Open Source Calculators

HistoryCal is a practical calculator designed to work with historical dates and calendars. The calculator will allow you to work with many different world calendar schemes and calculate 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.

This calculator will allow you to convert between many different world calendar schemes and calculate 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.

Calculators became available in the early 70's, soon after the integrates circuits, and several companies were competing with each other for a share of this market. Texas Instruments was one of the bigger companies producing calculators. With RCL it is possible to recreate the TI calculators, strating with the Ti59e, with 960 program steps and a persistant memory (a combination of the the Ti58C and the Ti59). RCL offers any person interested in the ancient ones in calculators (more specific: TI calculators) an option to have your old calculator under your control again. Looking for user manuals? go to http://www.rskey.org/CMS/index.php/the-library/12 (The site owner does a great job at preserving the history and the documentation of calculators of the period.) RCL is targetting developers interested in applying the Von Neumann architecture and attributed grammars and developers with a need to do complex calculations in their applciacation.

Java software for computing seats distribution in a proportional voting scenario. D'Hondt, Saint-Lague and Hare-Nimeyer. For more info: https://sites.google.com/site/pubredi/social-choice/seats-calculator

RPowr is a simple calculator for planning correlational research. It computes the power of the Pearson correlation coefficient allowing adjustment for unreliability and range restriction of the variables (e.g. predictor and criterion measures).