基于C++的n阶线性方程组Ax=b求解

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基于C++的n阶线性方程组Ax=b求解：

bool CUtil::Solve(double** A, double* b, double* x, int n){  double** M = new double*[n];  for (int i=0; i<n; i++)  {  M[i] = new double[n+1];  for (int j=0; j<n; j++)  {  M[i][j] = A[i][j];  }  M[i][n] = b[i];  }  for (int k=0; k<n; k++)  {//n个主元  double colMax = fabs(M[k][k]);  int maxLineIndex = k;  for(int i=k+1; i<n; i++)  {//寻找第k列的最大元素  if(fabs(M[i][k]) > colMax)  {  colMax = fabs(M[i][k]);  maxLineIndex = i;  }  }  if(colMax < EPSILONG)  {//奇异矩阵  for (int i=0; i<n; i++)  {  delete M[i];  }  delete M;  return false;  }  double temp;  //交换k行和maxLineIndex行  for (int m=0; m<n+1; m++)  {  temp = M[k][m];  M[k][m] = M[maxLineIndex][m];  M[maxLineIndex][m] = temp;  }  //消去  for(int i=k+1; i<n; i++)  {  for (int j=k+1; j<n+1; j++)  {  M[i][j] = M[k][k]*M[i][j]/M[i][k] - M[k][j];  }  }  }  //回归求解  for (int i=n-1; i>=0; i--)  {  x[i] = M[i][n];  for (int j=i+1; j<n; j++)  {  x[i] -= M[i][j]*x[j];  }  x[i] /= M[i][i];  }  for (int i=0; i<n; i++)  {  delete M[i];  }  delete M;  return true;  }

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