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alpar (Alpar Juttner)
alpar@cs.elte.hu
Accept negative values as unbounded capacity in dimacs readers (#243) and some doc improvements.
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3 files changed with 87 insertions and 26 deletions:
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Ignore white space 6 line context
... ...
@@ -21,11 +21,11 @@
21 21

	
22 22
#include <iostream>
23 23
#include <string>
24 24
#include <vector>
25
#include <limits>
25 26
#include <lemon/maps.h>
26 27
#include <lemon/error.h>
27

	
28 28
/// \ingroup dimacs_group
29 29
/// \file
30 30
/// \brief DIMACS file format reader.
31 31

	
... ...
@@ -54,9 +54,9 @@
54 54
  };
55 55

	
56 56
  ///Discover the type of a DIMACS file
57 57

	
58
  ///It starts seeking the begining of the file for the problem type
58
  ///It starts seeking the beginning of the file for the problem type
59 59
  ///and size info. The found data is returned in a special struct
60 60
  ///that can be evaluated and passed to the appropriate reader
61 61
  ///function.
62 62
  DimacsDescriptor dimacsType(std::istream& is)
... ...
@@ -104,11 +104,19 @@
104 104
  /// \code
105 105
  ///   p min
106 106
  /// \endcode
107 107
  /// At the beginning, \c g is cleared by \c g.clear(). The supply
108
  /// amount of the nodes are written to \c supply (signed). The
109
  /// lower bounds, capacities and costs of the arcs are written to
110
  /// \c lower, \c capacity and \c cost.
108
  /// amount of the nodes are written to the \c supply node map
109
  /// (they are signed values). The lower bounds, capacities and costs
110
  /// of the arcs are written to the \c lower, \c capacity and \c cost
111
  /// arc maps.
112
  ///
113
  /// If the capacity of an arc is less than the lower bound, it will
114
  /// be set to "infinite" instead. The actual value of "infinite" is
115
  /// contolled by the \c infty parameter. If it is 0 (the default value),
116
  /// \c std::numeric_limits<Capacity>::infinity() will be used if available,
117
  /// \c std::numeric_limits<Capacity>::max() otherwise. If \c infty is set to
118
  /// a non-zero value, that value will be used as "infinite".
111 119
  ///
112 120
  /// If the file type was previously evaluated by dimacsType(), then
113 121
  /// the descriptor struct should be given by the \c dest parameter.
114 122
  template <typename Digraph, typename LowerMap,
... ...
@@ -119,8 +127,9 @@
119 127
                     LowerMap& lower,
120 128
                     CapacityMap& capacity,
121 129
                     CostMap& cost,
122 130
                     SupplyMap& supply,
131
                     typename CapacityMap::Value infty = 0,
123 132
                     DimacsDescriptor desc=DimacsDescriptor())
124 133
  {
125 134
    g.clear();
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    std::vector<typename Digraph::Node> nodes;
... ...
@@ -141,8 +150,14 @@
141 150
    typename SupplyMap::Value sup;
142 151
    typename CapacityMap::Value low;
143 152
    typename CapacityMap::Value cap;
144 153
    typename CostMap::Value co;
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    typedef typename CapacityMap::Value Capacity;
155
    if(infty==0)
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      infty = std::numeric_limits<Capacity>::has_infinity ?
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        std::numeric_limits<Capacity>::infinity() :
158
        std::numeric_limits<Capacity>::max();
159

