No predefined constructor existing C++ - c++

Question

I have been spending hours on this but I can't seem to find a solution to this problem.
I have am working with two header files, one is Load.h and one is Source.h.
This is my load.h:
#ifndef LOAD_H
#define LOAD_H
#include <string>
#include "Complexnumbersfrompreviousweek.h"
#include "Otherfunctionsfrompreviousweek.h"
#include "Source.h"
class Load : public Source //I'm doing this to inherit the vs term
{
private:
double load;
double vload;
double ApparentP;
public:
Load (double, double, double, double);
double Calcvload (double, double, double, double);
};
#endif LOAD_H
This is my Source.h:
#ifndef SOURCE_H
#define SOURCE_H
#include <string>
#include "Complexnumbersfrompreviousweek.h"
#include "Otherfunctionsfrompreviousweek.h"
class Source {
public:
double vs;
Source(double);
double Ret(double);
};
#endif SOURCE_H
And this is my second .cpp file:
#include "Line.h"
#include "Load.h"
#include "Source.h"
#include <fstream>
#include <string>
#include <sstream>
#include <algorithm>
#include <iostream>
#include <math.h>
using namespace std;
Source::Source(double VoltageS)
{
VoltageS = vs;
};
double Source::Ret(double vs)
{
return vs;
}
Load::Load(double VoltageS, double Sl, double Z, double Vl)//Constructor
{
Z = load;
Sl = ApparentP;
Vl = vload;
VoltageS = vs;
};
The error I get is error C2512: 'Source' no predefined appropriate constructor available.
This is what I am doing in my main():
Source Sorgente(VoltageS);
Load loadimpedance(VoltageS, Sl, Z, Vl);
So basically I am creating the "Sorgente" object using VoltageS as an argument (selected by the user, I didn't put that bit of code in) and I am trying to assign it to Vs in order to use it in the constructor for the Load afterwards...
Thank you in advance for your help!

Answer 1

Since Load inherits from Source, it has to construct the Source base in its constructor:
Load::Load(double VoltageS, double Sl, double Z, double Vl)//Constructor
{
Since you don't explicitly specify one, the compiler will automatically insert the default:
Load::Load(double VoltageS, double Sl, double Z, double Vl)//Constructor
: Source() // implicitly inserted by compiler
{
But that constructor doesn't exist - hence the error. To fix this, you need to explicitly call the correct constructor:
Load::Load(double VoltageS, double Sl, double Z, double Vl)//Constructor
: Source(VoltageS) // explicitly construct the base
{
Unrelatedly, in your Source constructor you are assigning the wrong element:
Source::Source(double VoltageS)
{
VoltageS = vs; // you are assigning to the temporary instead of your member
}
That should be:
Source::Source(double VoltageS)
: vs(VoltageS)
{ }