Question

我的结果有问题。实际上，我创建了一个Vector类，然后重新定义了运算符。但是，运营商＆＃34; - ＆＃34;给我两个不同的结果进行相同的操作。当我打印操作时，它给了我很好的答案，但是当我想将结果存入变量时，结果是不同的。

我是否想念班上的操作员？

我的主要是：

#include "../include/Vecteur.hpp"


int main(){
  vec3f v0(1.0f, 1.0f, 1.0f);
  vec3f v1(1.0f, 0.0f, 0.0f);

  v1.x() += 3.0f;
  v0[1] -= 1.0f;

  cout << "v0 = " << v0 << endl;
  cout << "v1 = " << v1 << endl;

  float l = v0.length();
  v1 *= l;

  cout << "l = " << l << endl;
  cout << "v0 = " << v0 << endl;
  cout << "v1 = " << v1 << endl;

  auto v2 = v0 + v1;
  cout << "v2 = " << v2 << endl;

  auto v3 = v0 - v1; // The problem is there.
  cout << "v0 = " << v0 << endl;
  cout << "v1 = " << v1 << endl;
  cout << "v3 = " << v3 << endl; // Prints [1,0,1] instead of [-4.65685, 0, 1]
  cout << v0-v1 << endl; // Prints [-4.65685, 0, 1]

  if (v2 < v3){
    v2 += v3;
  }
  cout << "v2 = " << v2 << endl;
  return 0;
}

有我的班级：

#include <iostream>
#include <math.h>

using namespace std;

class vec3f{

private:
  float tableau[3];

public:

  vec3f(){}
  vec3f(float f1, float f2, float f3){
    this->tableau[0] = f1;
    this->tableau[1] = f2;
    this->tableau[2] = f3;
  }

  float x() const{
    return this->tableau[0];
  }

  float y() const{
    return this->tableau[1];
  }

  float z() const{
    return this->tableau[2];
  }

  float & x(){
    return this->tableau[0];
  }

  float & y(){
    return this->tableau[1];
  }

  float & z(){
    return this->tableau[2];
  }

  float length() const{
    return sqrt(( pow(this->tableau[0],2) + pow(this->tableau[1],2) + pow(this->tableau[2],2) ));
  }

  /* Redifinition of operators */

  vec3f operator+(vec3f const & v){
    this->tableau[0] += v.x();
    this->tableau[1] += v.y();
    this->tableau[2] += v.z();

    return *this;
  }

  vec3f operator-(vec3f const & v){
    this->tableau[0] -= v.x();
    this->tableau[1] -= v.y();
    this->tableau[2] -= v.z();

    return *this;
  }

  vec3f operator*=(float const & f){
    this->tableau[0] *= f;
    this->tableau[1] *= f;
    this->tableau[2] *= f;

    return *this;
  }

  bool operator<(vec3f const & v){
    return (this->tableau[0]<v.x() && this->tableau[1]<v.y() && this->tableau[2]<v.z());
  }

  vec3f & operator=(vec3f const & v){
    return *this;
  }

  vec3f operator=(vec3f const & v) const{
    return *this;
  }

  float operator[](size_t i) const{
    return tableau[i];
  }

  float & operator[](size_t i){
    return tableau[i];
  }

};

ostream & operator<<(ostream & out, vec3f const & v){
  out << "[" << v.x() << ", " << v.y() << ", " << v.z() << "]";
  return out;
}

vec3f operator+(vec3f const & va, vec3f const & vb){
  return vec3f(va.x()+vb.x(),va.y()+vb.y(),va.z()+vb.z());
}

vec3f operator-(vec3f const & va, vec3f const & vb){
  return vec3f(va.x()-vb.x(),va.y()-vb.y(),va.z()-vb.z());
}

vec3f operator+=(vec3f const & va, vec3f const & vb){
  return vec3f(va.x()+vb.x(),va.y()+vb.y(),va.z()+vb.z());
}

谢谢：）

Answer 1

在课程中，您可能希望定义运算符+=和-=（就像您为*=所做的那样）。但您忘了= - 并将+，-定义为修改操作数的成员函数。

运算符有两个不同的结果 - 在c ++ 11中

1 个答案: