Files
SimplexTASK/tools/elimination.cpp
T

119 lines
2.9 KiB
C++

#include "elimination.h"
#include "math.h"
FracturedMatrix::FracturedMatrix(const FracturedMatrix &other) : A(other.A), C(other.C), b(other.b), pivot_column_index(other.pivot_column_index), pivot_row_index(other.pivot_row_index) {}
FracturedMatrix::FracturedMatrix(Matrix A, Vector C, Vector b, int pivot_column_index, int pivot_row_index) : A(A), C(C), b(b), pivot_column_index(pivot_column_index), pivot_row_index(pivot_row_index) {}
FracturedMatrix &FracturedMatrix::operator=(const FracturedMatrix &other)
{
A = other.A;
C = other.C;
b = other.b;
pivot_column_index = other.pivot_column_index;
pivot_row_index = other.pivot_row_index;
return *this;
}
DestroyMatrix disassembleGeneralMatrix(Matrix &generalMatrix)
{
int rows = generalMatrix.getRows();
int cols = generalMatrix.getColumns();
Matrix A(rows - 1, cols - 1);
Vector C(cols - 1);
Vector b(rows);
for (int j = 0; j < cols - 1; ++j)
{
C[j] = generalMatrix[0][j];
}
for (int i = 0; i < rows; ++i)
{
b[i] = generalMatrix[i][cols - 1];
}
for (int i = 1; i < rows; ++i)
{
for (int j = 0; j < cols - 1; ++j)
{
A[i - 1][j] = generalMatrix[i][j];
}
}
return {A, C, b};
}
Matrix createGeneralMatrix(Matrix &A, Vector &C, Vector &b)
{
int m = A.getRows() + 1;
int n = A.getColumns() + A.getRows() + 1;
Matrix generalMatrix(m, n);
for (int i = 0; i < n; i++)
{
if (i < C.size())
{
generalMatrix[0][i] = C[i];
}
else
{
generalMatrix[0][i] = 0;
}
}
// For objective function (j=0) the value is set to zero one step before
for (int j = 1; j < m; j++)
{
generalMatrix[j][n - 1] = b[j - 1];
}
int k = 0;
for (int i = 0; i < m - 1; i++)
{
for (int j = 0; j < n - 1; j++)
{
if (j < A.getColumns())
{
generalMatrix[i + 1][j] = A[i][j];
}
else
{
generalMatrix[i + 1][j] = 0;
}
}
generalMatrix[i + 1][A.getColumns() + k] = 1;
++k;
}
return generalMatrix;
}
void elimination(Matrix &generalMatrix, int pivot_row_index, int pivot_column_index)
{
int rows = generalMatrix.getRows();
int cols = generalMatrix.getColumns();
double pivotElement = generalMatrix[pivot_row_index][pivot_column_index];
for (int j = 0; j < cols; ++j)
{
generalMatrix[pivot_row_index][j] /= pivotElement;
}
for (int i = 0; i < rows; ++i)
{
if (i == pivot_row_index)
continue;
double pivotColumnCoefficient = generalMatrix[i][pivot_column_index];
for (int j = 0; j < cols; ++j)
{
generalMatrix[i][j] -= pivotColumnCoefficient * generalMatrix[pivot_row_index][j];
}
}
}