An Arbitrary Precision Calculator and Base Converter.


Operating notes -- 12 April 2013


1)  Download the program from here:  OttletCalc  It only works on Windows OS.


2)  There is no installation.  Move the OttletCalc.exe file from the zip file you downloaded to a convenient directory.  Double click on it to run, or make a shortcut to it.  It does its file i/o to the default directory, which most likely will be the same directory you put it in.


3)  The program runs in a Command Prompt window.  I highly recommend the following properties changes of the command prompt:  Click on the icon in the extreme upper left hand corner of the window.  Select “Properties”.  Go to the “Options” tab.  Make sure there is a checkmark next to “QuickEdit Mode”.  Go to the “Layout” tab.  Change the Width of both the Screen Buffer and the Window Size to 120 characters (if that still fits on your monitor).  I also make the Screen Buffer Height at least 1000.


4) Once you have selected “QuickEdit Mode” you can copy and paste in the command prompt window by using <left click> <right click> to select and copy and by using <right click> to paste.  <ctrl> c and <ctrl> v do not work!  Note that you cannot paste more than about 4000 characters into the window, so entering a really large number requires reading it from a file.


5) Be sure to set enough digits using the –d command before you start.  More accuracy will (probably) not magically appear on existing numbers when you increase the number of digits with –d.


6)  The character set for bases is 0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz


7) For input, with bases of 36 or less, you can use upper or lower case interchangeably.


8) Since commands start with lower case letters, if your number starts with a lower case letter you will have to put a 0 (zero) in front of it.  In the case of negative numbers, if the first digit is any letter, you will have to put a 0 between the - and the letter.


9) When inputting numbers into the command prompt window, there can be no white space or commas in the number.  When inputting numbers from a file, all white space is ignored, so there can be things like line feeds in the middle of the number.  Be sure there is only one number and nothing else printable in the file.


10) The calculator uses RPN and a 96 level stack for calculations.  RPN means that when you type a number, it goes into the bottom of the stack.  Operators like “+” will add the bottom two levels of the stack, remove them, and place the result in the bottom of the stack.  If you pine for algebraic notation with parentheses, consider how poorly that works with gigantic numbers.


11) The limit on the number of digits you can use is set by the MAPM library the program is built on.  The limit is poorly documented but is larger than the amount of memory a 32-bit application can use, so the program will crash due to running out of memory if you ask for more than about one billion digits.


12) In base 10, you can use scientific notation like “2.3E+123456”.  The limit on the exponent size appears to be +/- 2^31 - 1.  That’s 10^ 2147483647.  If you overflow that, it will stupidly wrap around to a negative exponent.  In bases other than 10, you can’t use scientific notation.


OttletCalc Revision History:

Version 0.0 – Initial release

Version 0.1 – fix problem reading really big numbers in bases other than 10