accessing data within array of structure in C++ - c++

Question

This is an assignment that required me to use ifstream to stream a CSV file. this csv file contains 52 state names and amount of different resources used by each state. for example:
Alabama,410.20,715.70,169.40,18.00,44.90,309.10,11.90,417.30,64.50,167.40,23.70,0.10,0.40,0.00
then I need to prompt the user to type the state name and the output is the percentage of resources used.
I created a struct containing a string type and an array to store the value of each state and created an array of struct to store multiple state's data, but I am not sure whether my code is right, and I want to know how to access other data, such as the data store in my double array, when the user input a state name.
here is my code:
struct statData
{
string statename;
double StatDataNumber[14];
}DataStruc[51];
int main()
{
ifstream indata;
string line;
statData State;
State.statename;
statData Consumption;
Consumption.StatDataNumber;
indata.open("Data2016.csv"); //opening file
if (indata.fail()) //fail safe
{
cout << "Fail to open file";
exit(1);
}
getline(indata, line); //skipping the first line of the csv file
int i;
int N = 0;
int NLoop;
int Loop = 0;
string InvertValueBefore;
double InvertValueAfter;
char comma;
while (indata.eof()) // before file reache the end
{
for (NLoop = 0; NLoop < 51; NLoop++) // struct array loop
{
{
getline(indata, DataStruc[Loop].statename, ',');// getting statename
for (i = 0; i <= 12; i++) // each group of data, except last
{
indata >> DataStruc[Loop].StatDataNumber[N] >> comma;// storing data in struct
N++;
}
getline(indata, InvertValueBefore); // store last value as string
InvertValueAfter = stoi(InvertValueBefore); // convert it into double
InvertValueAfter = DataStruc[Loop].StatDataNumber[N]; // store it in array of struct
}
Loop++;
}
}
ReadData();
return 0;
}
void ReadData (ifstream& indata , statData DataStruc[] )
{
int i;
string input;
bool stayinloop = true;
cout << "Enter a statename or 'q' to quit\n";
getline(cin, input);
while (stayinloop == true)
{
if (input == "Alabama")
DataStruc[i].statename == "Alabama";
DataStruc[i].StatDataNumber[]
}
}
this code is not finished. Please let me know if you spot any other error. Thank you!

Answer 1

Your code is fine. However, certain points:
1. You just need to get rid of certain variables which are not required.
2. The "eof" function is used to identify if the end of file is reached. For which, you need to use while (!indata.eof()).
3. The "ReadData" method should appear before the main function, however, if you want to have your functions after the main function then first you need to define your function declaration before the main function (i.e. before main function, you can put "void ReadData (ifstream& indata , statData DataStruc[]);"), afterwards you can define your function.
Below is a working version of your requirements.
#include <iostream>
#include <string>
#include <fstream>
#include <stdlib.h>
using namespace std;
struct statData
{
string statename;
double StatDataNumber[3];
}DataStruc[2];
void ReadData (ifstream& indata , statData DataStruc[])
{
string input;
bool stayinloop = true;
while (stayinloop)
{
cout << "\nEnter a statename or 'q' to quit\n";
getline(cin, input);
for (int i = 0 ; i < 2; i++)
{
if (input == DataStruc[i].statename)
{
for(int j = 0 ; j < 3; j++)
{
cout << DataStruc[i].StatDataNumber[j] << ',';
}
}
else if(input == "q")
{
stayinloop = false;
}
}
}
}
int main()
{
ifstream indata;
string tempData = "";
string line;
string InvertValueBefore = "";
double InvertValueAfter = 0.0;
char comma = ',';
indata.open("test.csv"); //opening file
if (indata.fail()) //fail safe
{
cout << "Fail to open file";
}
getline(indata, line); //skipping the first line of the csv file
while (!indata.eof()) // before file reach the end
{
for (int NLoop = 0; NLoop < 2; NLoop++) // struct array loop
{
{
getline(indata, DataStruc[NLoop].statename, comma);// getting statename
for (int i = 0; i < 2; i++) // each group of data, except last
{
getline(indata, tempData, comma);
DataStruc[NLoop].StatDataNumber[i] = atof(tempData.c_str());
}
getline(indata, InvertValueBefore); // store last value as string
InvertValueAfter = atof(InvertValueBefore.c_str()); // convert it into double
DataStruc[NLoop].StatDataNumber[2] = InvertValueAfter;
}
}
}
ReadData(indata, DataStruc);
return 0;
}