regex for single precision decimal or non decimal number between a range code example

Example 1: regex validate double with 2 decimals

^(\d+(\.\d{0,2})?|\.?\d{1,2})$

Example 2: number between 0 and 5 with decimals regex

[+]?([0-4]*\.[0-9]+|[0-5])

Validates a number between 0 and 5 including decimals