	
145 160
    while (is >> c) {
146 161
      switch (c) {
147 162
      case 'c': // comment line
148 163
        getline(is, str);
... ...
@@ -151,17 +166,17 @@
151 166
        is >> i >> sup;
152 167
        getline(is, str);
153 168
        supply.set(nodes[i], sup);
154 169
        break;
155
      case 'a': // arc (arc) definition line
170
      case 'a': // arc definition line
156 171
        is >> i >> j >> low >> cap >> co;
157 172
        getline(is, str);
158 173
        e = g.addArc(nodes[i], nodes[j]);
159 174
        lower.set(e, low);
160
        if (cap >= 0)
175
        if (cap >= low)
161 176
          capacity.set(e, cap);
162 177
        else
163
          capacity.set(e, -1);
178
          capacity.set(e, infty);
164 179
        cost.set(e, co);
165 180
        break;
166 181
      }
167 182
    }
... ...
@@ -172,8 +187,9 @@
172 187
                   Digraph &g,
173 188
                   CapacityMap& capacity,
174 189
                   typename Digraph::Node &s,
175 190
                   typename Digraph::Node &t,
191
                   typename CapacityMap::Value infty = 0,
176 192
                   DimacsDescriptor desc=DimacsDescriptor()) {
177 193
    g.clear();
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    s=t=INVALID;
179 195
    std::vector<typename Digraph::Node> nodes;
... ...
@@ -185,9 +201,15 @@
185 201
    nodes.resize(desc.nodeNum + 1);
186 202
    for (int k = 1; k <= desc.nodeNum; ++k) {
187 203
      nodes[k] = g.addNode();
188 204
    }
205
    typedef typename CapacityMap::Value Capacity;
189 206

	
207
    if(infty==0)
208
      infty = std::numeric_limits<Capacity>::has_infinity ?
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        std::numeric_limits<Capacity>::infinity() :
210
        std::numeric_limits<Capacity>::max();
211
 
190 212
    while (is >> c) {
191 213
      switch (c) {
192 214
      case 'c': // comment line
193 215
        getline(is, str);
... ...
@@ -204,16 +226,25 @@
204 226
          if (d == 's') s = nodes[i];
205 227
          if (d == 't') t = nodes[i];
206 228
        }
207 229
        break;
208
      case 'a': // arc (arc) definition line
209
        if (desc.type==DimacsDescriptor::SP ||
210
            desc.type==DimacsDescriptor::MAX) {
230
      case 'a': // arc definition line
231
        if (desc.type==DimacsDescriptor::SP) {
211 232
          is >> i >> j >> _cap;
212 233
          getline(is, str);
213 234
          e = g.addArc(nodes[i], nodes[j]);
214 235
          capacity.set(e, _cap);
215
        } else {
236
        } 
237
        else if (desc.type==DimacsDescriptor::MAX) {
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          is >> i >> j >> _cap;
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          getline(is, str);
240
          e = g.addArc(nodes[i], nodes[j]);
241
          if (_cap >= 0)
242
            capacity.set(e, _cap);
243
          else
244
            capacity.set(e, infty);
245
        }
246
        else {
216 247
          is >> i >> j;
217 248
          getline(is, str);
218 249
          g.addArc(nodes[i], nodes[j]);
219 250
        }
... ...
@@ -229,10 +260,17 @@
229 260
  /// \code
230 261
  ///   p max
231 262
  /// \endcode
232 263
  /// At the beginning, \c g is cleared by \c g.clear(). The arc
233
  /// capacities are written to \c capacity and \c s and \c t are
234
  /// set to the source and the target nodes.
264
  /// capacities are written to the \c capacity arc map and \c s and
265
  /// \c t are set to the source and the target nodes.
266
  ///
267
  /// If the capacity of an arc is negative, it will
268
  /// be set to "infinite" instead. The actual value of "infinite" is
269
  /// contolled by the \c infty parameter. If it is 0 (the default value),
270
  /// \c std::numeric_limits<Capacity>::infinity() will be used if available,
271
  /// \c std::numeric_limits<Capacity>::max() otherwise. If \c infty is set to
272
  /// a non-zero value, that value will be used as "infinite".
235 273
  ///
236 274
  /// If the file type was previously evaluated by dimacsType(), then
237 275
  /// the descriptor struct should be given by the \c dest parameter.
238 276
  template<typename Digraph, typename CapacityMap>
... ...
@@ -240,13 +278,14 @@
240 278
                     Digraph &g,
241 279
                     CapacityMap& capacity,
242 280
                     typename Digraph::Node &s,
243 281
                     typename Digraph::Node &t,
282
                     typename CapacityMap::Value infty = 0,
244 283
                     DimacsDescriptor desc=DimacsDescriptor()) {
245 284
    if(desc.type==DimacsDescriptor::NONE) desc=dimacsType(is);
246 285
    if(desc.type!=DimacsDescriptor::MAX)
247 286
      throw FormatError("Problem type mismatch");
248
    _readDimacs(is,g,capacity,s,t,desc);
287
    _readDimacs(is,g,capacity,s,t,infty,desc);
249 288
  }
250 289

