HistoryCal is a practical calendar calculator designed to work with historical dates. The calculator will convert between different world calendars and work with date ranges.
The HistoryCal Calculator
The HistoryCal calculator will allow you to work with many different world calendar schemes and calculate date ranges and ages based on these calendars. The calculator also has a script language that allows you to create variations of the built-in calendars: calendars that shift the new year to a different day, hybrid calendars that switch between schemes, local observational calendars that depend on a particular location, year counts that change for specific eras (regnal calendars) and calendars that require adjustment due to subtle differences in calculation.
The HistoryCal Project
The goal of the HistoryCal project is to create a reference program, HistoryCal, and a library, the Cal library. The Cal library will manage all the worlds calendar schemes, including all their variations, and allow their use in conversions and calculations. Its aim is to be a tool for historians when transcribing and studying documents and so its focus will be on calenders in the form that they were actually used.
To achieve its aim, the project has been designed with a scripting language. This will enable anyone who has any knowledge or expertise to participate and create calendar variations. The library has the basic calendar schemes built-in and the script will be used to create variations on these, according to how they have been used in practice. Users can add a new calendar variation simply by creating a script. They may then provide this script, with some notes on its use, for use by the wider community.