Calcul-8! freeware for Palm OS by David E.H. Griffiths

Main features
Why I wrote it
Float and Integer Modes
Numerical Input
Simple Calculations
Trigonometric Functions
Other Maths Functions
Float Preferences
Memory Stores
Integer Modes
Unit Conversions and Constants
Button Preferences
Revision History

Main features:


Why I wrote it

The calculator provided by Palm is woefully inadequate for all but the most basic of tasks. Also, there does not seem to be a free/shareware calculator around that is fairly decent, fairly compact, and fairly fast to operate. There are a few that are not bad, but they are generally slow to operate due to the refusal to put more than about 5 or 6 buttons on the screen at one time. Graffiti™ is ok, but it's much faster to tap buttons.

I also wanted a calculator that has good support for unit conversions, and a good Base-n integer mode. I've always been used to the standard cheap Casio calculators, so I haven't gone for a reverse polish mode of input, or a style where you type in an expression and hit execute. If you prefer these modes of input then sorry, perhaps I'll add it in the future.


Float and Integer Modes

At the top right of the screen are 5 buttons, . These are to switch between Float, Hexadecimal, Decimal, Octal and Binary modes. Float mode is for all floating point calculations. i.e. anything that requires a decimal point. Hex, Dec, Oct and Bin modes are all Base-n integer modes. You can switch freely between all modes, but be aware that switching from float mode to an integer mode will truncate fractions, and large numbers may overflow the integer representation.


Numerical Input

You can enter numbers one of two ways. Either by pressing the buttons, or by using Graffiti™. There are 16 digit keys, . Which of these digits can be used depends what the current mode is. The digits that can be used are shown in bold.

In addition there are some other buttons for number input and display:

decimal point
exponent (e.g. for numbers such as )
change sign (if editing the exponent, changes the sign of exponent)
back space to undo the last digit pressed
recall result of previous calculation
all clear - clears display and all buffered input for the current calculation
clear - clears the display
changes exponent display in multiples of 3


Simple Calculations

To calculate 5+6, press .

To calculate 5x(2+4) you have to take note of operator precedence. Either type , or make use of the bracket buttons and type .

Note that by pressing again will repeat the last operation, so in the last example pressing will multiply by (2+4) again.


Trigonometric Functions (float mode only)

Before performing any trigonometric functions you must be aware which angle mode you are in. The current angle mode is shown below the digit display on the right hand side (assuming you are in float mode).

There are three angle modes:

degrees (right angle = 90°)
radians (right angle = pi/2)
grads (right angle = 100)

To switch between angle modes, bring up the Float Preferences dialog. To do this either tap on the angle symbol, or go to Menu->Options.

To calculate sine of 90° (degrees), change to degree mode and type .
To calculate the inverse cosine of 0 type .
To calculate the hyperbolic tangent of pi type .
To calculate the inverse hyperbolic sine of 5 type .


Other Maths Functions

Other maths functions are:

reciprocal (only available in float mode)
square
square root
power y
power 1/y
factorial
permutation
combination
log base 10 (only available in float mode)
inverse log (only available in float mode)
ln (natural log) (only available in float mode)
inverse ln (only available in float mode)
modulus
pi
random number from 0 to 32767  (in integer mode this is mod the highest representable number)

Examples:

1/4 = = 0.25
3 squared = = 9
49 square root = = 7
5^3 = = 125
Permutations of 2 in set of 3 = = 6
e^1 = = 2.718281828459
8 mod 5 = = 3

Float Preferences

The float preferences dialog can be reached via the menu, or by tapping on the area of the display under the digits when in float mode, that shows the current angle and float mode.

There are 4 Float Modes:

ModeDisplay TypePrecision Meaning
Normal exponential notation maximum number of decimal places
Fixed fixed decimal places number of decimal places
Scientific scientific notation number significant figures
Engineering exponent in multiples of 3
f=-15, p=-12, n=-9, m=-3, k=3, M=6, G=9, T=12
maximum number of decimal points


Memory Stores

There are 26 memory stores, named A-Z. Memory store M is mapped to the following keys:

Clear memory store M
Recall memory store M
Store in memory store M
Add to memory store M
Subtract from memory store M

All memory stores are accessible via the buttons for store and recall.

Note that the memories are displayed using the current number mode and preferences.


Integer Modes

There are four integer modes: Hexadecimal, Decimal, Octal and Binary. To switch between these use the buttons at the top of the screen , but be aware that switching from float mode to an integer mode will truncate fractions, and large numbers may overflow the integer representation.

In Hex and Binary modes the digits are grouped for ease of reading. In Binary mode the digits may not fit into the display and are shown in two halves.

In an integer mode, 6 different buttons are displayed for performing logical operations. These are .

Examples:

5 AND 3 = = 1
9 >> 1 = = 4
Not/complement of 1 = = -2 or FFFF FFFE in hex mode

In integer modes the bit width can vary between 8, 16 and 32 and the mode can be signed or unsigned. The bit width is shown beneath the digit display.

You can change the bit width or sign mode via the menu or by tapping the bit width indicator


Unit Conversions and Constants

Calul-8! has over 100 built-in unit conversions in the categories Area, Distance, Energy, Mass, Power, Pressure, Speed, Time, Temperature, and Volume. Conversions are quick and easy to perform in either direction. To perform a conversion, use the button. This brings up a menu from which can be used to convert between two units, and to change the current conversion pair.

Tapping the "Change..." item will bring up a dialog that will let you select the pair between which you wish to convert.

The factor that will be used is displayed here also which is useful if, for example, you just wish to know how many kms there are in a mile. The button swaps the pair of units around, so in the example the factor will change to the number of miles in a km. Note that no factor is applicable for Temperature conversions.

To access over 30 commonly used scientific constants, tap the K button at the top of the screen. This brings a drop down list of constants.


Button Preferences

You can configure the look of Calcul-8! by choosing from a range of button designs.

Digit buttons can be changed independently from standard buttons. Only digit buttons currently active use this button design, and the active digits buttons depend upon the mode.

For black button designs, you may wish to use bold text for the standard buttons to ease clarity.


Revision History

Version 1.1.0 - 23rd Mar 2002

Version 1.0.2 - 28th Feb 2002

Version 1.0.1 - 25th Feb 2002

Version 1.0.0 - 20th Feb 2002