Question

以下问题可能很容易回答，但我在互联网上找不到任何解决方案。简而言之，我在课堂上放了一些petc函数调用。

以下等式求解器脚本可以正常工作：

static char help[] = "3x3-Equation system\n\n";


#include <petscksp.h>

#undef __FUNCT__
#define __FUNCT__ "main"
int main(int argc,char **argv)
{
  PetscErrorCode ierr;
  PetscMPIInt    rank;
  PetscInt       i,j,N;
  PetscInt   l[] = {0,1,2}; // indices for right hand vector (rhv)
  PetscScalar    vec[] = {0.0,5.0,3.0}; //values of rhv
  PetscScalar    matrix[3][3]= {{-1.0,1.0,1.0},{1.0,-3.0,-2.0},{5.0,1.0,4.0}};
  Vec            b,x;
  Mat            A; 
  KSP            ksp;         /* linear solver context */
  PC             pc;           /* preconditioner context */

  PetscInitialize(&argc,&argv,(char*)0,help);
  ierr = MPI_Comm_rank(PETSC_COMM_WORLD,&rank);CHKERRQ(ierr);
  PetscPrintf(PETSC_COMM_SELF,"[%d] rank\n",rank);

//Init vector
  ierr = VecCreate(PETSC_COMM_WORLD,&b);CHKERRQ(ierr);
  ierr = VecSetSizes(b,3,PETSC_DECIDE);CHKERRQ(ierr);
  ierr = VecSetFromOptions(b);CHKERRQ(ierr);
  ierr = VecDuplicate(b,&x);CHKERRQ(ierr);
  //ierr = VecGetSize(x,&N);CHKERRQ(ierr);
  //ierr = VecSet(x,vec[2]);CHKERRQ(ierr);
  ierr = VecSetValues(b,3,l,vec,INSERT_VALUES);CHKERRQ(ierr);

  ierr = VecAssemblyBegin(b);CHKERRQ(ierr);
  ierr = VecAssemblyEnd(b);CHKERRQ(ierr);

//Init matrix
  ierr = MatCreate(PETSC_COMM_WORLD,&A);CHKERRQ(ierr);
  ierr = MatSetSizes(A,PETSC_DECIDE,PETSC_DECIDE,3,3);CHKERRQ(ierr);
  ierr = MatSetFromOptions(A);CHKERRQ(ierr);
  ierr = MatSetUp(A);CHKERRQ(ierr);
  for(i = 0; i < 3; i++){
    for(j = 0; j < 3; j++){
      ierr = MatSetValues(A,1,&i,1,&j,&matrix[i][j],INSERT_VALUES);CHKERRQ(ierr);
    }
  }
  ierr = MatAssemblyBegin(A,MAT_FINAL_ASSEMBLY);CHKERRQ(ierr);
  ierr = MatAssemblyEnd(A,MAT_FINAL_ASSEMBLY);CHKERRQ(ierr);  

 //Solve
    ierr = KSPCreate(PETSC_COMM_WORLD,&ksp);CHKERRQ(ierr);
    ierr = KSPSetOperators(ksp,A,A,DIFFERENT_NONZERO_PATTERN);CHKERRQ(ierr);
    ierr = KSPGetPC(ksp,&pc);CHKERRQ(ierr);
    ierr = PCSetType(pc,PCJACOBI);CHKERRQ(ierr);
    ierr = KSPSetTolerances(ksp,1.e-5,PETSC_DEFAULT,PETSC_DEFAULT,PETSC_DEFAULT);CHKERRQ(ierr);
    ierr = KSPSetFromOptions(ksp);CHKERRQ(ierr);
    ierr = KSPSolve(ksp,b,x);CHKERRQ(ierr);
    ierr = KSPView(ksp,PETSC_VIEWER_STDOUT_WORLD);CHKERRQ(ierr);

