CALC 1 Home Documentation Home Contact

Calculation Methods Used by CALC 1

CALC 1 supports chain (CHN), algebraic expressions (ALG)  and Reverse Polish Notation (RPN) calculation methods. The calculation method can be set in the Options.


Chain mode is the default system for many business and financial calculators. Good for basic to moderate calculations since each operation is executed immediately. Undo is available for every operation to make it easy to recover from mistakes. You can also use the automatic stack in chain mode.

2+3×4 = 20.00. 5.00 will be displayed after tapping ×.
Use parenthesis for, 2+(3×4 = 14.00

498+7% will display 498.00+34.68 after tapping the % key. 532.86 will be displayed after tapping =.

See Calculations Using the Chain (CHN) Calculation Mode for examples of the chain method.


The CALC 1 algebraic mode  expressions are similar to expressions in spreadsheets and scientific calculators with order of operation that spreadsheets and computer languages use in evaluating expressions.

2+3*4 = 14.00
(2+3)*4 = 20.00

The expression is in a separate area than the results so you can view the entire expression that produced the results. The expression is executed when you tap "=". This is good that you can view the  expression but the disadvantage over chain and RPN is that undo is not available for every operation.

Expressions can be made into custom keys and Function Calculators automatically using the "Create Key" and "Create Fn" buttons in the History Details. This powerful feature reduces errors and saves time.

See Calculations Using Algebraic Formulas for examples of the algebraic method.

Reverse Polish Notation

Reverse Polish Notation (RPN) is used on many HP scientific and financial calculators. It is an efficient, parenthesis free system. Undo is available for every operation to make it easy to recover from mistakes.

2+3×4 can equal 20 or 14 depending on how the user enters the values and operators.
2 ENTER 3 + 4 × will equal 20.00
2 ENTER 3 ENTER 4 × + will equal 14.00

For percentages, 498, ENTER, 7 % will display 34.68. Then tapping + will display 532.86.

See Calculations Using RPN and the Stack for examples of the RPN method.

See the Wikipedia page, Calculator input methods for more information.