text: // This program uses the setprecision and fixed
  // manipulators to format file output.
  #include<iostream>
  #include<iomanip>
  #include<fstream>
  using namespace std;
  
  int main()
  {
  	fstream dataFile;
  	double num = 17.816392;
  
  	dataFile.open("numfile.txt", ios::out);		// Open in output mode
  
  	dataFile << fixed;				// Format for fixed-point notation
  	dataFile << num << endl;		// Write the number
  
  	dataFile << setprecision(4);	// Format for 4 decimal places
  	dataFile << num << endl;		// Write the number
  
  	dataFile << setprecision(3);	// Format for 3 decimal places
  	dataFile << num << endl;		// Write the number
  
  	dataFile << setprecision(2);	// Format for 2 decimal places
  	dataFile << num << endl;		// Write the number
  
  	dataFile << setprecision(1);	// Format for 1 decimal place
  	dataFile << num << endl;		// Write the number
  
  	cout << "Done.\n";
  	dataFile.close();				// Close the file
  	return 0;
  }