	
251 290
  /// DIMACS shortest path reader function.
252 291
  ///
... ...
@@ -255,9 +294,9 @@
255 294
  /// \code
256 295
  ///   p sp
257 296
  /// \endcode
258 297
  /// At the beginning, \c g is cleared by \c g.clear(). The arc
259
  /// lengths are written to \c length and \c s is set to the
298
  /// lengths are written to the \c length arc map and \c s is set to the
260 299
  /// source node.
261 300
  ///
262 301
  /// If the file type was previously evaluated by dimacsType(), then
263 302
  /// the descriptor struct should be given by the \c dest parameter.
... ...
@@ -270,30 +309,40 @@
270 309
    typename Digraph::Node t;
271 310
    if(desc.type==DimacsDescriptor::NONE) desc=dimacsType(is);
272 311
    if(desc.type!=DimacsDescriptor::SP)
273 312
      throw FormatError("Problem type mismatch");
274
    _readDimacs(is, g, length, s, t,desc);
313
    _readDimacs(is, g, length, s, t, 0, desc);
275 314
  }
276 315

	
277 316
  /// DIMACS capacitated digraph reader function.
278 317
  ///
279 318
  /// This function reads an arc capacitated digraph instance from
280
  /// DIMACS 'mat' or 'sp' format.
319
  /// DIMACS 'max' or 'sp' format.
281 320
  /// At the beginning, \c g is cleared by \c g.clear()
282
  /// and the arc capacities/lengths are written to \c capacity.
321
  /// and the arc capacities/lengths are written to the \c capacity
322
  /// arc map.
323
  ///
324
  /// In case of the 'max' format, if the capacity of an arc is negative,
325
  /// it will
326
  /// be set to "infinite" instead. The actual value of "infinite" is
327
  /// contolled by the \c infty parameter. If it is 0 (the default value),
328
  /// \c std::numeric_limits<Capacity>::infinity() will be used if available,
329
  /// \c std::numeric_limits<Capacity>::max() otherwise. If \c infty is set to
330
  /// a non-zero value, that value will be used as "infinite".
283 331
  ///
284 332
  /// If the file type was previously evaluated by dimacsType(), then
285 333
  /// the descriptor struct should be given by the \c dest parameter.
286 334
  template<typename Digraph, typename CapacityMap>
287 335
  void readDimacsCap(std::istream& is,
288 336
                     Digraph &g,
289 337
                     CapacityMap& capacity,
338
                     typename CapacityMap::Value infty = 0,
290 339
                     DimacsDescriptor desc=DimacsDescriptor()) {
291 340
    typename Digraph::Node u,v;
292 341
    if(desc.type==DimacsDescriptor::NONE) desc=dimacsType(is);
293 342
    if(desc.type!=DimacsDescriptor::MAX || desc.type!=DimacsDescriptor::SP)
294 343
      throw FormatError("Problem type mismatch");
295
    _readDimacs(is, g, capacity, u, v, desc);
344
    _readDimacs(is, g, capacity, u, v, infty, desc);
296 345
  }
297 346

	
298 347
  template<typename Graph>
299 348
  typename enable_if<lemon::UndirectedTagIndicator<Graph>,void>::type
... ...
@@ -346,9 +395,9 @@
346 395
        getline(is, str);
347 396
        break;
348 397
      case 'n': // node definition line
349 398
        break;
350
      case 'a': // arc (arc) definition line
399
      case 'a': // arc definition line
351 400
        is >> i >> j;
352 401
        getline(is, str);
353 402
        _addArcEdge(g,nodes[i], nodes[j]);
354 403
        break;
Ignore white space 8 line context
... ...
@@ -71,17 +71,17 @@
71 71
}
72 72

