mv util/lp to math/lp

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

src/math/lp/permutation_matrix.h

@@ -0,0 +1,148 @@
+/*++
+Copyright (c) 2017 Microsoft Corporation
+
+Module Name:
+
+    <name>
+
+Abstract:
+
+    <abstract>
+
+Author:
+
+    Lev Nachmanson (levnach)
+
+Revision History:
+
+
+--*/
+#pragma once
+#include "util/vector.h"
+#include <algorithm>
+#include "util/debug.h"
+#include <string>
+#include "math/lp/sparse_vector.h"
+#include "math/lp/indexed_vector.h"
+#include "math/lp/lp_settings.h"
+#include "math/lp/matrix.h"
+#include "math/lp/tail_matrix.h"
+namespace lp {
+#ifdef Z3DEBUG
+    inline bool is_even(int k) {  return (k/2)*2 == k; }
+#endif
+
+    template <typename T, typename X>
+class permutation_matrix : public tail_matrix<T, X> {
+        vector<unsigned> m_permutation;
+        vector<unsigned> m_rev;
+        vector<unsigned> m_work_array;
+        vector<T> m_T_buffer;
+        vector<X> m_X_buffer;
+
+
+        class ref {
+            permutation_matrix & m_p;
+            unsigned m_i;
+        public:
+            ref(permutation_matrix & m, unsigned i):m_p(m), m_i(i) {}
+
+            ref & operator=(unsigned  v) { m_p.set_val(m_i, v); return *this; }
+
+            ref & operator=(ref const & v) {
+                m_p.set_val(m_i, v.m_p.m_permutation[v.m_i]);
+                return *this;
+            }
+            operator unsigned & () const { return m_p.m_permutation[m_i]; }
+        };
+
+    public:
+        permutation_matrix() {}
+        permutation_matrix(unsigned length);
+
+        permutation_matrix(unsigned length, vector<unsigned> const & values);
+        // create a unit permutation of the given length
+        void init(unsigned length);
+        unsigned get_rev(unsigned i) { return m_rev[i]; }
+        bool is_dense() const override { return false; }
+#ifdef Z3DEBUG
+        permutation_matrix get_inverse() const {
+            return permutation_matrix(size(), m_rev);
+        }
+        void print(std::ostream & out) const;
+#endif
+
+        ref operator[](unsigned i) { return ref(*this, i); }
+
+        unsigned operator[](unsigned i) const { return m_permutation[i]; }
+
+        void apply_from_left(vector<X> & w, lp_settings &) override;
+
+        void apply_from_left_to_T(indexed_vector<T> & w, lp_settings & settings) override;
+
+        void apply_from_right(vector<T> & w) override;
+
+        void apply_from_right(indexed_vector<T> & w) override;
+        
+        template <typename L>
+        void copy_aside(vector<L> & t, vector<unsigned> & tmp_index, indexed_vector<L> & w);
+
+        template <typename L>
+        void clear_data(indexed_vector<L> & w);
+
+        template <typename L>
+        void apply_reverse_from_left(indexed_vector<L> & w);
+
+        void apply_reverse_from_left_to_T(vector<T> & w);
+        void apply_reverse_from_left_to_X(vector<X> & w);
+
+        void apply_reverse_from_right_to_T(vector<T> & w);
+        void apply_reverse_from_right_to_T(indexed_vector<T> & w);
+        void apply_reverse_from_right_to_X(vector<X> & w);
+
+        void set_val(unsigned i, unsigned pi) {
+            lp_assert(i < size() && pi < size());  m_permutation[i] = pi;  m_rev[pi] = i;  }
+
+        void transpose_from_left(unsigned i, unsigned j);
+
+        unsigned apply_reverse(unsigned i) const { return m_rev[i];  }
+
+        void transpose_from_right(unsigned i, unsigned j);
+#ifdef Z3DEBUG
+        T get_elem(unsigned i, unsigned j) const override {
+            return m_permutation[i] == j? numeric_traits<T>::one() : numeric_traits<T>::zero();
+        }
+        unsigned row_count() const override { return size(); }
+        unsigned column_count() const override { return size(); }
+        void set_number_of_rows(unsigned /*m*/) override { }
+        void set_number_of_columns(unsigned /*n*/) override { }
+#endif
+        void multiply_by_permutation_from_left(permutation_matrix<T, X> & p);
+
+        // this is multiplication in the matrix sense
+        void multiply_by_permutation_from_right(permutation_matrix<T, X> & p);
+
+        void multiply_by_reverse_from_right(permutation_matrix<T, X> & q);
+
+        void multiply_by_permutation_reverse_from_left(permutation_matrix<T, X> & r);
+
+        void shrink_by_one_identity();
+
+        bool is_identity() const;
+
+        unsigned size() const { return static_cast<unsigned>(m_rev.size()); }
+
+        void resize(unsigned size) {
+            unsigned old_size = m_permutation.size();
+            m_permutation.resize(size);
+            m_rev.resize(size);
+            m_T_buffer.resize(size);
+            m_X_buffer.resize(size);
+            for (unsigned i = old_size; i < size; i++) {
+                m_permutation[i] = m_rev[i] = i;
+    }
+        }
+        
+    }; // end of the permutation class
+
+}