calculus 1.20

Calculus is advanced calculator with following features:
calculation history list (limited by palm database size)
use of user defined variables and functions in expressions
equation solver with more than 50 equations predefined
built in more than 70 functions (some from Mathlib)
matrix entering and calculations
linear system solving (A x=B)
drop down functions menues
built in unit conversion functions
built in mathematical and physical constants
built in number base conversions (n based)
Sony and Handera HQ display support
simple 2d graph drawing
built in advanced expression parser
Enhancements:
- new equation solver
- increased robustness