From 5521172ed1b44c2a7ba26d8904c196322a2dcb14 Mon Sep 17 00:00:00 2001
From: dehnert <dehnert@cs.rwth-aachen.de>
Date: Mon, 7 Sep 2015 19:35:37 +0200
Subject: [PATCH] more work on sparse game solver

Former-commit-id: df95038635005f6d12cd612629f1815944839923
---
 src/solver/GameSolver.cpp | 66 ++++++++++++++++++++++++++++++++++++---
 src/solver/GameSolver.h   | 12 ++++++-
 2 files changed, 73 insertions(+), 5 deletions(-)

diff --git a/src/solver/GameSolver.cpp b/src/solver/GameSolver.cpp
index 27ccf27a5..cc9e83916 100644
--- a/src/solver/GameSolver.cpp
+++ b/src/solver/GameSolver.cpp
@@ -1,17 +1,75 @@
 #include "src/solver/GameSolver.h"
 
+#include "src/storage/SparseMatrix.h"
+
+#include "src/utility/vector.h"
+
 namespace storm {
     namespace solver {
-        GameSolver::GameSolver(storm::storage::SparseMatrix<storm::storage::sparse::state_type> const& player1Matrix, storm::storage::SparseMatrix<ValueType> const& player2Matrix) : AbstractGameSolver(), player1Matrix(player1Matrix), player2Matrix(player2Matrix) {
+        template <typename ValueType>
+        GameSolver<ValueType>::GameSolver(storm::storage::SparseMatrix<storm::storage::sparse::state_type> const& player1Matrix, storm::storage::SparseMatrix<ValueType> const& player2Matrix) : AbstractGameSolver(), player1Matrix(player1Matrix), player2Matrix(player2Matrix) {
             // Intentionally left empty.
         }
 
-        GameSolver::GameSolver(storm::storage::SparseMatrix<storm::storage::sparse::state_type> const& player1Matrix, storm::storage::SparseMatrix<ValueType> const& player2Matrix, double precision, uint_fast64_t maximalNumberOfIterations, bool relative) : AbstractGameSolver(precision, maximalNumberOfIterations, relative), player1Matrix(player1Matrix), player2Matrix(player2Matrix) {
+        template <typename ValueType>
+        GameSolver<ValueType>::GameSolver(storm::storage::SparseMatrix<storm::storage::sparse::state_type> const& player1Matrix, storm::storage::SparseMatrix<ValueType> const& player2Matrix, double precision, uint_fast64_t maximalNumberOfIterations, bool relative) : AbstractGameSolver(precision, maximalNumberOfIterations, relative), player1Matrix(player1Matrix), player2Matrix(player2Matrix) {
             // Intentionally left empty.
         }
 
-        void GameSolver::solveGame(OptimizationDirection player1Goal, OptimizationDirection player2Goal, std::vector<ValueType>& x, storm::dd::Add<Type> const& b) const {
-            // TODO
+        template <typename ValueType>
+        void GameSolver<ValueType>::solveGame(OptimizationDirection player1Goal, OptimizationDirection player2Goal, std::vector<ValueType>& x, std::vector<ValueType> const& b) const {
+            // Set up the environment for value iteration.
+            uint_fast64_t numberOfPlayer1States = x.size();
+
+            bool converged = false;
+            std::vector<ValueType> tmpResult(numberOfPlayer1States);
+            std::vector<ValueType> nondetResult(player2Matrix.getRowCount());
+            std::vector<ValueType> player2Result(player2Matrix.getRowGroupCount());
+
+            // Now perform the actual value iteration.
+            uint_fast64_t iterations = 0;
+            do {
+                player2Matrix.multiplyWithVector(x, nondetResult);
+                storm::utility::vector::addVectors(b, nondetResult, nondetResult);
+
+                if (player2Goal == OptimizationDirection::Minimize) {
+                    storm::utility::vector::reduceVectorMin(nondetResult, player2Result, player2Matrix.getRowGroupIndices());
+                } else {
+                    storm::utility::vector::reduceVectorMax(nondetResult, player2Result, player2Matrix.getRowGroupIndices());
+                }
+
+                for (uint_fast64_t pl1State = 0; pl1State < numberOfPlayer1States; ++pl1State) {
+                    uint_fast64_t startRow = player1Matrix.getRowGroupIndices()[pl1State];
+                    uint_fast64_t endRow = player1Matrix.getRowGroupIndices()[pl1State + 1];
+
+                    storm::storage::SparseMatrix<storm::storage::sparse::state_type>::const_rows relevantRows = player1Matrix.getRows(startRow, endRow - 1);
+                    storm::storage::SparseMatrix<storm::storage::sparse::state_type>::const_iterator it = relevantRows.begin();
+                    storm::storage::SparseMatrix<storm::storage::sparse::state_type>::const_iterator ite = relevantRows.end();
+
+                    // Set the first value.
+                    tmpResult[pl1State] = player2Result[it->getColumn()];
+                    ++it;
+
+                    // Now iterate through the different values and pick the extremal one.
+                    if (player1Goal == OptimizationDirection::Minimize) {
+                        for (; it != ite; ++it) {
+                            tmpResult[pl1State] = std::min(tmpResult[pl1State], player2Result[it->getColumn()]);
+                        }
+                    } else {
+                        for (; it != ite; ++it) {
+                            tmpResult[pl1State] = std::max(tmpResult[pl1State], player2Result[it->getColumn()]);
+                        }
+                    }
+                }
+
+                // Check if the process converged and set up the new iteration in case we are not done.
+                converged = storm::utility::vector::equalModuloPrecision(x, tmpResult, precision, relative);
+                std::swap(x, tmpResult);
+
+                ++iterations;
+            } while (!converged);
         }
+
+        template class GameSolver<double>;
     }
 }
\ No newline at end of file
diff --git a/src/solver/GameSolver.h b/src/solver/GameSolver.h
index 35ce8204a..8218768cc 100644
--- a/src/solver/GameSolver.h
+++ b/src/solver/GameSolver.h
@@ -1,9 +1,19 @@
 #ifndef STORM_SOLVER_GAMESOLVER_H_
 #define STORM_SOLVER_GAMESOLVER_H_
 
+#include <vector>
+
 #include "src/solver/AbstractGameSolver.h"
+#include "src/solver/OptimizationDirection.h"
+
+#include "src/storage/sparse/StateType.h"
 
 namespace storm {
+    namespace storage {
+        template<typename ValueType>
+        class SparseMatrix;
+    }
+
     namespace solver {
         template<typename ValueType>
         class GameSolver : public AbstractGameSolver {
@@ -37,7 +47,7 @@ namespace storm {
              * @param b The vector to add after matrix-vector multiplication.
              * @return The solution vector in the for of the vector x.
              */
-            virtual void solveGame(OptimizationDirection player1Goal, OptimizationDirection player2Goal, std::vector<ValueType>& x, storm::dd::Add<Type> const& b) const;
+            virtual void solveGame(OptimizationDirection player1Goal, OptimizationDirection player2Goal, std::vector<ValueType>& x, std::vector<ValueType> const& b) const;
 
         private:
             // The matrix defining the choices of player 1.