exs64: xorshift64star PRNG for Erlang

Note 12-JAN-2016: this algorithm is no longer listed as a part of Xorshift*/+ webpage. See https://web.archive.org/web/20150905215225/http://xorshift.di.unimi.it/ for the old archive. No further development will be made. Use exsplus or the rand module in OTP 18 and later.

xorshift64star is a 64-bit PRNG of (2^64-1) period.

See http://xorshift.di.unimi.it/ for the further details.

LICENSE

MIT License.

(The code under c-example directory is licensed CC0/public domain.)

Tested platforms

• FreeBSD/amd64 10.1-STABLE with Erlang/OTP 17.4 and HiPE

• OS X x86_64 10.10.1 with Erlang/OTP 17.4 and HiPE

• HiPE is not a requirement but recommended to be enabled.

A preliminary test shows the exs64 functions takes less execution time than twice of random module on a x86_64 or amd64 architecture environment, and roughly the same speed as the exsplus (xorshift128plus) functions.

Make options (of erlang.mk)

• Makefile works on both BSD/GNU make
• Makefile.[module_name] is the real GNU make file; edit this file for modification
• Building: make
• Documentation: make docs
• Testing: make tests
• Execution speed benchmark: make speed
• See also erlang.mk for the details

TODO

• More seeding algorithms
• More evaluation and refactoring

Authors

Algorithm by Sebastiano Vigna, and he made it public domain.

Programmed by Kenji Rikitake.

Contributors

Dan Gudmundsson