Java Reference

In-Depth Information

Numbers

Number can be
integers
(whole numbers, such as 3) or
floating point decimals
(often re-

ferred to as just "decimals" or "floats", such as 3.14159). For example:

typeof 3;

<< "number"

typeof 3.14159;

<< "number"

As you can see in the examples above, JavaScript doesn't distinguish between integers and

floating point decimalsâ€•they are both given the type of
"number"
, which is a different

approach to most other programming languages. This is set out in the ECMAScript specific-

ation, although most JavaScript engines will treat integers and floats differently in the back-

ground in order to improve efficiency.

Note: Number Constructor Function

Just like strings, numbers also have a constructor function:

new Number(3)

This is much more verbose than simply writing the number
3
, which is

known as a
number literal
, so it is recommended that you stick to using

number literals.

Octal and Hexadecimal Numbers

If a number starts with a
0x
, it is considered to be in hexadecimal (base 16) notation:

0xAF; // A represents 10, F represents 15

<< 175

Hexadecimal or "hex" numbers are often used for color codes on the Web. You can
read