Decimal numbers

A decimal number consists of a sequence of digits, followed by an optional fraction, followed by an optional exponent. The fraction consists of a decimal point (.) followed by a sequence of digits; the exponent consists of an e or E followed by an optional + or - sign and a sequence of digits. A decimal number must have at least one digit.

Here are some examples of decimal number literals:

15
3.14
4e100
.25
5.25e-10