear();
317 right_branch_stack.clear();
318 sub_stack.clear();
319 }
Lemmata::clear
void clear()
Self-explanatory.
Definition Lemmata.hpp:74
Stack::clear
void clear()
Exact analogue of the same function for vector<>.
Definition Stack.hpp:82
SubstitutionStack::clear
void clear()
Reset everything.
Definition SubstitutionStack.hpp:91

◆ right_extension_backtrack()

void StackProver::right_extension_backtrack ( )
private

One of several different kinds of backtracking.

Here be DRAGONS.

Care needed here. If the state is a right branch, then it may or may not have to go back on right_branch_stack as you may or may not need to try it again, depending on the settings.

If you get this wrong you get a REALLY evil bug, because with the standard restricted backtracking you put it back on the stack when it's not needed. You then end up with extra things in the proof certificate which invalidate it, even though you can take them out and possibly get something valid.

Guess how I know this!

Definition at line 578 of file StackProver.cpp.

578 {
579 /*
580 * If you're not limiting backtracking for extensions, or
581 * you *are*, but you're still exploring left trees, then this
582 * is straightforward: just put the item back on right_branch_stack
583 * so that it gets explored again later.
584 */
585 if (!params::limit_bt_extensions ||
586 ((params::limit_bt_extensions || params::limit_bt_all) &&
587 !params::limit_bt_extensions_left_tree)) {
588 /*
589 * Why is this necessary? After we backtrack we may make different
590 * substitutions, so in revisiting the right branch different
591 * possibilties may apply, so we re-compute them later.
592 */
593 right_branch_stack.push_back(stack.back());
594 backtrack_once();
595 return;
596 }
597 /*
598 * We know we are limiting backtracking for extensions, and we
599 * are not exploring the left tree.
600 *
601 * Care is needed if you're not backtracking within the left
602 * part of the tree. You need to move back down the stack,
603 * deleting everything while also making sure that sub_stack
604 * and var_index are correctly maintained. Also, you don't
605 * want to return anything to right_branch_stack.
606 *
607 * This goes back to where the relevant literal was selected.
608 * Thus if you are not limiting the possibilities to only those
609 * for the first literal, it's open to the backtracking
610 * restriction to leave other possibilites to be tried, and
611 * they get picked up from this point.
612 */
613 if (params::limit_bt_extensions_left_tree) {
614 size_t target_index = stack[si].bt_restriction_index;
615 size_t current_index = stack.size() - 1;
616 while (current_index > target_index) {
617 switch (stack[si].item_type) {
618 case StackItemType::Lemmata:
619 break;
620 case StackItemType::Reduction:
621 sub_stack.backtrack();
622 break;
623 case StackItemType::LeftBranch:
624 //var_index.backtrack();
625 clause_cache.backtrack();
626 sub_stack.backtrack();
627 break;
628 case StackItemType::RightBranch:
629 break;
630 default:
631 cerr << "Something is VERY WRONG!" << endl;
632 break;
633 }
634 backtrack_once();
635 current_index--;
636 }
637 }
638}

◆ set_num_preds()

void StackProver::set_num_preds ( size_t n)

Set the number of predicates.

But don't! You should never need to do this.

Definition at line 73 of file StackProver.cpp.

73 {
74 num_preds = n;
75 matrix.set_num_preds(n);
76 path.set_num_preds(n);
77}
Matrix::set_num_preds
void set_num_preds(size_t)
Make an empty index.
Definition Matrix.cpp:44

◆ set_problem_path()

void StackProver::set_problem_path ( fs::path & p)
inline

Set the path for the problem being solved.

Used only to produce nice output.

Definition at line 394 of file StackProver.hpp.

394{ problem_path = p; }

◆ set_timeout()

void StackProver::set_timeout ( chrono::steady_clock::time_point time)
inline

Set a timeout.

A StackProver is always constructed to have no timeout. This sets a timeout to use in seconds. The parameters are separate from the params::???? values as the latter apply globally whereas these allow for schedules to be constructed.

Parameters
timethe time to stop: you will need to know about the standard library!

Definition at line 385 of file StackProver.hpp.

385 {
386 use_timeout = true;
387 end_time = time;
388 }

◆ set_up_start_clauses()

void StackProver::set_up_start_clauses ( )
private

The start clauses to use depend on the settings, and the settings can change.

