This is a slightly modified version of the constructive reals calculator developed by Hans-J. Boehm at SGI. The copyright belongs to SGI. Since it appears to no longer be available on the SGI site, it was rehosted here, as allowed by its license.
Your browser does not support JavaScript, or it has been disabled. Hence we cannot determine the identity of the browser. You will need a browser with support for at least Java 1.1 to correctly run the calculator Applet. Netscape 4 or Internet Explorer version 4 or later should suffice. To try to run the applet anyway, click here.
The calculator uses reverse Polish notation. To add 1 and 2, either click <1><enter><2><+> on the calculator keypad, or click on the display, so that it receives keyboard input, and type 1<space>2+ on the keyboard. For more detailed instructions, click here.
To demonstrate the effect of demand-driven evaluation, try
123 <+/-> <exp> <pi> <+> <ln> <exp> <pi> <-> <ln>.
or
10 <enter> 25 <^> <atan> <tan>
CR provides constructive reals as a subclass of Number. Its interface is described here.
UnaryCRFunction provides some limited operations on unary functions over the constructive reals. It also provides a large number of constants for commonly used functions. Its interface is described here.
Some general information on the implementation is here.
The entire calculator can be downloaded as a compressed tar file here.