侯捷《C++面向对象开发》--复数类的实现
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//防范式声明,可理解为:if not define __COMPLEX__,接下来 define __COMPLEX__ #ifndef __COMPLEX__ #define __COMPLEX__ #include<ostream> class complex { public: complex(const double r=0, const double i=0) //构造函数,r和i的默认参数为0 :re(r),im(i) //初始化:将re初始化为r,im初始化为i {} //操作符重载,参数中实际上还包含一个隐藏参数this,返回的是一个complex的引用 complex& operator += (const complex&); complex& operator -= (const complex&); complex& operator *= (const complex&); complex& operator /= (const complex&); // 成员函数,用于查看一个complex对象的实数部分和虚数部分,我们不希望这部分被更改,所以添加const double real() const { return re; } double imag() const { return im; } //成员函数,用于计算共轭复数 complex conjugate() const { return complex(this->real(), -1 * this->imag()); } private: double re, im; // 友元函数,友元函数不是类的成员函数,但友元函数可以通过.操作获取类的private变量。友元函数打破了类的封装 friend complex& __doapl(complex*, const complex&); friend complex& __doami(complex*, const complex&); friend complex& __doamu(complex*, const complex&); }; //重载+= complex& __doapl(complex* ths, const complex& x) { ths->re += x.re; ths->im += x.im; return *ths; } complex& complex::operator += (const complex& x) { return __doapl(this, x); } //重载-= complex& __doami(complex* ths, const complex& x) { ths->re -= x.re; ths->im -= x.im; return *ths; } complex& complex::operator-= (const complex& x) { return __doami(this, x); } //重载*= complex& __doamu(complex* ths, const complex& x) { double temp = ths->re * x.re - ths->im * x.im; ths->im = (ths->re * x.im + ths->im * x.re); ths->re = temp; return *ths; } complex& complex::operator*= (const complex& x) { return __doamu(this, x); } //重载/= complex& __doadiv(complex* ths, const complex& x) { double r = (ths->real() * x.real() + ths->imag() * x.imag()) / (x.real() * x.real() + x.imag() * x.imag()); double i = (ths->imag() * x.real() - ths->real() * x.imag()) / (x.real() * x.real() + x.imag() * x.imag()); *ths = complex(r, i); return *ths; } complex& complex::operator/= (const complex& x) { return __doadiv(this, x); } //重载+操作,具体分为三种情况:复数+复数、复数+实数、复数+实数。其它重载操作类似 // 这里返回的不是reference,而是一个value。 //不能返回reference的原因是:进行‘+’操作后得到的对象,存放在一个临时的complex中。 //这个临时对象的生命周期在函数结束时结束。 complex operator + (const complex& c1, const complex& c2) { return complex(c1.real() + c2.real(), c1.imag() + c2.imag()); } complex operator + (const complex& c1, const double& c2) { return complex(c1.real() + c2, c1.imag()); } complex operator + (const double& c1, const complex& c2) { return complex(c1 + c2.real(), c2.imag()); } complex operator - (const complex& c1, const complex& c2) { return complex(c1.real() - c2.real(), c1.imag() - c2.imag()); } complex operator - (const complex& c1, const double& c2) { return complex(c1.real() - c2, c1.imag()); } complex operator - (const double& c1, const complex& c2) { return complex(c1 - c2.real(), c2.imag()); } complex operator * (const complex& c1, const complex& c2) { double r = c1.real() * c2.real() - c1.imag() * c2.imag(); double i = c1.real() * c2.imag() + c1.imag() * c2.real(); return complex(r, i); } complex operator / (const complex& c1, const complex& c2) { double r = (c1.real() * c2.real() + c1.imag() * c2.imag()) / (c2.real() * c2.real() + c2.imag() * c2.imag()); double i = (c1.imag() * c2.real() - c1.real() * c2.imag()) / (c2.real() * c2.real() + c2.imag() * c2.imag()); return complex(r, i); } inline double real(const complex& x) { return x.real(); } inline double imag(const complex& x) { return x.imag(); } // 重载输出操作 std::ostream& operator << (std::ostream& os, const complex& x) { return os << "(" << real(x) << "," << imag(x) << ")"; } #endif // !__COMPLEX__ #include"complex.h" #include<ostream> #include<iostream> using namespace std; int main() { complex c1(double(1), double(2)); while (1) { double a, b,c,d; cin >> a >> b >> c >> d; complex c1(a, b); complex c2(c, d); cout << "c1" << c1 << endl; cout << "c2" <<c2 << endl; cout << "conjugate" << c1.conjugate() << endl; cout << "c1/c2=" << (c1 / c2) << endl; cout << "c1*c2=" << (c1 * c2) << endl; cout << "c1-c2=" << (c1 - c2) << endl; cout << "c1+c2=" << (c1 + c2) << endl; cout << "c1*=c2=" << (c1 *= c2) << endl; cout << real(c1) << " " <<imag(c1) << endl; } return 0; }
标签:real,const,--,imag,C++,complex,侯捷,c2,c1 来源: https://www.cnblogs.com/alan-W/p/14171077.html