Definition at line 901 of file StackProver.cpp.

901 {
902 results.clear();
903 size_t m_size = matrix.get_num_clauses();
904 /*
905 * Make sure noone has messed up and not set any start
906 * clause optionss.
907 */
908 if (params::no_start_options())
909 params::correct_missing_start_options();
910 /*
911 * The allstart option overides everything else so this is easy.
912 */
913 if (params::all_start) {
914 for (size_t i = 0; i < m_size; i++) {
915 results.push_back(StartClauseStatus::Start);
916 }
917 return;
918 }
919 bool first_clause_included = false;
920 /*
921 * params::all_pos_neg_start indicates use of positive
922 * or negative start clauses according to the representation.
923 * When you don't also have conjecture_start, either include
924 * all, or just the first possibility found.
925 */
926 if (params::all_pos_neg_start && !params::conjecture_start) {
927 for (size_t i = 0; i < m_size; i++) {
928 if (
929 (
930 (params::positive_representation && matrix.is_positive(i))
931 ||
932 (!params::positive_representation && matrix.is_negative(i))
933 )
934 &&
935 (!(params::restrict_start && first_clause_included))
936 ) {
937 results.push_back(StartClauseStatus::Start);
938 first_clause_included = true;
939 }
940 else {
941 results.push_back(StartClauseStatus::NoStart);
942 }
943 }
944 }
945 /*
946 * Similar case if you have conjecture_start but not all_pos_neg_start.
947 */
948 else if (!params::all_pos_neg_start && params::conjecture_start) {
949 for (size_t i = 0; i < m_size; i++) {
950 if (matrix.is_conjecture(i)
951 &&
952 (!(params::restrict_start && first_clause_included))) {
953 results.push_back(StartClauseStatus::Start);
954 first_clause_included = true;
955 }
956 else {
957 results.push_back(StartClauseStatus::NoStart);
958 }
959 }
960 }
961 /*
962 * The tricky case is when you want to combine pos/neg clauses,
963 * conjecture clauses, and restriction in some other way.
964 *
965 * Assume here that you have all_pos_neg_start and conjecture_start.
966 */
967 else {
968 for (size_t i = 0; i < m_size; i++) {
969 if (matrix.is_conjecture(i)
970 &&
971 (
972 (params::positive_representation && matrix.is_positive(i))
973 ||
974 (!params::positive_representation && matrix.is_negative(i))
975 )
976 &&
977 !(params::restrict_start && first_clause_included)) {
978 results.push_back(StartClauseStatus::Start);
979 first_clause_included = true;
980 }
981 else {
982 results.push_back(StartClauseStatus::NoStart);
983 }
984 }
985 }
986 /*
987 * There's a rare possibility that---because either there was no
988 * (negated) conjecture clause in the problem, or they were
989 * simplified out---at this point no start clause has been
990 * selected. If that's the case, either use all positive/negative
991 * clauses or just the first, according to the parameters set.
992 *
993 * Note: this must choose at least one start clause because problems
994 * without a positive and negative clause have already been solved.
995 */
996 if (!first_clause_included) {
997 if (params::verbosity > 2) {
998 cout << "Note: you're asking for a conjecture to start, but there are none!" << endl;
999 cout << " depending on the other parameter settings, we will use one or " << endl;
1000 cout << " all of the negative clauses." << endl;
1001 }
1002 // Don't forget this! If you get here you have a whole bunch of
1003 // NoStart in results!
1004 results.clear();
1005 for (size_t i = 0; i < m_size; i++) {
1006 if ((
1007 (params::positive_representation && matrix.is_positive(i))
1008 ||
1009 (!params::positive_representation && matrix.is_negative(i))
1010 ) &&
1011 !(params::restrict_start && first_clause_included)) {
1012 results.push_back(StartClauseStatus::Start);
1013 first_clause_included = true;
1014 }
1015 else {
1016 results.push_back(StartClauseStatus::NoStart);
1017 }
1018 }
1019 }
1020}
Matrix::is_negative
bool is_negative(size_t i) const
Is a particular Clause negative?
Definition Matrix.hpp:279
Matrix::is_conjecture
bool is_conjecture(size_t i) const
Is a particular Clause a conjecture?
Definition Matrix.cpp:49
Matrix::is_positive
bool is_positive(size_t i) const
Is a particular Clause positive?
Definition Matrix.hpp:273
params::no_start_options
static bool no_start_options()
Self-explanatory.
Definition Parameters.cpp:254
params::correct_missing_start_options
static void correct_missing_start_options()
Self-explanatory.
Definition Parameters.cpp:261

◆ show_full_statistics()

void StackProver::show_full_statistics ( size_t ms) const

Display counts of number of extensions tried and so on, as well as numbers per second.

