number of periods (custom) between two dates
<p>I want to find out how many periods (custom) are there between two dates. Like how many weeks are between 1 july to 2nd Aug or how many half months are there between 2 nd Juy and 14 Dec, where in half month would be customizable whether it ends on 15th or 16th. </p>

<p>IS there any library where this or something similar has been done? Not that its tricky but just want to know if such things exists.</p>
