ch-03-ex-01-solution.cpp
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ch-03-ex-01-solution.cpp
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			/*
			* chapter-03-exercise-01.cpp
			*
			* Print to file with a given precision
			*
			* Created on: Sep 2, 2012
			* Author: Radu Popescu <radu.popescu@epfl.ch>
			*/

			#include <iostream>
			#include <fstream>

			int main(int argc, char* argv[])
			{
			double x[4] = {0.0, 1.0, 1.0, 0.0};
			double y[4] = {0.0, 0.0, 1.0, 1.0};

			std::ofstream output_file("x_and_y.dat");
			// Check that file is properly openened.
			if (!output_file.is_open()) {
			std::cout << "Error opening output file." << std::endl;
			return 1;
			}

			// Output in scientific format with 10 significant figures
			// and always showing sign
			output_file.setf(std::ios::scientific);
			output_file.setf(std::ios::showpos);
			output_file.precision(10);
			// Write x vector ending with a new line
			for(int i = 0; i < 4; ++i) {
			output_file << x[i] << " ";
			}
			output_file << "\n";
			// Flush after writing vector x
			output_file.flush();
			// Do the same for y vector
			for(int i = 0; i < 4; ++i) {
			output_file << y[i] << " ";
			}
			output_file << "\n";
			// Flush after writing vector y
			output_file.flush();
			// Close the file when finished
			output_file.close();

			return 0;
			}