| Rfractran-package {Rfractran} | R Documentation |
A 'FRACTRAN' Interpreter and Some Helper Functions
Description
'FRACTRAN' is an obscure yet tantalizing programming language invented by John Conway of 'Game of Life' fame. The code consists of a sequence of fractions. The rules are simple. First, select an integer to initialize the process. Second, multiply the integer by the first fraction. If an integer results, start again with the new integer. If not, try the next fraction. Finally, if no such multiplication yields an integer, terminate the program. For more information, see <https://en.wikipedia.org/wiki/FRACTRAN> .
Details
The DESCRIPTION file:
| Package: | Rfractran |
| Type: | Package |
| Title: | A 'FRACTRAN' Interpreter and Some Helper Functions |
| Version: | 1.0.1 |
| Date: | 2023-08-28 |
| Authors@R: | c(person(given = "Carl", family = "Witthoft", role = c("aut","cre"), email= "cellocgw@gmail.com")) |
| Depends: | gmp |
| Description: | 'FRACTRAN' is an obscure yet tantalizing programming language invented by John Conway of 'Game of Life' fame. The code consists of a sequence of fractions. The rules are simple. First, select an integer to initialize the process. Second, multiply the integer by the first fraction. If an integer results, start again with the new integer. If not, try the next fraction. Finally, if no such multiplication yields an integer, terminate the program. For more information, see <https://en.wikipedia.org/wiki/FRACTRAN> . |
| License: | LGPL-3 |
| Author: | Carl Witthoft [aut, cre] |
| Maintainer: | Carl Witthoft <cellocgw@gmail.com> |
FRACTRAN is an obscure yet tantalizing programming "language" invented by John Conway of "Game of Life" fame. The code consists of a sequence of fractions. The operation is simple. 1 - Initalize with an integer 2 - Multiply the integer by the first fraction. If an integer results, start again with the new integer. If not, try the next fraction. 3 - If no such multiplication yields an integer, terminate the program. One warning: there is a FRACTRAN program that can be found on the web which is supposed to generate the digits of pi. Unfortunately, it's known to have a bug which causes it not to work. So far nobody has found a correction for it.
Author(s)
NA Maintainer: NA
References
https://esolangs.org/wiki/Fractran https://oeis.org/wiki/List_of_FRACTRAN_programs_to_compute_core_sequences
Examples
##Not Run
# addition: { 3/2 } . Enter 2^a*3^b and get 3^(a+b) answer when terminated
# multiplication:
# { 455/33, 11/13, 1/11, 3/7, 11/2, 1/3 }
# then enter 2^a*3^b Terminates with 5^(a*b)
# prime generator (This function never terminates.)
#start with 10, feed to [7/3 99/98 13/49 39/35 36/91 10/143 49/13 7/11 1/2 91/1]
# and whenever the result of a run is of the form 10^p , p is prime