Arity Calculator was written by Mihai Preda, and is open source. It uses the "Arity" arithmetic library. Адаптировано для Android 4. X by Naik. Special mod for KI-14-1: ) Enjoy! Sample expressions. Simple expression: 1+2. Variable evaluation: pi. Function evaluation: sin Variable definition: a=3. 5. Function definition: f =x^2-1. Parentheses: ^2.