2. Numeric data

Integer (or int) numbers contain the characters 0-9, possibly prefixed by the unary operators + or -. Examples:

100 -1 +1234

Floating-point (or float) numbers have either a decimal point (.), an exponent (letter e or E, possibly followed by + or -, and followed by 1-3 digits), or both. They may be prefixed by the unary operators + or -. Examples:

0. 1. 123.1 .1 -1e-20 1.234E+2 +0.0002