add compare() to nla_expr

Signed-off-by: Lev Nachmanson <levnach@hotmail.com>

src/math/lp/cross_nested.h

@@ -25,6 +25,7 @@ class cross_nested {
     typedef nla_expr<rational> nex;
     nex& m_e;
     std::function<void (const nex&)> m_call_on_result;
+    std::set<nex> m_reported;
 public:
     cross_nested(nex &e, std::function<void (const nex&)> call_on_result): m_e(e), m_call_on_result(call_on_result) {}
 
@@ -48,7 +49,15 @@ public:
             if(front.empty()) {
                 TRACE("nla_cn_cn", tout << "got the cn form: m_e=" << m_e << "\n";);
                 SASSERT(!can_be_cross_nested_more(m_e));
-                m_call_on_result(m_e);
+                auto e_to_report = m_e;
+                e_to_report.simplify();
+                e_to_report.sort();
+                if (m_reported.find(e_to_report) == m_reported.end()) {
+                    m_reported.insert(e_to_report);
+                    m_call_on_result(e_to_report);
+                } else {
+                    TRACE("nla_cn", tout << "do not report " << e_to_report << "\n";);
+                }
             } else {
                 nex* c = pop_back(front);
                 cross_nested_of_expr_on_front_elem(c, front);     
@@ -67,7 +76,6 @@ public:
                     *(front[i]) = copy_of_front[i];
             }
         }
-        TRACE("nla_cn", tout << "exit\n";);
     }
     // e is the global expression, c is the sub expressiond which is going to changed from sum to the cross nested form
     void cross_nested_of_expr_on_sum_and_var(nex* c, lpvar j, vector<nex*> front) {

src/math/lp/horner.cpp

@@ -42,9 +42,12 @@ void horner::lemmas_on_expr(nex& e) {
     TRACE("nla_cn", tout << "e = " << e << "\n";);    
     TRACE("nla_cn_cn", tout << "e = " << e << "\n";);
     cross_nested cn(e, [this](const nex& n) {
+                           TRACE("nla_cn", tout << "callback n = " << n << "\n";);
                            auto i = interval_of_expr(n);
                            m_intervals.check_interval_for_conflict_on_zero(i);} );
     cn.run();
+    TRACE("nla_cn", tout << "lemmas_on_expr done\n";);    
+    
 }
 
 

src/math/lp/nla_expr.h

@@ -20,7 +20,7 @@
 #include <initializer_list>
 #include "math/lp/nla_defs.h"
 namespace nla {
-enum class expr_type { SUM, MUL, VAR, SCALAR, UNDEF };
+enum class expr_type { VAR, SUM, MUL, SCALAR, UNDEF };
 inline std::ostream & operator<<(std::ostream& out, expr_type t) {
     switch (t) {
     case expr_type::SUM:
@@ -73,6 +73,21 @@ class nla_expr {
         void sort() {
             std::sort(m_order.begin(), m_order.end(), [this](unsigned i, unsigned j) { return m_es[i] < m_es[j]; });
         }
+        bool operator<(const sorted_children& e) const {
+            return compare(e) == -1;
+        }
+
+        int compare(const sorted_children& e) const {
+            unsigned m = std::min(size(), e.size());
+            for (unsigned j = 0; j < m; j++) {
+                int r = m_es[m_order[j]].compare(e.m_es[e.m_order[j]]);
+                if (r == -1)
+                    return true;
+                if (r == 1)
+                    return false;
+            }
+            return size() < e.size();
+        }
     };
 
     // todo: use union
@@ -295,6 +310,27 @@ public:
         }
         return false;
     }
+
+    int compare(const nla_expr& e) const {
+        if (type() != (e.type()))
+            return (int)type() - (int)(e.type());
+        SASSERT(type() == (e.type()));
+
+        switch(m_type) {
+        case expr_type::SUM:
+        case expr_type::MUL:
+            return m_children.compare(e.m_children);
+             
+        case expr_type::VAR:
+            return m_j - e.m_j;
+        case expr_type::SCALAR:
+            return m_v < e.m_v? -1 : (m_v == e.m_v? 0 : 1);
+        default:
+            SASSERT(false);
+            return 0;
+        }
+    }
+    
     bool operator<(const nla_expr& e) const {
         if (type() != (e.type()))
             return (int)type() < (int)(e.type());
@@ -304,7 +340,8 @@ public:
         switch(m_type) {
         case expr_type::SUM:
         case expr_type::MUL:
-            return m_children.es() < e.m_children.es();
+            return m_children < e.m_children;
+             
         case expr_type::VAR:
             return m_j < e.m_j;
         case expr_type::SCALAR:

src/test/lp/lp.cpp

@@ -84,11 +84,12 @@ void test_cn() {
     typedef horner::nex nex;
     enable_trace("nla_cn");
     enable_trace("nla_cn_details");
+    enable_trace("nla_cn_cn");
     nex a = nex::var(0), b = nex::var(1), c = nex::var(2), d = nex::var(3), e = nex::var(4);
     
-    nex t = a*a*d + a*b*c*d + a*a*c*c*d + a*d*d + e*a*e + e*a*c + e*d;
+    test_cn_on_expr(a*b*d + a*b*c + c*b*d);
-    test_cn_on_expr(t);
+    // nex t = a*a*d + a*b*c*d + a*a*c*c*d + a*d*d + e*a*e + e*a*c + e*d;
-    test_cn_on_expr(a*b*d + a*b*c);
+    // test_cn_on_expr(t);
 }
 
 } // end of namespace nla