Regular expression for restricted signed number formats

Question

I want a regex for the following given pattern:

{anynumber} will return true.

+{anynumber} will return true.

-{anynumber} will return false.

{anynumber}.5 OR {anynumber}.50 OR {anynumber}.500 and similar pattern will return true (i.e. any number of zeros after .5).

+{anynumber}.5 / +{anynumber}.50 / +{anynumber}.500 and similar pattern will return true.

-{anynumber}.5 / -{anynumber}.50 / -{anynumber}.500 and similar pattern will return false.

+{anynumber}.6 / +{anynumber}.75 / +{anynumber}.205 and similar pattern will return false (i.e. after decimal point only 5 is allowed at the first place with any or no number of zeros afterwards).

No limitations of length of numbers.

Answer 1

Here you are:

^(?:(?: \/ )?[+]?[0-9]+(?:\.50*\b)?)+$

And here is a demo.