Awali
Another Weighted Automata library
maxmin.hh
Go to the documentation of this file.
1 // This file is part of Awali.
2 // Copyright 2016-2021 Sylvain Lombardy, Victor Marsault, Jacques Sakarovitch
3 //
4 // Awali is a free software: you can redistribute it and/or modify
5 // it under the terms of the GNU General Public License as published by
6 // the Free Software Foundation, either version 3 of the License, or
7 // (at your option) any later version.
8 //
9 // This program is distributed in the hope that it will be useful,
10 // but WITHOUT ANY WARRANTY; without even the implied warranty of
11 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
12 // GNU General Public License for more details.
13 //
14 // You should have received a copy of the GNU General Public License
15 // along with this program. If not, see <http://www.gnu.org/licenses/>.
16 
17 #ifndef AWALI_WEIGHTSET_MAXMIN_HH
18 # define AWALI_WEIGHTSET_MAXMIN_HH
19 
20 # include <ostream>
21 # include <string>
22 # include <sstream>
23 # include <utility>
24 
25 #include <awali/sttc/misc/raise.hh>
26 #include <awali/common/enums.hh>
27 # include <limits>
28 #include <awali/sttc/misc/stream.hh> // eat
33 
34 namespace awali {
35  namespace sttc {
41  class maxmin
42  {
43  public:
44  using self_type = maxmin;
45 
46  static std::string sname()
47  {
48  return "maxmin";
49  }
50 
51  std::string vname(bool = true) const
52  {
53  return sname();
54  }
55 
57  static maxmin make(std::istream& is)
58  {
59  eat(is, sname());
60  return {};
61  }
62 
63  using value_t = double;
64  using locally_finite_t = bool;
65  static const locally_finite_t locally_finite=true;
66 
67  static value_t
68  add(const value_t l, const value_t r)
69  {
70  return std::max(l, r);
71  }
72 
73  static value_t
74  mul(const value_t l, const value_t r)
75  {
76  return std::min(l, r);
77  }
78 
79  static value_t
80  rdiv(const value_t l, const value_t r)
81  {
82  raise(sname(), "No division");
83  }
84 
85  static value_t
86  ldiv(const value_t l, const value_t r)
87  {
88  raise(sname(), "No division");
89  }
90 
91  value_t
92  star(const value_t v) const
93  {
94  return one();
95  }
96 
97  static value_t
98  one()
99  {
101  }
102 
103  static value_t
105  {
107  }
108 
109  static bool
110  equals(const value_t l, const value_t r)
111  {
112  return l == r;
113  }
114 
116  static bool less_than(value_t lhs, value_t rhs)
117  {
118  return lhs < rhs;
119  }
120 
121  constexpr static bool is_special(value_t)
122  {
123  return false;
124  }
125 
126  static bool
127  is_zero(const value_t v)
128  {
129  return v == zero();
130  }
131 
132  static bool
133  is_one(const value_t v)
134  {
135  return v == one();
136  }
137 
138  static constexpr bool is_commutative_semiring() { return true; }
139 
140  static constexpr bool show_one() { return true; }
141  static constexpr star_status_t star_status() { return star_status_t::STARRABLE; }
142 
143  static value_t
145  {
146  return v;
147  }
148 
149  static size_t hash(value_t v)
150  {
151  return utils::hash_value(v);
152  }
153 
154  static value_t
156  {
157  return v;
158  }
159 
160  static value_t
162  {
163  return v ? one() : zero();
164  }
165 
166  static value_t
167  conv(std::istream& stream)
168  {
169  switch (int i = stream.peek())
170  {
171  case 'o':
172  stream.ignore();
173  if ((i = stream.get()) == 'o')
174  return one();
175  else
176  throw std::domain_error(sname() + ": invalid value: o" + str_escape(i));
177  case '-':
178  if ((i = stream.get()) == 'o')
179  if ((i = stream.get()) == 'o')
180  return zero();
181  else
182  throw std::domain_error(sname() + ": invalid value: -o" + str_escape(i));
183  else
184  if (stream >> i)
185  return -i;
186  else
187  sttc::fail_reading(stream, sname() + ": invalid value");
188  default:
189  if (stream >> i)
190  return i;
191  else
192  sttc::fail_reading(stream, sname() + ": invalid value");
193  }
194  }
195 
196  static value_t
197  parse(const std::string & s, size_t& p) {
198  // TODO !!
