import java.io.*;

class data {

public static void main(String args[]){

try{

File r = new File("data.csv");

FileWriter pw = new FileWriter(r);

PrintWriter pr = new PrintWriter(pw);

pr.println("x,y");

pr.println("0.1,1");

pr.println("1.2,2");

pr.println("2.3,1.5");

pr.close();

} catch(IOException e) {}

}

}