[ADD] CMakeLists.txt

[MODIFIED] add variable, must to increase column index.

Author: ytsao

CMakeLists.txt

@@ -0,0 +1,11 @@
+cmake_minimum_required(VERSION 3.24)
+cmake_policy(SET CMP0135 NEW)
+
+project(simplex
+  HOMEPAGE_URL "https://github.com/ytsao/simplex-method.git"
+  LANGUAGES CXX
+)
+
+add_executable(simplex main.cpp)
+target_include_directories(simplex PRIVATE include)
+target_compile_features(simplex PRIVATE cxx_std_17)

include/SOPModel.hpp

@@ -26,7 +26,7 @@ class SOPModel {
     SOPVariables create_nonbasic(std::string name, char type, int id, double lb, double ub){
       SOPVariables new_var = SOPVariables(name, type, id, lb, ub);
       this->nonbasic.push_back(new_var);
-      this->num_cols;
+      this->num_cols++;
 
       return new_var;
     }

include/SOPlpsolver.hpp

@@ -61,6 +61,7 @@ class SOPlpSolve : public SOPSolver {
     }
 
     bool primal_simplex(SOPModel& model) {
+        this->p_iterations = 0;
         // step1. optimality test
         while (!optimality(model.get_header())) {
             /*std::cout << "finish step 1" << std::endl;*/
@@ -119,7 +120,6 @@ class SOPlpSolve : public SOPSolver {
             // step 7. compute dual step length
             // s = z_star_j / delta_z_j
             double s = model.get_header()(entering_index) / delta_z_N[entering_index];
-            /*std::cout << "finish step 7" << std::endl;*/
 
             // step 8. update current primal and dual solution
             for (int i = 0; i < model.get_num_rows(); ++i) {
@@ -155,13 +155,16 @@ class SOPlpSolve : public SOPSolver {
             /*std::cout << "entering variable index:" << entering_index << ", name: " << entering_variable.get_var_name() << std::endl;*/
             /*std::cout << "leaving variable index:" << leaving_index << ", name: " << leaving_variable.get_var_name() << std::endl;*/
             /*std::cout << "finish step 9" << std::endl;*/
-            /**/
+
             this->p_iterations++;
         }
+        std::cout << "number of iterations: " << this->p_iterations << std::endl;
+
         return true;
     }
 
     bool dual_simplex(SOPModel& model) {
+        this->d_iterations = 0;
         // step 1. optimality test
         while (!optimality(model.get_rhs())) {
             /*std::cout << "finish step 1" << std::endl;*/
@@ -255,6 +258,8 @@ class SOPlpSolve : public SOPSolver {
 
             this->d_iterations++;
         }
+        std::cout << "number of iterations: " << this->d_iterations << std::endl;
+
         return true;
     }
 

main

@@ -11,49 +11,46 @@ int main() {
     // create decision variables
     SOPVariables x1 = model.create_nonbasic("x1", 'F', 0, 0, INT_MAX);
     SOPVariables x2 = model.create_nonbasic("x2", 'F', 1, 0, INT_MAX);
-    SOPVariables x3 = model.create_nonbasic("x3", 'F', 2, 0, INT_MAX);
 
-    /*std::cout << x1.get_var_name() << std::endl;*/
-    /*std::cout << x2.get_var_name() << std::endl;*/
+    std::cout << x1.get_var_name() << std::endl;
+    std::cout << x2.get_var_name() << std::endl;
 
     // create objective function
     SOPObjective obj;
-    obj.addTerm(3, x1);
-    obj.addTerm(6, x2);
-    obj.addTerm(0, x3);
-    model.addMin(obj);
+    obj.addTerm(-2, x1);
+    obj.addTerm(-1, x2);
+    model.addMax(obj);
 
-    /*std::cout << model.get_header() << std::endl;*/
+    std::cout << "header: " << model.get_header() << std::endl;
 
     // create bunch of constraints
-    expr.addTerm(-1, x1);
-    expr.addTerm(2, x2);
-    expr.addTerm(-1, x3);
-    model.addLe(expr, -6, "cons1");
-
-    expr.addTerm(-2, x1);
+    expr.addTerm(-3, x1);
     expr.addTerm(-1, x2);
-    expr.addTerm(2, x3);
-    model.addLe(expr, -8, "cons2");
+    model.addLe(expr, -3, "cons1");
 
-    expr.addTerm(0, x1);
-    expr.addTerm(1, x2);
-    model.addLe(expr, 5, "cons3");
+    expr.addTerm(-4, x1);
+    expr.addTerm(-3, x2);
+    model.addLe(expr, -6, "cons2");
+
+    expr.addTerm(-1, x1);
+    expr.addTerm(-2, x2);
+    model.addLe(expr, -3, "cons3");
 
     model.create_basis();
     std::cout << "basis: " << model.get_basis() << std::endl;
     std::cout << "all ranges: " << model.get_all_range() << std::endl;
     std::cout << "N: " << model.get_N() << std::endl;
     std::cout << "rhs: " << model.get_rhs() << std::endl;
 
-    for (int i = 0; i < 2; i++) std::cout << "variable index: " << model.get_basic(i).get_var_id() << std::endl;
+    for (int i = 0; i < 2; i++) std::cout << "basic variable index: " << model.get_basic(i).get_var_id() << std::endl;
 
 #pragma endregion
 
 #pragma region solve linear program
     SOPlpSolve lpsolver;
-    lpsolver.solve(model, 1);
+    lpsolver.solve(model, 2);
     std::cout << "after solving, rhs: " << model.get_rhs() << std::endl;
+    for (int i = 0; i < 2; i++) std::cout << "basic variable index: " << model.get_basic(i).get_var_id() << std::endl;
 #pragma endregion
 
     std::cout << "finish" << std::endl;