书上的vector例程,编译不过.费解,请教..谢谢!

[taurusbbstech]

//vect.h -- Vector class with << ,mode state
#ifdef VECTOR_H_
#define VECTOR_H_
#include <iostream>
namespace VECTOR
{
	class Vector
	{
	private:
		double x;
		double y;
		double mag;
		double ang;
		char mode;

		void set_mag();
		void set_ang();
		void set_x();
		void set_y();
	public:
		Vector();
		Vector(double n1, double n2, char form = 'r');
		void set(double n1, double n2, char form = 'r');
		~Vector();
		double xval()const {return x;}
		double yval()const {return y;}
		double magval()const {return mag;}
		double angval()const {return ang;}
		void polar_mode();
		void rect_mode();

		Vector operator+(const Vector & b)const;
		Vector operator-(const Vector & b)const;
		Vector operator-()const;
		Vector operator*(double n)const;

		friend Vector operator*(double n, const Vector & a);
		friend std::ostream & operator<<(std::ostream & os, const Vector & v);
	};
}
#endif
//vect.cpp -- methods for Vector class
#include <cmath>
#include <iostream>
#include "vector.h"
//using std::sin;
//using std::cos;
//using std::atan2;
using std::cout;

namespace VECTOR
{
	const double Rad_to_deg = 57.2957795130823;
	void Vector::set_mag()
	{
		mag - sqrt(x * x + y * y);
	}

	void Vector::set_ang()
	{
		if (x == 0.0 && y == 0.0)
			ang = 0.0;
		else 
			ang = atan2(y, x)
	}

	void Vector::set_x()
	{
		x = mag * cos(ang);
	}
	
	void Vector::set_y()
	{
		y = mag * sin(ang);
	}

	Vector::Vector()
	{
		x = y = mag = ang = 0.0;
		mode = 'r';
	}

	Vector::Vector(double n1, double n2, char form)
	{
		mode = form;
		if (form == 'r')
		{
			x = n1;
			y = n2;
			set_mag();
			set_ang();
		}
		else if (form == 'p')
		{
			mag = n1;
			ang = n2 / Rad_to_deg;
			set_x();
			set_y();
		}
		else
		{
			cout << "Incorrect 3rd argument to Vector() -- ";
			cout << "vector set to 0\n";
			x = y = mag = ang = 0.0;
			mode = 'r';
		}
	}

	void Vector::set(double n1, double n2, char form)
	{
		mode = form;
		if (form == 'r')
		{
			x = n1;
			y = n2;
			set_mag();
			set_ang();
		}
		else if (form == 'p')
		{
			mag = n1;
			ang = n2;
			set_x();
			set_y();
		}
		else
		{
			cout << "Incorrect 3rd argument to Vector()-- ";
			cout << "vector set to 0\n";
			x = y = mag = ang = 0.0;
			mode = 'r';
		}
	}

	Vector::~Vector()
	{
	}

	void Vector::polar_mode()
	{
		mode = 'p';
	}

	void Vector::rect_mode()
	{
		mode = 'r';
	}

	Vector Vector::operator+(const Vector & b)const
	{
		return Vector(x + b.x, y + b.y);
	}

	Vector Vector::operator-(const Vector & b)const
	{
		return Vector(x - b.x, y - b.y);
	}

	Vector Vector::operator-()const
	{
		return Vector(-x, -y);
	}

	Vector Vector::operator*(double n)const
	{
		return Vector(n * x, n * y);
	}

	Vector operator*(double n, const Vector & a)
	{
		return a * n;
	}

	std::ostream & operator<<(std::ostream & os, const Vector & V)
	{
		if (V.mode == 'r')
			os << " (x, y) = (" << V.x << ", " << V.y << ") ";
		else if (V.mode == 'p')
		{
			os << " (m, a) = (" << V.mag << ", " << V.ang * Rad_to_deg << ") ";
		}
		else
			os << "Vector object mode is invalid";
		return os;
	}
}
//randwalk.cpp -- using the Vector class

#include <iostream>
#include <cstdlib>
#include <ctime>
#include "vector.h"

int main()
{
	using namespace std;
	using VECTOR::Vector;
	srand(time(0));
	double direction;
	Vector step;
	Vector result(0.0, 0.0);
	unsigned long steps = 0;
	double target;
	double dstep;
	cout << "Enter target distance(q to quit): ";
	while (cin >> target)
	{
		cout << "Enter step length: ";
		if (!(cin >> dstep))
		break;
		while (result.magval() < target)
		{
			direction = rand() % 360;
			step.set(dstep, direction, 'p');
			result = result + step;
			steps++;
		}
		cout << "After " << steps << " steps, the subject "
			"has the following location:\n";
		cout << result << endl;
		result.polar_mode();
		cout << "or\n" << result << endl;
		cout << "Average outward distance per step = "
			<< result.magval() / steps << endl;
		steps = 0;
		result.set(0.0, 0.0);
		cout << "Enter target distance(q to quit);";
	}
	cout << "Bye!\n";
	return 0;
}

