Calcula was originally created in 1986 as a personal utility for the BBC Micro. The objective was to produce a simple tool to do the type of calculations I required, both as a BASIC programmer and for simple statistical use. Feel free to expand it to suit your needs.
The desktop version is my first attempt at getting properly to grips with Wimp programming, and is functionally the same as the BBC version, except that it multitasks.
In essence, you can type in any BASIC expression capable of being evaluated by EVAL. All normal arithmetical and trigonometrical expressions will work. One or two other functions were added as needed.
It only knows its own variables, and of these, only X, M1,M2 and M3 are relevant to users.
X is the variable which holds the numeric result of a calculation.
M1,M2,M3 are 'Memories' to hold these results. To load memory, type M1=X into the argument line and the last result will appear in the M1 field. The same applies to M2 and M3. You can also type in things like M3=M1+M2.
The program will also help with hex, binary and decimal conversions.
| Conversion | Example | Result
|
|---|---|---|
| Binary to Decimal | %10101 | 21
|
| Decimal to Binary | BIN123 | %111011
|
| Hex to Decimal | &FF | 255
|
| Decimal to Hex | ~255 | &FF
|
You can also type, for example, ASC"A" into the argument line, and get back 65 as the result. If you type in CHR$65 you will also get back "A".
Typing a series of numbers separated by commas will result in the average (arithmetic mean) when return is pressed.
| Series | Result
|
|---|---|
| 12,13,14,15,16 | 14
|
Prefix the series with SDEV and the result will be the value of one Standard Deviation.
| SDEV12,13,14,15,16 | 1.414213562
|
I have now put in VAT calculations at 17.5%. These can be entered in two ways, depending on whether VAT has to be added, or extracted from an amount:
| Example | Result
|
|---|---|
| VAT+125 | £125.00+£21.88VAT=£146.88
|
| VAT-125 | £106.38+£18.82VAT=£125.00
|
Non fatal errors will be reported if you make a mistake, and allow you to resume.
I hope you will find this program useful. Please, when you pass it on ensure that all the contents including this 'readme' are present. If you modify it and pass that on, add your additional features here - and don't forget to credit yourself!
Version 2.06 involved a complete replacement of the WIMP routines.
Originally passed into the Public Domain via APDL, way back when Peter Sykes ran it.