Double

Overview

Double objects are floating point numbers like 1.5. You can write it in decimal point notation.

Methods

There is a special object named as Double. The methods of Double can be used for integer values directly.

Method	Meaning
Double.toString(val, format)	Converts val into a string. format can be a, A, e, E, f, F, g, or G following %. %g will be used if omitted.
Double.toInt(val)	Converts val into Integer.

The Double object can hold any methods you want to add. For example, see below.

Double.times100 = function(value) {
    return value * 100;
};
var val = 100.2.times100();
System.println(val);

Let’s run it.

10020

The receiver comes in the first argument.

Math Object Method

Double objects have the same special methods as Math objects. See below for details. When written in a concrete example, the following can be written, for example.

var a = 2.0.pow(10); // same as Math.pow(2.0, 10) => 1024
var b = (-10.0).abs(); // same as Math.abs(-10.0) => 10

Note that unary minus (-) has lower precedence than function calls, so it must be enclosed in parentheses.

Examples

Example 1. Normal case

Code

System.println(100.1);

Result

100.1

Example 2. Math

Code

var a = 2.0.pow(10);
var b = (-10.0).abs();
System.println(a);
System.println(b);

Result

1024
10