//View rhv 
  PetscPrintf(PETSC_COMM_SELF,"right hand vector:\n");
  ierr = VecView(b,PETSC_VIEWER_STDOUT_WORLD);CHKERRQ(ierr);


//View matrix
  PetscPrintf(PETSC_COMM_SELF,"matrix:\n");
  ierr = MatView(A,PETSC_VIEWER_STDOUT_WORLD);CHKERRQ(ierr);

//View solution 
  PetscPrintf(PETSC_COMM_SELF,"solution:\n");
  ierr = VecView(x,PETSC_VIEWER_STDOUT_WORLD);CHKERRQ(ierr);

 //Clean all
  /*ierr = VecDestroy(&b);CHKERRQ(ierr);
  ierr = VecDestroy(&x);CHKERRQ(ierr);
  ierr = MatDestroy(&A);CHKERRQ(ierr);
  */
  ierr = PetscFinalize();
  return 0;
}

但是当我在一个类中外包代码时，会导致一些错误：

#include <petscksp.h>
static char help[] = "Easy equation solver\n\n";

class externSolver
{
  public:                              
  PetscErrorCode ierr;  
  PetscMPIInt    rank;
  Vec            b,x;
  Mat            A; 
  KSP            ksp;         /* linear solver context */
  PC             pc;           /* preconditioner context */
    externSolver(int argc,char **argv)
    {
        ierr = PetscInitialize(&argc,&argv,(char*)0,help);CHKERRQ(ierr);
    ierr = MPI_Comm_rank(PETSC_COMM_WORLD,&rank);CHKERRQ(ierr);
    ierr = PetscPrintf(PETSC_COMM_SELF,"[%d] rank\n",rank);CHKERRQ(ierr);
    return;
    }
    ~externSolver()
    {

    }
    void generateMatrix(int cols, int rows)
    {
        ierr = MatCreate(PETSC_COMM_WORLD,&A);CHKERRQ(ierr);
    ierr = MatSetSizes(A,PETSC_DECIDE,PETSC_DECIDE,cols,rows);CHKERRQ(ierr);
    ierr = MatSetFromOptions(A);CHKERRQ(ierr);
    ierr = MatSetUp(A);CHKERRQ(ierr);
    }
    void MatSetValues(PetscInt num_rows,PetscInt* rows,PetscInt num_cols,PetscInt* cols,PetscScalar* Value)
    {
      ierr = MatSetValues(A,num_rows,rows,num_cols,cols,Value,INSERT_VALUES);CHKERRQ(ierr);
    }
    void assemblyMatrix()
    {
      ierr = MatAssemblyBegin(A,MAT_FINAL_ASSEMBLY);CHKERRQ(ierr);
      ierr = MatAssemblyEnd(A,MAT_FINAL_ASSEMBLY);CHKERRQ(ierr);  
    }
    void generateVectors()
    {
      ierr = VecCreate(PETSC_COMM_WORLD,&b);CHKERRQ(ierr);
      ierr = VecSetSizes(b,3,PETSC_DECIDE);CHKERRQ(ierr);
      ierr = VecSetFromOptions(b);CHKERRQ(ierr);
      ierr = VecDuplicate(b,&x);CHKERRQ(ierr);
    }
    void VecSetValues(PetscInt num_rows,PetscInt* rows,PetscScalar* Value)
    {
       ierr = VecSetValues(b,num_rows,rows,Value,INSERT_VALUES);CHKERRQ(ierr);
    }
    void assemblyVectors()
    {
        ierr = VecAssemblyBegin(b);CHKERRQ(ierr);
        ierr = VecAssemblyEnd(b);CHKERRQ(ierr);
    }
    void solve()
    {
      ierr = KSPCreate(PETSC_COMM_WORLD,&ksp);CHKERRQ(ierr);
      ierr = KSPSetOperators(ksp,A,A,DIFFERENT_NONZERO_PATTERN);CHKERRQ(ierr);
      ierr = KSPGetPC(ksp,&pc);CHKERRQ(ierr);
      ierr = PCSetType(pc,PCJACOBI);CHKERRQ(ierr);
      ierr = KSPSetTolerances(ksp,1.e-5,PETSC_DEFAULT,PETSC_DEFAULT,PETSC_DEFAULT);CHKERRQ(ierr);
      ierr = KSPSetFromOptions(ksp);CHKERRQ(ierr);
      ierr = KSPSolve(ksp,b,x);CHKERRQ(ierr);
      ierr = KSPView(ksp,PETSC_VIEWER_STDOUT_WORLD);CHKERRQ(ierr);
    }
    void showAll()
    {
      //View right hand vec
      PetscPrintf(PETSC_COMM_SELF,"right hand vec:\n");
      ierr = VecView(b,PETSC_VIEWER_STDOUT_WORLD);CHKERRQ(ierr);