199  size_t i=p;
200  for(; i>0 && ((s[i-1]>='0' && s[i-1]<='9') || s[i-1]=='e' || s[i-1]=='E' || s[i-1]=='.' || s[i-1]=='+' || s[i-1]=='-'); --i)
201  ;
202  if(i==p)
203  throw parse_exception("Wrong R value");
204  std::istringstream st(s.substr(i, p-i));
205  value_t x;
206  st >> x;
207  p=i;
208  return x;
209  }
210 
211  static std::ostream&
212  print(const value_t v, std::ostream& o,
213  const std::string& format = "text")
214  {
215  if (is_zero(v)) {
216  if(format == "dot")
217  o << "_";
218  else
219  o << "\"-oo\"";
220  }
221  else
222  if (is_one(v)) {
223  if(format == "dot")
224  o << "T";
225  else
226  o << "\"oo\"";
227  }
228  else
229  o << v;
230  return o;
231  }
232 
233  std::ostream&
234  print_set(std::ostream& o, const std::string& format = "text") const
235  {
236  if (format == "latex")
237  o << "\\mathbb{R}_{\\max,\\min}";
238  else if (format == "text")
239  o << "Fuzzy";
240  else
241  raise("invalid format: ", format);
242  return o;
243  }
244 
245 
246  template<unsigned version = version::fsm_json>
247  static
249  {
250  switch (version) {
251  case 0:
252  throw parse_exception("[Fuzzy] Unsupported fsm-json version:"
253  + std::to_string(version));
254  case 1:
255  default:
256  json::object_t* obj = new json::object_t();
257  obj->push_back("semiring",new json::string_t("Fuzzy"));
258  return (obj);
259  }
260  }
261 
262 
263  template<unsigned version = version::fsm_json>
265  const
266  {
267  switch (version) {
268  case 0:
269  throw parse_exception("[Fuzzy] Unsupported fsm-json version:"
270  + std::to_string(version));
271  case 1:
272  default:
273  return new json::float_t(v);
274  }
275  }
276 
277  template<unsigned version = version::fsm_json>
279  const
280  {
281  switch (version) {
282  case 0:
283  case 1:
284  default:
285  try {
286  return p->to_double();
287  } catch (json::coercion_exception&) {}
288  try {
289  std::string str = p->to_string();
290  if (str == "oo")
291  return zero();
292  if (str == "-oo")
293  return one();
294  } catch (json::coercion_exception&) {}
296  "Cannot be coerced to a value of Z-min-max",
297  "maxmin::value_from_json",
298  p);
299  }
300  }
301 
302  };
303 
304  inline maxmin join(const maxmin&, const maxmin&) { return {}; }
305 
306  inline maxmin join(const b&, const maxmin&) { return {}; }
307  inline maxmin join(const maxmin&, const b&) { return {}; }
308 
309 }}//end of ns awali::stc
310 
311 #endif // !AWALI_WEIGHTSET_MAXMIN_HH
Exception used when trying to coerce a node to a given type.
Definition: exceptions.hh:83
Definition: node.hh:503
Definition: node.hh:191
virtual double to_double() const
Coerces this node_t to a double
Definition: node.hh:341
virtual std::string to_string() const
Coerces this node_t to an std::string.
Definition: node.hh:329
Definition: node.hh:365
object_t * push_back(std::string key, node_t *node)
Definition: node.hh:526
The Boolean semring.
Definition: b.hh:38
bool value_t
Definition: b.hh:56
The max-min semiring over floating numbers.
