Dear Colleague,

I have released version 2.2 of my C++ software package `doubledouble' which
implements doubled-double (approximately 30 decimal place) floating point
arithmetic on IEEE 754 floating-point hardware.

This version includes many improvements suggested by Stefan Bauberger, Roger
Schlafly, Wayne Hayes, Victor Shoup, Tony Dixon, and Alan Miller. These include
new functions, portability enhancements and improvements to many details.

This is a development of code formerly released as `Quad version 2.0'.  The
name Quad has been dropped as the code does NOT implement the IEEE quadruple
precision format.   The name `doubledouble' was chosen instead since it is
distinctive and reminds one that an unusual data type is being used, and it
describes the format of two adjacent doubles. 

The code may be downloaded from
http://www-epidem.plantsci.cam.ac.uk/~kbriggs/doubledouble.html

Except where otherwise indicated by comments in the code, this software is
covered by the GNU Public License, as described in the included COPYLEFT
notice.

Keith Briggs kmb28@cam.ac.uk