      //View matrix
      PetscPrintf(PETSC_COMM_SELF,"matrix:\n");
      ierr = MatView(A,PETSC_VIEWER_STDOUT_WORLD);CHKERRQ(ierr);

      //View solution
      PetscPrintf(PETSC_COMM_SELF,"solution:\n");
      ierr = VecView(x,PETSC_VIEWER_STDOUT_WORLD);CHKERRQ(ierr);
    }
  void close()
  {
        //Clean up
      ierr = VecDestroy(&b);CHKERRQ(ierr);
      ierr = VecDestroy(&x);CHKERRQ(ierr);
      ierr = MatDestroy(&A);CHKERRQ(ierr);
      ierr = PetscFinalize();
  }
};

这是调用类的脚本：

#include "externSolver.h"

int main(int argc,char **argv)
{
  PetscInt   l[] = {0,1,2}; 
  PetscScalar    vec[] = {0.0,5.0,3.0};
  PetscScalar    matrix[3][3]= {{-1.0,1.0,1.0},{1.0,-3.0,-2.0},{5.0,1.0,4.0}};


  externSolver eS(argc,argv);


//Vector
  eS.generateVectors();
  eS.VecSetValues(3,l,vec);
  eS.assemblyVectors();


//Matrix
  eS.generateMatrix(3,3);
  for(int i = 0; i < 3; i++){
    for(int j = 0; j < 3; j++){
      eS.MatSetValues(1,&i,1,&j,&matrix[i][j]);
    }
  }
  eS.assemblyMatrix();

 //Solve Problem
  eS.solve();

  eS.showAll();
  eS.close();