[taodm]

啥编译器，啥错误？
兄弟，要节约别人的时间，才能有好的回报。

[yinyuexiuluo]

当然通不过了,你的vector头文件就错了,
#ifndef VECTOR_H
#define VECTOR_H

[taurusbbstech]

[Quote=引用 1 楼 taodm 的回复:]
啥编译器，啥错误？
兄弟，要节约别人的时间，才能有好的回报。
[/Quote]

VS6

Deleting intermediate files and output files for project 'vector - Win32 Debug'.
--------------------Configuration: vector - Win32 Debug--------------------
Compiling...
randwalk.cpp
\vector\randwalk.cpp(11) : error C2653: 'VECTOR' : is not a class or namespace name
\vector\randwalk.cpp(11) : error C2873: 'Vector' : symbol cannot be used in a using-declaration
\vector\randwalk.cpp(14) : error C2065: 'Vector' : undeclared identifier
\vector\randwalk.cpp(14) : error C2146: syntax error : missing ';' before identifier 'step'
\vector\randwalk.cpp(14) : error C2065: 'step' : undeclared identifier
\vector\randwalk.cpp(15) : error C2146: syntax error : missing ';' before identifier 'result'
\vector\randwalk.cpp(15) : error C2065: 'result' : undeclared identifier
\vector\randwalk.cpp(25) : error C2228: left of '.magval' must have class/struct/union type
\vector\randwalk.cpp(25) : fatal error C1903: unable to recover from previous error(s); stopping compilation
vector.cpp
\vector\vector.cpp(13) : error C2653: 'Vector' : is not a class or namespace name
\vector\vector.cpp(15) : error C2065: 'mag' : undeclared identifier
\vector\vector.cpp(15) : error C2065: 'x' : undeclared identifier
\vector\vector.cpp(15) : error C2065: 'y' : undeclared identifier
\vector\vector.cpp(15) : warning C4552: '-' : operator has no effect; expected operator with side-effect
\vector\vector.cpp(18) : error C2653: 'Vector' : is not a class or namespace name
\vector\vector.cpp(21) : error C2065: 'ang' : undeclared identifier
\vector\vector.cpp(24) : error C2143: syntax error : missing ';' before '}'
\vector\vector.cpp(26) : error C2653: 'Vector' : is not a class or namespace name
\vector\vector.cpp(31) : error C2653: 'Vector' : is not a class or namespace name
\vector\vector.cpp(36) : error C2653: 'Vector' : is not a class or namespace name
\vector\vector.cpp(39) : error C2065: 'mode' : undeclared identifier
\vector\vector.cpp(40) : warning C4508: 'Vector' : function should return a value; 'void' return type assumed
\vector\vector.cpp(42) : error C2653: 'Vector' : is not a class or namespace name
\vector\vector.cpp(66) : warning C4508: 'Vector' : function should return a value; 'void' return type assumed
\vector\vector.cpp(69) : fatal error C1903: unable to recover from previous error(s); stopping compilation
Error executing cl.exe.
Creating browse info file...
BSCMAKE: error BK1506 : cannot open file '.\Debug\randwalk.sbr': No such file or directory
Error executing bscmake.exe.

vector.exe - 23 error(s), 3 warning(s)

[hellodudu]

hehe up ls
lz粗心了

[taodm]

不要叫vector.h。重名了。

[taurusbbstech]

[Quote=引用 2 楼 yinyuexiuluo 的回复:]
当然通不过了,你的vector头文件就错了,
#ifndef VECTOR_H
#define VECTOR_H
[/Quote]
为什么这样是错的?

[liyuzhu_1984]

那本书上的？ 你的程序引用头文件可能有错误

[taurusbbstech]

[Quote=引用 5 楼 taodm 的回复:]
不要叫vector.h。重名了。
[/Quote]
改成vect.h,还是一样的错.

[taurusbbstech]

[Quote=引用 7 楼 liyuzhu_1984 的回复:]
那本书上的？ 你的程序引用头文件可能有错误
[/Quote]
C++ primer plus.

[iambic]

因为你没定义VECTOR_H，所以后面的东西都被预处理去掉了。
#ifdef VECTOR_H
//everything...
#endif

[taodm]

哈哈，如果你书上真是#ifdef VECTOR_H
你还是把这书扔了吧。

[taurusbbstech]

呵呵..粗心了,谢谢大家.

[星羽]

你先去google一下 #ifdef #ifndef 的作用吧

[taurusbbstech]

[Quote=引用 13 楼 Chiyer 的回复:]
你先去google一下 #ifdef #ifndef 的作用吧
[/Quote]
我知道,是打错了.

[taurusbbstech]

还有被我注释了的三条

//using std::sin;
//using std::cos;
//using std::atan2;

书上确是这样用的.

[AwL_1124]

求解决方法

[AwL_1124]

修改vector.cpp、randwalk.cpp中#include内容为： "vect.h"