Definition at line 1269 of file StackProver.cpp.

1269 {
1270 size_t total = reductions_tried + extensions_tried + lemmata_tried + right_branches_started;
1271 double s = static_cast<double>(ms) / 1000.0;
1272 double ext_rate = (static_cast<double>(extensions_tried) / s);
1273 double red_rate = (static_cast<double>(reductions_tried) / s);
1274 double lem_rate = (static_cast<double>(lemmata_tried) / s);
1275 double right_rate = (static_cast<double>(right_branches_started) / s);
1276 double total_rate = (static_cast<double>(total) / s);
1277 cout << "Reductions: " << setw(15) << reductions_tried << " (" << static_cast<size_t>(red_rate) << "/s)" << endl;
1278 cout << "Extensions: " << setw(15) << extensions_tried << " (" << static_cast<size_t>(ext_rate) << "/s)" << endl;
1279 cout << "Lemmas: " << setw(15) << lemmata_tried << " (" << static_cast<size_t>(lem_rate) << "/s)" << endl;
1280 cout << "Right branches: " << setw(15) << right_branches_started << " (" << static_cast<size_t>(right_rate) << "/s)" << endl;
1281 cout << "Total: " << setw(15) << total << " (" << static_cast<size_t>(total_rate) << "/s)" << endl;
1282}

◆ show_matrix() [1/2]

void StackProver::show_matrix ( )
inline

Show a nicely formatted matrix.

Definition at line 446 of file StackProver.hpp.

446 {
447 cout << "Matrix:" << endl;
448 cout << matrix.to_string() << endl;
449 }
Matrix::to_string
string to_string() const
Make a string representation.
Definition Matrix.cpp:236

◆ show_matrix() [2/2]

void StackProver::show_matrix ( ) const
inline

Definition at line 543 of file StackProver.hpp.

543{ cout << matrix << endl; }

◆ show_path()

void StackProver::show_path ( ) const
inline

Definition at line 544 of file StackProver.hpp.

544{ cout << path << endl; }

◆ show_right_stack()

void StackProver::show_right_stack ( )

Definition at line 1249 of file StackProver.cpp.

1249 {
1250 cout << "--------------------------------------------------------" << endl;
1251 cout << "Right Stack:" << endl;
1252 cout << "--------------------------------------------------------" << endl;
1253 cout << right_branch_stack << endl;
1254 cout << "--------------------------------------------------------" << endl;
1255}

◆ show_stack()

void StackProver::show_stack ( )

Definition at line 1241 of file StackProver.cpp.

1241 {
1242 cout << "--------------------------------------------------------" << endl;
1243 cout << "Stack:" << endl;
1244 cout << "--------------------------------------------------------" << endl;
1245 cout << stack << endl;
1246 cout << "--------------------------------------------------------" << endl;
1247}

◆ show_statistics()

void StackProver::show_statistics ( ) const

Display counts of number of extensions tried and so on.

Definition at line 1257 of file StackProver.cpp.

1257 {
1258 verbose_print::VPrint show(params::verbosity);
1259 show(1, string("Reductions: "));
1260 show(1, std::to_string(reductions_tried));
1261 show(1, string(" Extensions: "));
1262 show(1, std::to_string(extensions_tried));
1263 show(1, string(" Lemmata: "));
1264 show(1, std::to_string(lemmata_tried));
1265 show(1, string(" Right branches: "));
1266 show(1, std::to_string(right_branches_started), true);
1267}
verbose_print::VPrint
Definition vic_strings.hpp:240

◆ show_term_index()

void StackProver::show_term_index ( )
inline

Definition at line 547 of file StackProver.hpp.

547{ cout << term_index << endl; }

◆ show_tptp_proof()

void StackProver::show_tptp_proof ( )
inline

Show a Prolog-formatted proof.

