CalcBoard
by Tiksi Labs

  The next step in calculations. Calculate expressions using units and interval arithmetic.
The CalcBoard is a straightforward utility to construct and estimate expressions. It supports:Numeric values with units and calculations using units; Values with errors and interval arithmetics; A wide range of standard functions; Easy (calculator-like) interface; A set of persistent variables to assign expressions to, Syntax highligh, tSaving a calculation to a file.
Using CalcBoard you can execute complex multistage calculations and even write simple programs without programming.

Related software:
interval arithmetic, fuzzy values, automatic unit conversion, ...