Export NL model: write var defs #232

include/mp/flat/constr_base.h

@@ -10,6 +10,7 @@
 
 #include "mp/format.h"
 #include "mp/error.h"
+#include "mp/common.h"
 
 #include "mp/flat/context.h"
 #include "mp/arrayref.h"
@@ -346,6 +347,11 @@ class ConditionalConstraint :
   }
 };
 
+/// Write a readable variable definition
+template <class Writer>
+void WriteVar(Writer& pr, const char* name,
+              double lb, double ub, var::Type ty);
+
 /// Write a CondCon
 template <class JW, class Con>
 inline void WriteJSON(JW jw,

include/mp/flat/converter.h

@@ -503,8 +503,8 @@ class FlatConverter :
     MPD( CloseGraphExporter() );
     if (value_presolver_.GetExport())
       assert( value_presolver_.AllEntriesExported() );
-//    if (GetEnv().verbose_mode())
-      GetEnv().PrintWarnings();
+//  Printing always.  if (GetEnv().verbose_mode())
+    GetEnv().PrintWarnings();
   }
 
   /// Check linear constraints.

include/mp/flat/converter_model.h

@@ -88,8 +88,13 @@ class FlatModel
         MiniJSONWriter jw(wrt);
         int i_actual = i+i_start;
         jw["VAR_index"] = i_actual;
-        if (var_names_storage_.size() > i)
+        if (var_names_storage_.size() > i_actual) {
+          int i = i_actual;
           jw["name"] = var_names_[i];
+          fmt::MemoryWriter pr;
+          WriteVar(pr, var_names_[i], lbs[i], ubs[i], types[i]);
+          jw["printed"] = pr.c_str();
+        }
         jw["bounds"]
             << (lbs[i] < -DBL_MAX ? -DBL_MAX : lbs[i])
             << (ubs[i] > DBL_MAX ? DBL_MAX : ubs[i]);

include/mp/problem.h

@@ -478,43 +478,43 @@ class BasicProblem : public ExprFactory, public SuffixManager {
   /// Normal variable name
   const std::string& var_name(int i) {
     assert(0<=i && i<num_vars());
-    if ((int)var_names().size()<=i)
-      var_names_.resize(num_vars());
-    if (var_names_[i].empty())
-      var_names_[i] = "_x[" + std::to_string(i+1) + "]";
-    return var_names_[i];
+    return item_name(i, var_names_, num_vars(), "_x[");
   }
   /// Defined variable name
   const std::string& dvar_name(int i) {
     assert(0<=i && i<num_common_exprs());
     i += num_vars();
-    if ((int)var_names().size()<=i)
-      var_names_.resize(num_vars()+num_common_exprs());
-    if (var_names_[i].empty())
-      var_names_[i] = "_sdvar[" + std::to_string(i+1) + "]";
-    return var_names_[i];
+    return item_name(i, var_names_,
+                     num_vars()+num_common_exprs(), "_x[",
+                     num_vars(), "_sdvar[");
   }
   /// Constraint name
   const std::string& con_name(int i) {
     assert(0<=i && i<num_cons());
-    if ((int)con_names().size()<=i)
-      con_names_.resize(num_cons());
-    if (con_names_[i].empty())
-      con_names_[i]
-          = (i<num_algebraic_cons() ? "_CON" : "_LCON")
-          + std::to_string(i+1);
-    return con_names_[i];
+    return item_name(i, con_names_,
+                     num_cons(),  "_CON",
+                     num_algebraic_cons(), "_LCON");
   }
   /// Objective name
   const std::string& obj_name(int i) {
     assert(0<=i && i<num_objs());
-    if ((int)obj_names().size()<=i)
-      obj_names_.resize(num_objs());
-    if (obj_names_[i].empty())
-      obj_names_[i] = "_OBJ" + std::to_string(i+1);
-    return obj_names_[i];
+    return item_name(i, obj_names_, num_objs(), "_OBJ");
   }
 
