type mismatch: can't convert from double to int java

Question

public static void main(String[] args) {
try{
    BufferedReader br=new BufferedReader(new FileReader("file.txt"));

    String[] pole=br.readLine().split(" ");
    double L=Double.parseDouble(pole[0]);
    double N=Double.parseDouble(pole[1]);
    String[] weight=new String[N];
    double[] scale=new double[N];
    double[] place=new double[N];
    for(int i=0; i<N; i++){
        weight[i]=br.readLine();
        String[] variable=weight[i].split(" ");
        double variable1=Double.parseDouble(variable[0]);
        double variable2=Double.parseDouble(variable[1]);
        scale[i]=variable2;
        place[i]=variable1*variable2;               
    }

I have this java code. I Want to get the number from the file and convert them into double, but it gives me that error: type mismatch: can't convert from double to int. How can I fix this?

Solution 1

Since N is double You need a type case there

String[] weight=new String[(int)N];

The reason is double is a floating point type and you cannot create an array of length 1.5 :)

Solution 2

Try with this

public class Tuple {

    public static void main(String[] args) {
        try{
            BufferedReader br=new BufferedReader(new FileReader("UserController.txt"));

            String[] pole=br.readLine().split(" ");
            double L=Double.parseDouble(pole[0]);
            double N=Double.parseDouble(pole[1]);
            System.out.println("L is "+L);
            String[] weight=new String[(int) N];
            double[] scale=new double[(int) N];
            double[] place=new double[(int) N];
            for(int i=0; i<N; i++){
                weight[i]=br.readLine();
                String[] variable=weight[i].split(" ");
                double variable1=Double.parseDouble(variable[0]);
                double variable2=Double.parseDouble(variable[1]);
                scale[i]=variable2;
                place[i]=variable1*variable2;               
            }
        }
            catch(Exception e) {
                e.printStackTrace();
            }
    }
 }

Comments

[Antoniossss]

And why would you want to truncate your data insteed of rounding it?

[Suresh Atta]

@Antoniossss True, but there is no point to rounding. I never create an element if the value 0.9 or 0.51 :) Both are same in this case.