	
73 73
template<class Value>
74 74
void solve_max(ArgParser &ap, std::istream &is, std::ostream &,
75
              DimacsDescriptor &desc)
75
               Value infty, DimacsDescriptor &desc)
76 76
{
77 77
  bool report = !ap.given("q");
78 78
  Digraph g;
79 79
  Node s,t;
80 80
  Digraph::ArcMap<Value> cap(g);
81 81
  Timer ti;
82 82
  ti.restart();
83
  readDimacsMax(is, g, cap, s, t, desc);
83
  readDimacsMax(is, g, cap, s, t, infty, desc);
84 84
  if(report) std::cerr << "Read the file: " << ti << '\n';
85 85
  ti.restart();
86 86
  Preflow<Digraph, Digraph::ArcMap<Value> > pre(g,cap,s,t);
87 87
  if(report) std::cerr << "Setup Preflow class: " << ti << '\n';
... ...
@@ -114,16 +114,27 @@
114 114
template<class Value>
115 115
void solve(ArgParser &ap, std::istream &is, std::ostream &os,
116 116
           DimacsDescriptor &desc)
117 117
{
118
  std::stringstream iss(ap["infcap"]);
119
  Value infty;
120
  iss >> infty;
121
  if(iss.fail())
122
    {
123
      std::cerr << "Cannot interpret '"
124
                << static_cast<std::string>(ap["infcap"]) << "' as infinite"
125
                << std::endl;
126
      exit(1);
127
    }
128
  
118 129
  switch(desc.type)
119 130
    {
120 131
    case DimacsDescriptor::MIN:
121 132
      std::cerr <<
122 133
        "\n\n Sorry, the min. cost flow solver is not yet available.\n";
123 134
      break;
124 135
    case DimacsDescriptor::MAX:
125
      solve_max<Value>(ap,is,os,desc);
136
      solve_max<Value>(ap,is,os,infty,desc);
126 137
      break;
127 138
    case DimacsDescriptor::SP:
128 139
      solve_sp<Value>(ap,is,os,desc);
129 140
      break;
... ...
@@ -158,8 +169,9 @@
158 169
    .optionGroup("datatype","double")
159 170
    .boolOption("ldouble","Use 'long double' for capacities, costs etc.")
160 171
    .optionGroup("datatype","ldouble")
161 172
    .onlyOneGroup("datatype")
173
    .stringOption("infcap","Value used for 'very high' capacities","0")
162 174
    .run();
163 175

	
164 176
  std::ifstream input;
165 177
  std::ofstream output;
Ignore white space 6 line context
... ...
@@ -95,9 +95,9 @@
95 95
      {
96 96
        Digraph digraph;
97 97
        DoubleArcMap lower(digraph), capacity(digraph), cost(digraph);
98 98
        DoubleNodeMap supply(digraph);
99
        readDimacsMin(is, digraph, lower, capacity, cost, supply, desc);
99
        readDimacsMin(is, digraph, lower, capacity, cost, supply, 0, desc);
100 100
        DigraphWriter<Digraph>(digraph, os).
101 101
          nodeMap("supply", supply).
102 102
          arcMap("lower", lower).
103 103
          arcMap("capacity", capacity).
... ...
@@ -110,9 +110,9 @@
110 110
      {
111 111
        Digraph digraph;
112 112
        Node s, t;
113 113
        DoubleArcMap capacity(digraph);
114
        readDimacsMax(is, digraph, capacity, s, t, desc);
114
        readDimacsMax(is, digraph, capacity, s, t, 0, desc);
115 115
        DigraphWriter<Digraph>(digraph, os).
116 116
          arcMap("capacity", capacity).
117 117
          node("source", s).
118 118
          node("target", t).
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