Definition at line 512 of file StackProver.hpp.

512 {
513 cout << endl << "% Problem matrix:" << endl;
514 matrix.show_tptp();
515 cout << endl << "% Proof stack:" << endl;
516 proof_printer.show_tptp();
517 }
Matrix::show_tptp
void show_tptp() const
Output in TPTP compatible format.
Definition Matrix.cpp:291
ProofPrinter::show_tptp
void show_tptp()
Show the proof in a TPTP-friendly format.
Definition ProofPrinter.cpp:344

◆ simplified_problem_has_fof_axioms()

bool StackProver::simplified_problem_has_fof_axioms ( ) const
inline

Find out from the parser whether the problem had axioms after simplification.

Definition at line 503 of file StackProver.hpp.

503 {
504 return simplified_fof_has_axioms;
505 }

Friends And Related Symbol Documentation

◆ operator<<

ostream & operator<< ( ostream & out,
const StackProver & p )
friend

Definition at line 1284 of file StackProver.cpp.

1284 {
1285 out << "Current state of the RecursiveProver object" << endl;
1286 out << "-------------------------------------------" << endl << endl;
1287 out << p.var_index << endl;
1288 out << p.fun_index << endl;
1289 out << p.term_index << endl;
1290 out << p.path << endl;
1291 out << p.matrix << endl;
1292 return out;
1293}

Member Data Documentation

◆ action

InferenceItem StackProver::action
private

Stores the next action from the current StackItem.

Definition at line 153 of file StackProver.hpp.

◆ backtrack

bool StackProver::backtrack
private

Are we moving up or down the stack?

Definition at line 192 of file StackProver.hpp.

◆ clause_cache

ClauseCopyCache StackProver::clause_cache
private

Manages caching of copies of clauses from the matrix.

Definition at line 127 of file StackProver.hpp.

◆ cnf_only

bool StackProver::cnf_only
private

Keep track of whether there were any FOF formulas in the problem file.

Definition at line 324 of file StackProver.hpp.

◆ conjecture_false

bool StackProver::conjecture_false
private

Keep track of whether the parser found the conjecture to be false.

Definition at line 332 of file StackProver.hpp.

◆ conjecture_missing

bool StackProver::conjecture_missing
private

Keep track of whether the parser found a conjecture in the problem file.

Definition at line 336 of file StackProver.hpp.

◆ conjecture_true

bool StackProver::conjecture_true
private

Keep track of whether the parser found the conjecture to be true.

Definition at line 328 of file StackProver.hpp.

◆ current_depth

uint32_t StackProver::current_depth
private

Self-explanatary.

Definition at line 165 of file StackProver.hpp.

◆ current_depth_limit

uint32_t StackProver::current_depth_limit
private

Self-explanatary.

Definition at line 161 of file StackProver.hpp.

◆ depth_limit_reached

bool StackProver::depth_limit_reached
private

Self-explanatary.

Definition at line 169 of file StackProver.hpp.

◆ end_time

chrono::steady_clock::time_point StackProver::end_time
private

When do we stop because of a timeout?

Definition at line 241 of file StackProver.hpp.

◆ extensions_tried

uint32_t StackProver::extensions_tried = 0
staticprivate

We'll be keeping some simple statistics about the search process.

Definition at line 218 of file StackProver.hpp.

◆ fof_has_axioms

bool StackProver::fof_has_axioms
private

Keep track of whether the parser found that it's an FOF problem with axioms before simplification.

Definition at line 345 of file StackProver.hpp.

◆ fun_index

FunctionIndex StackProver::fun_index
private

This class needs one of each kind of index to keep track of Variables, Terms etc.

Definition at line 92 of file StackProver.hpp.

◆ lemmata

Lemmata StackProver::lemmata
private

At any point in the search process this is a copy of the list of lemmas for the current node in the proof being constructed.

Definition at line 145 of file StackProver.hpp.

◆ lemmata_tried

uint32_t StackProver::lemmata_tried = 0
staticprivate

We'll be keeping some simple statistics about the search process.

Definition at line 223 of file StackProver.hpp.

◆ matrix

Matrix StackProver::matrix
private

A copy of the matrix you're working with.

Definition at line 122 of file StackProver.hpp.

