I'm relatively new to programming and taking a course in C++ currently. I haven't had any major problems so far. I am making a program where an X amount judges can score 0.0 - 10.0 (double) and then the highest and lowest one is removed then an average is calculated and printed out.
This part is done, now I want to read from a file in the shape of: example.txt - 10.0 9.5 6.4 3.4 7.5
But I am stumbling onto problems with the dot (.) and how to get around it to get the number into a double. Any suggestions and (good) explanations so I can understand it?
TL;DR: Reading from file (E.G. '9.7') to a double variable to put into an array.
Answer
Since your textfile is whitespace delimited, you can use that to your advantage by utilizing std::istream objects who skip whitespace by default (in this case, std::fstream):
#include <fstream>
#include <vector>
#include <cstdlib>
#include <iostream>
int main() {
std::ifstream ifile("example.txt", std::ios::in);
std::vector<double> scores;
//check to see that the file was opened correctly:
if (!ifile.is_open()) {
std::cerr << "There was a problem opening the input file!\n";
exit(1);//exit or do additional error checking
}
double num = 0.0;
//keep storing values from the text file so long as data exists:
while (ifile >> num) {
scores.push_back(num);
}
//verify that the scores were stored correctly:
for (int i = 0; i < scores.size(); ++i) {
std::cout << scores[i] << std::endl;
}
return 0;
}
Note:
It is highly recommended to use vectors in lieu of dynamic arrays where possible for a myriad number of reasons as discussed here: