@Thomas Klemm -> CORDIC Article

[pito]

WP34s calc and various other arbitrary precision decimal fp libs/wrappers are using the IBM's decNumber library (which sets the standards). There are some settings for the rounding inside (context something), I never messed with them in detail, though. Maybe the difference between the results is related to the proper rounding setting's "know-how" with the library..

mpdecimal for example:

Quote:libmpdec - C/C++ library
libmpdec is a complete implementation of the General Decimal Arithmetic Specification. The specification, written by Mike Cowlishaw from IBM, defines a general purpose arbitrary precision data type together with rigorously specified functions and rounding behavior. As described in the scope section of the specification, libmpdec will - with minor restrictions - also conform to the IEEE 754-2008 Standard for Floating-Point Arithmetic, provided that the appropriate context parameters are set...