◆ negated_conjecture_removed

bool StackProver::negated_conjecture_removed
private

Keep track of whether the parser simplified the conjecture away.

Definition at line 340 of file StackProver.hpp.

◆ new_C

Clause StackProver::new_C
private

At any point in the search process this is a copy of the clause for the current node in the proof being constructed.

Definition at line 139 of file StackProver.hpp.

◆ num_preds

size_t StackProver::num_preds
private

How many prdicates does the problem of interest have?

Definition at line 82 of file StackProver.hpp.

◆ output_interval

Interval StackProver::output_interval
private

How often do you output updates about progress?

Definition at line 205 of file StackProver.hpp.

◆ path

SimplePath StackProver::path
private

At any point in the search process this is a copy of the path for the current node in the proof being constructed.

Definition at line 133 of file StackProver.hpp.

◆ pred_index

PredicateIndex StackProver::pred_index
private

This class needs one of each kind of index to keep track of Variables, Terms etc.

Definition at line 102 of file StackProver.hpp.

◆ problem_path

fs::path StackProver::problem_path
private

Path for the problem of interest.

Definition at line 201 of file StackProver.hpp.

◆ proof_count

uint32_t StackProver::proof_count
private

If we're searching for multiple proofs, keep count
of which one this is.

Definition at line 233 of file StackProver.hpp.

◆ proof_printer

ProofPrinter StackProver::proof_printer
private

You need one of these to print LaTeX output or any kind of proof certificate.

Definition at line 197 of file StackProver.hpp.

◆ reductions_tried

uint32_t StackProver::reductions_tried = 0
staticprivate

We'll be keeping some simple statistics about the search process.

Note that at present these statistics include everything tried over all steps in a schedule.

Definition at line 213 of file StackProver.hpp.

◆ results

vector<StartClauseStatus> StackProver::results
private

This is populated by the StackProver::set_up_start_clauses method.

That method looks at the settings for start clauses and tries to achieve them all in a sensible way. Initially this indicates which clauses to use to start, but then stores the results obtained after trying each possibility.

Definition at line 118 of file StackProver.hpp.

◆ right_branch_stack

Stack StackProver::right_branch_stack
private

We build the proof by trying the left branches of extensions first: this stack keeps track of the right branches that we need to come back to.

Definition at line 188 of file StackProver.hpp.

◆ right_branches_started

uint32_t StackProver::right_branches_started = 0
staticprivate

We'll be keeping some simple statistics about the search process.

Definition at line 228 of file StackProver.hpp.

◆ show

verbose_print::VPrint StackProver::show
private

Set up printing according to verbosity.

Definition at line 245 of file StackProver.hpp.

◆ si

size_t StackProver::si
private

Index of the current StackItem.

Definition at line 157 of file StackProver.hpp.

◆ simplified_fof_has_axioms

bool StackProver::simplified_fof_has_axioms
private

Keep track of whether the parser found that it's an FOF problem with axioms after simplification.

Definition at line 350 of file StackProver.hpp.

◆ stack

Stack StackProver::stack
private

Main stack: this is constructed by the search process and, if completed, represents a proof.

Definition at line 182 of file StackProver.hpp.

◆ status

string StackProver::status
private

Problem status, if found in input file.

Definition at line 173 of file StackProver.hpp.

◆ sub_stack

SubstitutionStack StackProver::sub_stack
private

There is a separate stack to make application and removal of substitutions straightforward.

Definition at line 107 of file StackProver.hpp.

◆ term_index

TermIndex StackProver::term_index
private

This class needs one of each kind of index to keep track of Variables, Terms etc.

Definition at line 97 of file StackProver.hpp.

◆ tptp_conversion_string

string StackProver::tptp_conversion_string
private

TPTP-friendly description of the clause conversion.

Definition at line 177 of file StackProver.hpp.

◆ u

Unifier StackProver::u
private

We need a single Unifier to use throughout the process.

Definition at line 149 of file StackProver.hpp.

◆ use_timeout

bool StackProver::use_timeout
private

Are we using a timeout?

Definition at line 237 of file StackProver.hpp.

◆ var_index

VariableIndex StackProver::var_index
private

This class needs one of each kind of index to keep track of Variables, Terms etc.

Definition at line 87 of file StackProver.hpp.

The documentation for this class was generated from the following files: