I create a fraction class,when I call the DtoF(convert double into fraction) function,the compiler said DtoF function is not found(Code:C3861). But the other friend functions,like some overloaded functions (+,-,*,/) works fine.Why? How can I solve the error?
And What's the difference between these overloaded operator functions and my self-defined function?
//fraction.h
class fraction {
private:
int numerator;
int denominator;
public:
//constrctors
//unary operators
//overloaded operators
friend std::ostream& operator<<(std::ostream& os, fraction target);
...
friend fraction DtoF(const double origin);
...
}
//fraction.cpp
#include"fraction.h"
//other functions
......
fraction DtoF(const double origin) {
int num = int(origin * 1000000);
fraction test(num, 1000000);
test = test.Reduction();
return test;
}
std::ostream& operator<<(std::ostream& os, fraction target)
{
//Simpilfied << function
return os << target.numerator << "/" << target.denominator;
}
Example
#include<iostream>
#include"fraction.h"
using namespace std;
int main(){
cout<<DtoF(5.0);
return 0;
}
Compiler info
~ g++ -c fraction.cpp
~ g++ -c main.cpp
main.cpp: In function 'int main()':
main.cpp:6:10: error: 'DtoF' was not declared in this scope
6 | cout << DtoF(5.0);
| ^~~~
