Question

代码中某处出现错误，但我不知道如何解决。它说“模板参数列表太少”。我不明白哪个是错误。

以下是代码：

#if !defined(VECTOR_H_INCLUDED)
#         define         VECTOR_H_INCLUDED


namespace Vec
{
    class Vector_base
    {
            public:
                    explicit Vector_base() {}
                    virtual ~Vector_base() {}

    };

    template<typename T, int DIM>
    class Vector : public Vector_base
    {
            typedef Vector<T,DIM> ME;
            public:
                    explicit Vector()
                    {
                            memset(&v, 0, sizeof(v));
                    }

                    explicit Vector(T v[DIM])
                    {
                            memcpy(this->v, v, sizeof(this->v));
                    }

                    explicit Vector(T,T,T);

                    virtual ~Vector()
                    {

                    }

                    // Operators

                    T &operator [](size_t n)
                    {
                            return v[n];
                    }

                    T operator [](size_t n) const
                    {
                            return v[n];
                    }

                    ME &operator += (const ME& o)
                    {
                            for (size_t i=0; i<DIM; ++i)
                            {
                                    v[i] += o[i];
                            }
                            return *this;
                    }

                    ME &operator -= (const ME& o)
                    {
                            for (size_t i=0; i<DIM; ++i)
                            {
                                    v[i] -= o[i];
                            }
                            return *this;
                    }

                    ME &operator *= (const ME& o)
                    {
                            for (size_t i=0; i<DIM; ++i)
                            {
                                    v[i] *= o[i];
                            }
                            return *this;
                    }

                    ME &operator /= (const ME& o)
                    {
                            for (size_t i=0; i<DIM; ++i)
                            {
                                    v[i] /= o[i];
                            }
                            return *this;
                    }


                    ME &operator *= (double scalar)
                    {
                            for (size_t i=0; i<DIM; ++i)
                            {
                                    v[i] *= scalar;
                            }
                            return *this;
                    }

                    ME &operator /= (double scalar)
                    {
                            for (size_t i=0; i<DIM; ++i)
                            {
                                    v[i] /= scalar;
                            }
                            return *this;
                    }


                    const ME operator-(const ME &o) const
                    {
                            ME result = *this;
                            result -= o;
                            return result;
                    }

                    const ME operator+(const ME &o) const
                    {
                            ME result = *this;
                            result += o;
                            return result;
                    }

                    const ME operator*(const ME &o) const
                    {
                            ME result = *this;
                            result *= o;
                            return result;
                    }

                    const ME operator*(double scalar) const
                    {
                            ME result = *this;
                            result *= scalar;
                            return result;
                    }

                    const ME operator/(const ME &o) const
                    {
                            ME result = *this;
                            result /= o;
                            return result;
                    }

                    const ME operator/(double scalar) const
                    {
                            ME result = *this;
                            result /= scalar;
                            return result;
                    }



                    // Misc stuff
                    ME &get()
                    {
                            return v;
                    }

                    double length()
                    {
                            double temp = 0.0f;

                            for (size_t i=0; i<DIM; ++i)
                            {
                                    temp += v[i] * v[i];
                            }

                            return sqrtf(temp);
                    }

                    void normalize()
                    {
                            double len = length();

                            for (size_t i=0; i<DIM; ++i)
                            {
                                    v[i] /= len;
                            }

                    }

                    double dot(const ME &v) const;


            private:
                    T v[DIM];
    };


    typedef Vector<double,3> Vector3;



    double Vector3::dot(const ME &o) const // ----- it gives me the error here ...
    {
            return v[0] * o[0] + v[1] * o[1] + v[2] * o[2];
    }

    Vector3::Vector(double x, double y, double z) // ----- ... and here
    {
            v[0] = x;
            v[1] = y;
            v[2] = z;
    }

}

#endif // VECTOR_H_INCLUDED

我需要改变什么？

提前致谢。对不起我的英语，我在学校学习英语作为第二语言。

Answer 1

您应该在此处使用template<>进行模板特化。

template<> double Vector3::dot(const ME &o) const

和

template<> Vector3::Vector(double x, double y, double z)

“模板参数列表太少”错误

1 个答案: