mv util/lp to math/lp

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

src/math/lp/column_namer.h

@@ -0,0 +1,61 @@
+#pragma once
+/*++
+Copyright (c) 2017 Microsoft Corporation
+
+Module Name:
+
+    <name>
+
+Abstract:
+
+    <abstract>
+
+Author:
+
+    Lev Nachmanson (levnach)
+
+Revision History:
+
+
+--*/
+#include <string>
+#include "math/lp/static_matrix.h"
+namespace lp {
+class column_namer {
+public:
+    virtual std::string get_variable_name(unsigned j) const = 0;
+    template <typename T>
+    void print_row(const row_strip<T> & row, std::ostream & out) const {
+        vector<std::pair<T, unsigned>> coeff;
+        for (auto & p : row) {
+            coeff.push_back(std::make_pair(p.coeff(), p.var()));
+        }
+        print_linear_combination_of_column_indices(coeff, out);
+    }
+    
+    template <typename T>
+    void print_linear_combination_of_column_indices(const vector<std::pair<T, unsigned>> & coeffs, std::ostream & out) const {
+        bool first = true;
+        for (const auto & it : coeffs) {
+            auto val = it.first;
+            if (first) {
+                first = false;
+            } else {
+                if (numeric_traits<T>::is_pos(val)) {
+                    out << " + ";
+                } else {
+                    out << " - ";
+                    val = -val;
+                }
+            }
+            if (val == -numeric_traits<T>::one())
+                out << " - ";
+            else if (val != numeric_traits<T>::one())
+                out << val;
+        
+            out << get_variable_name(it.second);
+        }
+    }
+
+};
+}