  return 0;
}

这些是建筑错误：

ex2_extern.cc：5中包含的文件：

externSolver.h: In constructor ‘externSolver::externSolver(int, char**)’:
externSolver.h:15: error: returning a value from a constructor
externSolver.h:16: error: returning a value from a constructor
externSolver.h:17: error: returning a value from a constructor
externSolver.h: In member function ‘void externSolver::generateMatrix(int, int)’:
externSolver.h:26: error: return-statement with a value, in function returning 'void'
externSolver.h:27: error: return-statement with a value, in function returning 'void'
externSolver.h:28: error: return-statement with a value, in function returning 'void'
externSolver.h:29: error: return-statement with a value, in function returning 'void'
externSolver.h: In member function ‘void externSolver::MatSetValues(PetscInt, PetscInt*, PetscInt, PetscInt*, PetscScalar*)’:
externSolver.h:33: error: no matching function for call to ‘externSolver::MatSetValues(_p_Mat*&, PetscInt&, PetscInt*&, PetscInt&, PetscInt*&, PetscScalar*&, InsertMode)’
externSolver.h:31: note: candidates are: void externSolver::MatSetValues(PetscInt, PetscInt*, PetscInt, PetscInt*, PetscScalar*)
externSolver.h:33: error: return-statement with a value, in function returning 'void'
externSolver.h: In member function ‘void externSolver::assemblyMatrix()’:
externSolver.h:37: error: return-statement with a value, in function returning 'void'
externSolver.h:38: error: return-statement with a value, in function returning 'void'
externSolver.h: In member function ‘void externSolver::generateVectors()’:
externSolver.h:42: error: return-statement with a value, in function returning 'void'
externSolver.h:43: error: return-statement with a value, in function returning 'void'
externSolver.h:44: error: return-statement with a value, in function returning 'void'
externSolver.h:45: error: return-statement with a value, in function returning 'void'
externSolver.h: In member function ‘void externSolver::VecSetValues(PetscInt, PetscInt*, PetscScalar*)’:
externSolver.h:49: error: no matching function for call to ‘externSolver::VecSetValues(_p_Vec*&, PetscInt&, PetscInt*&, PetscScalar*&, InsertMode)’
externSolver.h:47: note: candidates are: void externSolver::VecSetValues(PetscInt, PetscInt*, PetscScalar*)
externSolver.h:49: error: return-statement with a value, in function returning 'void'
externSolver.h: In member function ‘void externSolver::assemblyVectors()’:
externSolver.h:53: error: return-statement with a value, in function returning 'void'
externSolver.h:54: error: return-statement with a value, in function returning 'void'
externSolver.h: In member function ‘void externSolver::solve()’:
externSolver.h:58: error: return-statement with a value, in function returning 'void'
externSolver.h:59: error: return-statement with a value, in function returning 'void'
externSolver.h:60: error: return-statement with a value, in function returning 'void'
externSolver.h:61: error: return-statement with a value, in function returning 'void'
externSolver.h:62: error: return-statement with a value, in function returning 'void'
externSolver.h:63: error: return-statement with a value, in function returning 'void'
externSolver.h:64: error: return-statement with a value, in function returning 'void'
externSolver.h:65: error: return-statement with a value, in function returning 'void'
externSolver.h: In member function ‘void externSolver::showAll()’:
externSolver.h:71: error: return-statement with a value, in function returning 'void'
externSolver.h:76: error: return-statement with a value, in function returning 'void'
externSolver.h:80: error: return-statement with a value, in function returning 'void'
externSolver.h: In member function ‘void externSolver::close()’:
externSolver.h:85: error: cannot convert ‘_p_Vec**’ to ‘_p_Vec*’ for argument ‘1’ to ‘PetscErrorCode VecDestroy(_p_Vec*)’
externSolver.h:85: error: return-statement with a value, in function returning 'void'
externSolver.h:86: error: cannot convert ‘_p_Vec**’ to ‘_p_Vec*’ for argument ‘1’ to ‘PetscErrorCode VecDestroy(_p_Vec*)’
externSolver.h:86: error: return-statement with a value, in function returning 'void'
externSolver.h:87: error: cannot convert ‘_p_Mat**’ to ‘_p_Mat*’ for argument ‘1’ to ‘PetscErrorCode MatDestroy(_p_Mat*)’
externSolver.h:87: error: return-statement with a value, in function returning 'void'
ex2_extern.cc: In function ‘int main(int, char**)’:
ex2_extern.cc:14: error: ‘ierr’ was not declared in this scope
ex2_extern.cc:11: warning: unused variable ‘l’
ex2_extern.cc:12: warning: unused variable ‘vec’
ex2_extern.cc:13: warning: unused variable ‘matrix’
make: [ex2_extern.o] Error 1 (ignored)

问题出在哪里？

亲切的问候，塞巴斯蒂安

Answer 1

根据CHKERRQ doc，你需要在函数内使用CHKERRV返回void或任何其他非整数数据类型。

Answer 2

我只能假设您的CHKERRQ宏扩展为类似

的内容

   if (ierr != 0) return ierr;

您可以通过查看编译器消息的行来确定，然后找出该宏的作用。

我认为我不敢评论这段代码的风格。它只需要严肃的重写。使用C代码并使用类中的方法调用将其包装起来并不会使它成为C ++代码。

轻松的petc函数在类中调用

2 个答案: