High-Precision Software Directory

Update: 29 Apr 2015

This web site (see software package links below) contains the LBNL double-double precision, quad-double precision and arbitrary precision (also termed "multiprecision" or "multiple precision") software, which was written over a period of several years by David H. Bailey (LBNL), Yozo Hida (U.C. Berkeley), Xiaoye S. Li (LBNL), Brandon Thompson (formerly of U.C. Berkeley, now at Synopsis), Karthik Jeyabalan (formerly at LBNL, now at Cornell) and Alex Kaiser (LBNL, now at NYU). Here are links to some of the authors' websites:

• Bailey's website
• Li's website

• MPFUN2015 (*NEW* Fortran-90 arbitrary precision package)
  Unix-based systems (including Apple MAC OSX systems): DHB software site
  
  This is a new Fortran-based package that is 100% thread-safe, even at the language interface level, by means of data structures and algorithmic techniques that avoid the need for any "context" (i.e., read/write global variables) or, except for exceedingly high precision, any initialization step, yet still permit the working precision level to be changed within the application. The package employs advanced algorithms, including FFT-based arithmetic and quadratically convergent transcendentals, for optimal performance even at very high precision levels. It also incorporates design features that detect, and provide means to overcome, accuracy problems that are rooted in the usage of inexact double-precision constants and expressions. A full-featured Fortran-90 interface, supporting both multiprecision real and complex datatypes, is provided, so that most users need only to make minor changes (typically type statements and I/O) to existing double-precision code.
  
  NOTE: This software was written independently by Bailey. The link above is to Bailey's personal website. This software was not written with support from the Lawrence Berkeley National Laboratory, nor does the Laboratory assume any responsibility for its usage or maintenance.
  
  
• ARPREC (C++/Fortran-90 arbitrary precision package)
  Unix-based systems (including Apple Macintosh systems): arprec-2.2.17.tar.gz
  Before downloading or installing this software, please read BSD-LBNL-License.doc (which contains license information) and the README file.
  
  This package supports a flexible, arbitrarily high level of numeric precision -- the equivalent of hundreds or even thousands of decimal digits (up to approximately ten million digits if needed). Special routines are provided for extra-high precision (above 1000 digits). The entire library is written in C++. High-precision real, integer and complex datatypes are supported. Both C++ and Fortran-90 translation modules are also provided that permit one to convert an existing C++ or Fortran-90 program to use the library with only minor changes to the source code. In most cases only the type statements and (in the case of Fortran-90 programs) read/write statements need be changed. Six implementations of PSLQ (one-, two- and three-level, regular and multi-pair) are included, as well as three high-precision quadrature programs. New users are encouraged to use this package, rather than MPFUN90 or MPFUN77 (see below).
  
  This verion of the ARPREC package now includes "The Experimental Mathematician's Toolkit", which is available as the program "mathtool" in the subdirectory "toolkit". This is a complete interactive high-precision arithmetic computing environment. One enters expressions in a Mathematica-style syntax, and the operations are performed using the ARPREC package, with a level of precision that can be set from 100 to 1000 decimal digit accuracy. Variables and vector arrays can be defined and referenced. This program supports all basic arithmetic operations, common transcendental and combinatorial functions, multi-pair PSLQ (one-, two- or three-level versions), high-precision quadrature, i.e. numeric integration (Gaussian, error function or tanh-sinh), and summation of series.
  
  
• QD (C++/Fortran-90 double-double and quad-double package)
  Unix-based systems (including Apple Macintosh systems): qd-2.3.15.tar.gz
  Before downloading or installing this software, please read BSD-LBNL-License.doc (which contains license information) and the README file.
  
  This package supports both a double-double datatype (approx. 32 decimal digits) and a quad-double datatype (approx. 64 decimal digits). The computational library is written in C++. Both C++ and Fortran-90 high-level language interfaces are provided to permit one to use convert an existing C++ or Fortran-90 program to use the library with only minor changes to the source code. In most cases only a few type statements and (for Fortran-90 programs) read/write statements need to be changed. PSLQ and numerical quadrature programs are included.
  
  
• MPFUN90 (Fortran-90 arbitrary precision package)
  Unix-based systems (including Apple Macintosh systems): mpfun90.tar.gz (version date 2010-08-25)
  Before downloading or installing this software, please read BSD-LBNL-License.doc (which contains license information) and the README file.
  
  This package is similar to the ARPREC package, except that it is written exclusively in Fortran-90 (i.e., no C++). As with the ARPREC package, Fortran-90 translation modules are also provided that permit one to convert an existing Fortran-90 program to use the library with only minor changes to the source code. The MPFUN90 package was recently revamped and improved to be completely compatible, at the Fortran user level, with the ARPREC package. In other words, a high-level Fortran-90 user program that works with the MPFUN90 software should also work with the ARPREC package. For instance, the F90 quadrature and PSLQ programs mentioned above that are included with the ARPREC package also work with MPFUN90, and are included in the MPFUN90 package. In addition, the Experimental Mathematician's Toolkit now works with MPFUN package as well.
  
  NOTE: This software is now quite old. The newer packages MPFUN2015 and ARPREC (see above) are recommended instead.