Definition: maxmin.hh:42
static std::string sname()
Definition: maxmin.hh:46
static json::node_t * to_json()
Definition: maxmin.hh:248
static constexpr star_status_t star_status()
Definition: maxmin.hh:141
static constexpr bool is_commutative_semiring()
Definition: maxmin.hh:138
static value_t zero()
Definition: maxmin.hh:104
static value_t conv(b, b::value_t v)
Definition: maxmin.hh:161
value_t value_from_json(json::node_t const *p) const
Definition: maxmin.hh:278
static value_t one()
Definition: maxmin.hh:98
double value_t
Definition: maxmin.hh:63
constexpr static bool is_special(value_t)
Definition: maxmin.hh:121
static value_t transpose(const value_t v)
Definition: maxmin.hh:144
std::ostream & print_set(std::ostream &o, const std::string &format="text") const
Definition: maxmin.hh:234
value_t star(const value_t v) const
Definition: maxmin.hh:92
json::node_t * value_to_json(value_t v) const
Definition: maxmin.hh:264
static bool less_than(value_t lhs, value_t rhs)
Whether lhs < rhs.
Definition: maxmin.hh:116
static bool is_zero(const value_t v)
Definition: maxmin.hh:127
static value_t mul(const value_t l, const value_t r)
Definition: maxmin.hh:74
bool locally_finite_t
Definition: maxmin.hh:64
static size_t hash(value_t v)
Definition: maxmin.hh:149
static value_t conv(std::istream &stream)
Definition: maxmin.hh:167
static const locally_finite_t locally_finite
Definition: maxmin.hh:65
static value_t conv(self_type, value_t v)
Definition: maxmin.hh:155
static value_t add(const value_t l, const value_t r)
Definition: maxmin.hh:68
static bool is_one(const value_t v)
Definition: maxmin.hh:133
static bool equals(const value_t l, const value_t r)
Definition: maxmin.hh:110
static value_t ldiv(const value_t l, const value_t r)
Definition: maxmin.hh:86
static std::ostream & print(const value_t v, std::ostream &o, const std::string &format="text")
Definition: maxmin.hh:212
static value_t parse(const std::string &s, size_t &p)
Definition: maxmin.hh:197
static value_t rdiv(const value_t l, const value_t r)
Definition: maxmin.hh:80
static maxmin make(std::istream &is)
Build from the description in is.
Definition: maxmin.hh:57
static constexpr bool show_one()
Definition: maxmin.hh:140
std::string vname(bool=true) const
Definition: maxmin.hh:51
The semiring of floating Numbers.
Definition: r.hh:35
star_status_t
The different behaviours a weightset may have with respect to the star.
Definition: enums.hh:161
@ STARRABLE
The star of every element exists.
Definition: enums.hh:163
std::string to_string(identities i)
void eat(std::istream &is, char c)
Check lookahead character and advance.
Definition: stream.hh:62
ATTRIBUTE_NORETURN void fail_reading(std::istream &is, std::string explanation)
Throw an exception after failing to read from is.
Definition: stream.hh:93
auto join(const ratexpset< Ctx1 > &a, const ratexpset< Ctx2 > &b) -> ratexpset< join_t< Ctx1, Ctx2 >>
The union of two ratexpsets.
Definition: ratexpset.hh:448
std::ostream & str_escape(std::ostream &os, const int c)
Definition: escape.hh:30
auto format(const ValueSet &vs, const typename ValueSet::value_t &v, Args &&... args) -> std::string
Format v via vs.print.
Definition: stream.hh:109
std::size_t hash_value(const T &v)
Definition: hash.hh:76
ATTRIBUTE_CONST int max(int a, int b)
Definition: arith.hh:54
ATTRIBUTE_CONST int min(int a, int b)
Definition: arith.hh:48
Main namespace of Awali.
Definition: ato.hh:22
Exceptions thrown during parsing.
Definition: parse_exception.hh:26