Kalk is a simple RPN calculator, with a 20-level stack, that knows the four basic operations plus some trig and log functions.
Design Goals
There are lots of desktop calculators out there. Why one more? I made this one for my own personal use, because I wanted a RPN calculator, but not that huge monsters I’ve seen around, almost complete implementations of scientific HP machines. Those were great calculators, but they filled almost the whole screen with tens of buttons and switches. At the end of one week I usually was back to the classic Apple calc, because it’s small, fast, doesn’t create auxiliary files on the disk, and doesn’t have big manuals.
So, the first goal on Kalk design was to make its window the same size of Apple’s. Then remove all digit buttons from the panel, making area for more information (six of the 20 levels of the stack are shown). The only buttons remaining are those used everytime and those that are hard to remember without a label. Digits are entered via the keyboard, and the special functions are grouped on the “Kalk” menu.
Using Kalk
Using Kalk is very like doing simple math on a 28- or 48-series HP calculator. As for the Apple calc, the numeric keypad of your keyboard (hope you have one) is the best choice. When you type digits, the Edit Line (E:) is turned on. You can use it like any Macintosh text field, using arrows, selecting, deleting, copying, cutting, pasting, etc. When you press Enter the Edit Line is turned off and its contents are pushed into the stack. As with HP calculators, you don’t need to press Enter all the times; if you use an operator in edit mode, Enter is pressed automatically for you.
Operation (Keyboard Shortcuts and Hidden Features)
(these shortcuts are available online while using Kalk; look at the “?” Menu)
• +, -, /, *: the basic four operators are used directly from the keyboard
• Enter: you can press Return, or Enter on the keyboard
• Swap: you can use the = key
• Drop: you can use Option-= or Delete (Delete only works as Drop if the edit line is empty)
• CHS: you can use Option-<minus>
• Clear: you can use the Clear key, or Esc, or “Clear” on the “Edit” menu
• π: you can enter an approximation of π by pressing p, P, π , or ∏. This may be useful for trig calculations, since sin and cos on the Kalk menu are performed with degrees (not rads).
• The “E:” on the Edit Line changes to red boldface when there are less than five free levels on the stack.
• “Edit First Line” (Command-E) puts the first line of the stack into the edit line.
• If you press Enter with an empty edit line, the current first level is duplicated (Dup).
• Copy and Cut puts the contents of the first level only into the clipboard.
• Paste is quite different. It actually “plays” any text that’s in the clipboard through the same general input procedure, just as if it was being typed. You can copy a list of values (separated by “returns”) from a text editor or spreadsheet and paste into Kalk: the values will be entered into the edit line, and the “returns” will be interpreted as Enters, filling the stack automatically. Bad digits (not valid numbers) will be filtered out, the same way they are when you type. If there are Kalk special characters in clipboard text (+, -, /, *, π, ≠, =, option-<minus>) they will be interpreted also, making Kalk minimally “programmable” in RPN form.
• Kalk remembers the stack and window position after Quit, unless you lock the application file.
• You can change Kalk’s background texture on the “Desktop Patterns” Control Panel (System 7.5 or higher only). Just open the control panel, select a pattern and press the Option key to change the button from “Set Desktop Pattern” to “Set Utilities Pattern”. This will change the background of most Apple utilities (Key Caps, Calculator, Find File, etc.).
• The beep sound can also be changed. Just add a System 7 sound file named “Kalk Beep” to your System suitcase.
Kalk is free. Please drop a note to say something about it, including bugs and suggestions.
New versions and platforms! See the web page for more information.
I'm porting Kalk to several different hardware platforms. There may be a Unix Kalk (for Unix text-based consoles and telnet sessions), a Windows Kalk and a X-windows Unix Kalk for some Unix boxes (SunOS, Solaris, Silicon Graphics, IBM AIX). This is quite a work to do, but it is coming out.
I've prepared some web pages to gather information about Kalk in general. If you're interested, please go to http://godel.lmf-di.puc-rio.br/Staff/Terra/kalk/kalkHome.html and look. I've attached a HTML file to the Kalk release, so you can simply open the "Visit Kalk Home.html" file in your WWW browser instead of typing this enourmous string.
Version History
1.0ß1 First public release
1.0 Not released
1.0.1 Included the ability to enter negative exponents. Two other small bugs on "Paste" corrected. Please note that characters in text to be pasted are interpreted just like typed ones, so negative exponents must be written with option-minus. Added a “Kalk Shortcuts” menu item and dialog, in the Help/Guide menu.
1.0.2 and 1.0.3 not released (their bugs were corrected (I hope) in 1.0.4
1.0.4 Added a gray background and 3-D looking buttons. These are the original 1.0 Beta Kalk buttons, and their code allow interesting future developments. Kalk no longer looks different under Greg’s Buttons. Kalk no longer beeps when the Help/Guide menu is hidden or missing in the host system.
1.0.5 Added boldface to the red near-full alarm, so it can be seen on non-color screens. Added ability to use alternative beep sound and background pattern (thanks Matthew for the pattern tip).
1.0.6 Just a little patch. Kalk now accepts both the dot and the comma as decimal separators. This is for European users that have a comma instead of a dot on the numeric keypad.
1.0.7 Corrected a little interface design flaw that prevented correct cut/copy/paste of numbers with exponents. As a side effect, entry of numbers with exponents is now easier. The sign of the exponent (like in 1.34e+23) was interpreted like an operator for addition. Now Kalk works as follows: if the last character in the current edit line is the "e", the next time you type a "+" (plus) or a "-" (minus) it will be interpreted like the sign for the exponent. In all other situations Kalk will behave normally. I think this is intuitive enough (it works better than it sounds here; run Kalk and see by yourself); the Option-minus alternative still works as before.
Furthermore, I make no warranty with respect to the quality of this software, nor do I warrant that its operation will be error-free. The software is provided “as is” and without warranty of any kind, express or implied. The author claims no liability for data loss or any other problems caused directly or indirectly by use of the “Kalk” application.
This software may be included in any disk or CD-ROM library of public domain and shareware software sold by a non-profit organization. This software may not be included in any commercial software collection sold for profit, nor may it be bundled with any commercial software, hardware, books, or other media without the prior written consent of the author.
