How do I put a String into an array and then into an array of double?

Question

Currently I have this:

public class sequence
{
private double[] sequence; 
// set up sequence by parsing s
//the numbers in s will be seperated by commas
public Sequence(String s)
{
  String [] terms = s.split (",");
  sequence = Double.parseDouble(terms);
}
}

What I have does not work. But basically what i am trying to achieve is to move the numerical terms in String s (such as 1,2,3,4,5,6) in an array of double called sequence.

Answer 1

You need to iterate over the terms.

String [] terms = s.split (",");
sequence = new double[terms.length];
for (int i = 0; i < terms.length; i++) {
    sequence[i] = Double.parseDouble(terms[i]);
}

Answer 2

Double.parseDouble take one String and returns one Double . You are passing an array of Strings. Change you code to pass just one String.

public Sequence(String s) {
    String [] terms = s.split (",");
    sequence = new Double[terms.length];
    for (int i = 0; i < terms.length; i++) {
        sequence[i] = Double.parseDouble(terms[i]);
    }
 }

Answer 3

使用Java 8，您可以执行以下操作

double[] sequence = Stream.of(s.split(",")).mapToDouble(Double::parseDouble).toArray();