Loading data into a vector from text-file

Hi

I use the following piece of code to load a bunch of doubles into my vector:

Code:

---

#include <iostream>
#include <fstream>
#include <vector>

...


        std::vector<double> velX;
        double velTemp;

        std::ifstream vX("vX.txt");
        if(vX.is_open())
        {
                while(!vX.eof())
                {
                        getline(vX, velTemp);
            velX.push_back(velTemp);
        }
                vX.close();
                }
        else
        {
                cout << "Unable to open file." << endl;
    }

---

However, my compiler says that getline is "an undeclared identifier". Isn't that what iostream is supposed to contain?

Best,
Niels.

The getline() functions only work with C-strings, or std::string not doubles, try the extraction operator>>. Also you should not use eof() to control your entry loop as this will usually cause problems, use your extraction operation. This link may be of some interest: Basic C++input and output

Jim

Quote:

---

Originally Posted by jimblumberg

The getline() functions only work with C-strings, or std::string not doubles

---

The istream member function getline() only works on C-strings. The free function getline() from <string> works with std::strings.

OP: neither getline reads doubles, so as jimblumberg pointed out the extraction operator e.g. while(vX >> velTemp) is the way forward.

Thanks to both of you,

Best.