merge LRA

Signed-off-by: Nikolaj Bjorner <nbjorner@microsoft.com>

src/util/lp/indexed_value.h

@@ -0,0 +1,55 @@
+/*
+  Copyright (c) 2017 Microsoft Corporation
+  Author: Lev Nachmanson
+*/
+#pragma once
+
+namespace lean {
+template <typename T>
+class indexed_value {
+public:
+    T m_value;
+    // the idea is that m_index for a row element gives its column, and for a column element its row
+    unsigned m_index;
+    // m_other point is the offset of the corresponding element in its vector : for a row element it point to the column element offset,
+    // for a column element it points to the row element offset
+    unsigned m_other;
+    indexed_value() {}
+    indexed_value(T v, unsigned i) : m_value(v), m_index(i) {}
+    indexed_value(T v, unsigned i, unsigned other) :
+        m_value(v), m_index(i), m_other(other) {
+    }
+
+    indexed_value(const indexed_value & iv) {
+        m_value = iv.m_value;
+        m_index = iv.m_index;
+        m_other = iv.m_other;
+    }
+
+    indexed_value & operator=(const indexed_value & right_side) {
+        m_value = right_side.m_value;
+        m_index = right_side.m_index;
+        m_other = right_side.m_other;
+        return *this;
+    }
+
+    const T & value() const {
+        return m_value;
+    }
+
+    void set_value(T val) {
+        m_value = val;
+    }
+};
+#ifdef LEAN_DEBUG
+template <typename X>
+bool check_vector_for_small_values(indexed_vector<X> & w, lp_settings & settings) {
+    for (unsigned i : w.m_index) {
+        const X & v = w[i];
+        if ((!is_zero(v)) && settings.abs_val_is_smaller_than_drop_tolerance(v))
+            return false;
+    }
+    return true;
+}
+#endif
+}