Formula Input Order

DreamCalc Pro supports two styles of algebraic input, standard order and text book order. You can easily set the input mode to the one you feel comfortable with, using either the 'Modes' menu option, or the [MODE] key.

Standard Order

In standard order (sometimes referred to as traditional order), equations are entered in the same way as you would when using the calculator in Windows. In this mode, mathematical operations are generally executed the moment you press a function key. For example, if you wanted to enter the equation:

sin(60) + cos(30) =

you would need to enter the following sequence:

[6] [0] [sin] [+] [3] [0] [cos] [=]

Text Book Order

Most modern scientific calculators use text book order (sometimes referred to as true order). This means that equations are entered into the calculator the way they are written. For example, with the equation:

sin(60) + cos(30) =

you would need to enter:

[sin] [6] [0] [+] [cos] [3] [0] [=]

Quite often with text book order, you find yourself needing access to the result of your previous calculation, and the [Ans] key comes in useful for this.

More About Input Order

As a general rule, unary functions (such as sin, cos, log10 etc.) are affected by changing the input order, while binary operators and functions, (i.e. +, -, x^y, logb etc.) are not. There are exceptions of course, such as x² which is unary, but does not change behaviour because of the way it is written.

A note from DreamCalc's Author: "Until the late 1980s, early 90s, most scientific algebraic calculators used 'standard order' input. Now, however, most scientific calculators use 'text book order' input. I would guess the input order you prefer depends on when you began using a calculator. Personally I find standard order better if I am 'thinking on my feet', but text book order makes sense when entering a number of equations from a page."