other algorithms use factor-2s, put it back to normal

db4
Doug Coleman 2008-01-13 07:51:46 -10:00
parent 37cde9e234
commit 0613d01fcc
1 changed files with 11 additions and 4 deletions

View File

@ -20,12 +20,19 @@ SYMBOL: trials
: random-bits ( m -- n ) 2^ random ; foldable
: factor-2s ( zero n -- r s )
#! factor an even number into 2 ^ s * m
dup even? [ -1 shift >r 1+ r> factor-2s ] when ;
TUPLE: positive-even-expected n ;
: (factor-2s) ( r s -- r s )
dup even? [ -1 shift >r 1+ r> (factor-2s) ] when ;
: factor-2s ( n -- r s )
#! factor an even number into s * 2 ^ r
dup even? over 0 > and [
positive-even-expected construct-boa throw
] unless 0 swap (factor-2s) ;
:: (miller-rabin) | n prime?! |
0 n 1- factor-2s s set r set
n 1- factor-2s s set r set
trials get [
n 1- [1,b] random a set
a get s get n ^mod 1 = [