AriCalculator is a home made pocket calculator.

[Paul Dale]

(06-15-2017 04:52 AM)Dan Wrote:  Clive Maxfield wrote a great book on algorithms for the four basic functions ("How computers do math"), but it only deals with integers and I couldn't find anything that looks at floating-point numbers in similar detail.

There are quite a few things floating around the internet and in print. The last message on the first page of this thread lists some of the books I've found useful. The link to Kahan's site is invaluable for background. Also add in Knuth's Seminumerical Algorithms.

The WP 34S codebase implements a lot of decimal floating point functions. Other places to look are the source code for the GNU C library, the R statistics package, GNU's bc, the Cephes library -- these are all binary floating point based. The Intel decimal library is good but the algorithms aren't suitable for small processors (table based / using binary floating point functions as estimates).

CASIO's Keisan online calculator is good for checking results as is Wolfram's Alpha (by default it limits floating point accuracy which has caught me out).


- Pauli