how to define and declare although it is defined and declared? - c++

Question

i know the question looks confusing but truthfully it isn't like it seems.
im building a programme about drone ( sorry if it doesnt make sense)
Here from this code i get error "(line 116 )identifier "camrecord" is undefined " and "Compiler Error C2065
'(line 116) identifier' : undeclared identifier" although i already identify and declare them? how to solve this?
thank you
#include<iostream>
#include <fstream>
#include <cstdlib>
#include <iomanip>
#include <string.h>
using namespace std;
void manualMode();
void defaultMode();
void Getdata(double & camrecord, double & Projectframerate);
void calculate(double & camrecord, double & Projectframerate, double & actualframerate);
int speed, timeTofly, operation;
int angle = 90;
int main() {
int mode = 0, part = 3;
double flyLevel;
int obstacleSensor = 0, timer = 3, AccelerometerSensor = 0, tempSensor = 25;
char startPause;
cout << "Drone Flying Technology" << endl;
do {
cout << "Choose Mode: (1)Default, (2)Manual \n";
cin >> mode;
if (mode == 1)
defaultMode();
if (mode == 2)
manualMode();
} while (mode == 0);
cout << "Choose how to fly: (1)Upper , (2)Lower , (3)Upper and Lower \n";
cin >> part;
switch (part) {
case 1:
case 2:
flyLevel = 0.5;
break;
case 3:
flyLevel = 1;
break;
}
if (obstacleSensor == 0) {
do {
cout << "Press (S) to Start,and swing the propeller." << endl;
cin >> startPause;
cout << "LED is On\n";
while (AccelerometerSensor != flyLevel) {
AccelerometerSensor++;
}
cout << "Flying session Started! Time Left:" << timeTofly << endl;
cout << "Eagle eye Operation Started!\n";
timeTofly = timeTofly / 2;
cout << "Crusing mode initiate Time Left:" << timeTofly << endl;
timeTofly = timeTofly / 2;
cout << "Free fly commenced Time Left:" << timeTofly << endl;
timeTofly = 0;
startPause = 'P';
} while ((startPause == 's') || (startPause == 'S'));
}
cout << "End!\nLED is Off";
return 0;
}
void manualMode() {
cout << "Enter drone speed (knot) \n";
cin >> speed;
cout << "Enter Time to fly: \n";
cin >> timeTofly;
cout << "Choose Operation: (1)Fully manual, (2)Normal Orientation, (3)Free orientation, (4)FPV racing, (5)All\n";
cin >> operation;
}
void defaultMode() {
int howtofly;
cout << "how to fly: (1)Circle, (2)Altitude Hold, (3)Free orientation";
cin >> howtofly;
switch (howtofly) {
case 1:
speed = 30;
timeTofly = 3;
break;
case 2:
speed = 40;
timeTofly = 3;
break;
case 3:
speed = 60;
timeTofly = 3;
break;
}
char name[25];
char id[5];
float m1, m2, m3, m4, m5;
ofstream outputFile("droneinfo.txt", ios::out);
cout << "Please enter object you want to record,drone id imei number and your 5 preferred video fps:\n";
cout << "\nPress <ctrl> + z to stop. \n";
while (cin >> id >> name >> m1 >> m2 >> m3 >> m4 >> m5)
{
outputFile << id << " " << name << " " << m1 << " " << m2 << " " << m3 << " " << m4 << " " << m5 << endl;
}
double fps = 0.0;
double Projectframerate = 0.0;
double actualframerate, out = 0;
Getdata(camrecord, Projectframerate);
calculate(camrecord, Projectframerate, actualframerate);
cout << "The actual frame rate is =" << actualframerate << " f/s\n";
}
void Getdata(double& camrecord, double& Projectframerate) {
cin >> camrecord;
cin >> Projectframerate;
cout << "Please enter\n Recording frame rate =" << camrecord << "f/s ,\ndesired frame rate="
<< Projectframerate << "f/s\n";
}
//-------------------//
void calculate(double& camrecord, double& Projectframerate, double& actualframerate) {
actualframerate = camrecord / Projectframerate;
}
//-------------------//

Answer 1

So a reference as an argument is used when you want to input a variable and modify it. Looking at void Getdata(double& camrecord, double& Projectframerate), you are saying that Getdata takes a camrecord and a projectframe rate, reads these value and modifies them, so that the caller can use the new values.
Looking at the code, it does not seem Getdata is actually reading the input values. So there is an inconsistency.
To be consistent with the implementation of the method, the method Getdata should not take any arguments - but only return them. Now, you cannot return two arguments, but you can pack them into a struct and return that:
struct Data
{
double camrecord;
double Projectframerate;
};
Data Getdata();
The definition of Getdata can then be:
Data getData()
{
Data data;
cin >> data.camrecord;
cin >> data.Projectframerate;
cout << "Please enter\n Recording frame rate =" << data.camrecord << "f/s ,\ndesired frame rate="
<< data.Projectframerate << "f/s\n";
return data;
}
Similarly can be done for calculate.