+protected:
+  /// Return names[i].
+  /// Generate names[old_size...n-1] if needed,
+  /// so that the whole vector is valid,
+  /// even if only some variables/cons/objs were queried.
+  /// From [n2], name 'stub2'[i-n2] is given.
+  /// If stub/stub2 ends with a '[', ']' is added after the index.
+  static const std::string& item_name(
+      int i, std::vector<std::string>& names,
+      int n, const char* stub,
+      int n2=std::numeric_limits<int>::max(),
+      const char* stub2=nullptr);
+
+public:
   /** Returns the variable names (if present).
    *  After normal variables follow defined variables.
    */

src/problem.cc

@@ -112,7 +112,43 @@ void BasicProblem<Alloc>::SetInfo(const NLProblemInfo &info) {
   nonlinear_exprs_.reserve(num_common_exprs);
 }
 
-/// Instantiate
+template <typename Params>
+const std::string& BasicProblem<Params>::item_name(
+    int i, std::vector<std::string>& names,
+    int n, const char* stub,  int n2, const char* stub2) {
+  assert(0<=i && i<n);
+  if ((int)names.size()<n) {
+    int sz0 = (int)names.size();
+    names.resize(n);
+    int k=sz0;
+    auto gen_names = [&names](
+        int k, int n, const char* stub, int k_sub=0) {
+      for ( ; k<n; k++) {
+        assert(stub);
+        int l = std::strlen(stub);
+        assert(l);
+        bool fbr = '['==stub[l-1];
+        names[k] = stub;
+        names[k] += std::to_string(k-k_sub+1);
+        if (fbr)
+          names[k] += ']';
+      }
+    };
+    if (n2>=0 && n2<n) {
+      if (k<n2) {
+        gen_names(k, n2, stub);
+        gen_names(n2, n, stub2, n2);
+      } else
+        gen_names(k, n, stub2, n2);
+    } else
+      gen_names(k, n, stub);
+  }
+  assert(names[i].size());
+  return names[i];
+}
+
+// Instantiations
+
 template class BasicProblem< >;
 
 template void ReadNLFile(fmt::CStringRef filename, Problem &p, int flags);

src/std_constr.cc

@@ -1,8 +1,10 @@
 #include <map>
+#include <cfloat>
 #include <cassert>
 
 #include "mp/format.h"
 #include "mp/util-json-write.hpp"
+#include "mp/common.h"
 
 #include "mp/flat/expr_quadratic.h"
 #include "mp/flat/model_info.hpp"
@@ -70,6 +72,31 @@ void QuadTerms::sort_terms()  {
   }
 }
 
+template <class Writer>
+void WriteVar(Writer& pr, const char* name,
+              double lb, double ub, var::Type ty) {
+  assert(*name);
+  pr << "var " << name;
+  if (!lb && 1.0==ub && var::INTEGER==ty)
+    pr << " binary";
+  else if (lb==ub)
+    pr << " = " << lb;
+  else {
+    if (lb >= -DBL_MAX)
+    pr << " >=" << lb;
+    if (ub <= DBL_MAX)
+    pr << " <=" << ub;
+    if (var::INTEGER == ty)
+    pr << " integer";
+  }
+  pr << ';';
+}
+
+// Generate
+template
+void WriteVar(fmt::MemoryWriter& pr, const char* name,
+              double lb, double ub, var::Type ty);
+
 template <>
 void WriteJSON(JSONW jw, const QuadTerms& qt) {
   jw["coefs"] = qt.coefs();

test/end2end/cases/categorized/fast/suf_common/modellist.json

@@ -31,6 +31,14 @@
       "solve_result_num": 0
     }
   },
+  {
+    "name": "mipbound_01 objno=0 writegraph",
+    "tags": [ "linear", "return_mipgap"],
+    "options": { "ANYSOLVER_options": "objno=0 writegraph=mipb_01.jsonl" },
+    "values": {
+      "solve_result_num": 0
+    }
+  },
   {
     "name" : "dietu_stt sensitivity=1",
     "objective" : 74.273820,