FrugalCalc

You decide the price - it's Pay-What-You-Want. Features a multi-line text-editor type of interface 450+ unit conversions built-in with an easy to use interface. Hundreds of functions built-in and ready for use. Save and open your calculation pages with ease. Evaluate built-in and user definable functions, units, constants, and matrices. accurate calculations every time. Calculation Engine: Supports evaluation of complex in-line mathematical expressions; Line referencing (can perform mathematical operations based on previous lines); Evaluation of the Inverse, Prime Factors, and Decimal to Fraction automatically; Ability to solve built-in and user defined functions; Ability to use built-in or user defined constants in mathematical expressions; Standard, Engineering, Scientific, and Financial modes; Tape mode supported for referring to the previous line when performing mathematical operations; All types of Trigonometric functions built-in with Radian and Degree modes; Supports calculating and working with imaginary numbers in Rectangular, Polar, or Rectangular Sum modes; Evaluation of mathematical expressions in number bases 2 - 16 (decimal: 10 is the default); Evaluation of mathematical expressions in different numbers bases (2 - 16) at the same time; Ability to dynamically change the number of Significant Figures used for display Mathematical Operations supported: +, -, *, /, ^, !, , i.

File I/O: Ability to Save CalcPages; Ability to Open CalcPages; Ability to Print Calc Pages (includes Print Preview). Unit Conversions: 450+ commonly used built-in unit conversions; Ability to create user-defined units for use in unit conversions; Base Number conversions (any number base 2 - 16). Additional Features: Matrix Math, Periodic Table, Spreadsheets, Statistics.

Limitations:

Limited features