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python-biopython  1.60
Bio.GA.Crossover.GeneralPoint Namespace Reference


class  GeneralPointCrossover
class  TwoCrossover
class  InterleaveCrossover

Detailed Description

Generalized N-Point Crossover.

For even values of N, perform N point crossover 
  (select N/2 points each in the two genomes, and alternate)
For odd values of N, perform symmetric N+1 point crossover
  (select N/2 points for both genomes)
N-Point introduction (my notation):
    genome 1:    A-----B-----C-----D-----E-----F-----G
    genome 2:    a=====b=====c=====d=====e=====f=====g
    2-point, symmetric (points=1):
 A-----B-----C- 1 -D-----E-----F-----G
 a=====b=====c= 2 =d=====e=====f=====g
    returns: (ABCdefg, abcDEFG)

    2-point, asymmetric (points=2):
 A-----B- 1 -C-----D-----E-----F-----G
 a=====b=====c=====d=====e= 2 =f=====g
    returns: (ABfg, abcdeCDEFG)

and for the drastic (n can be arbitrary to the length of the genome!):
    12-point, symmetric (points=11):
 A- 1 -B- 2 -C- 3 -D- 4 -E- 5 -F- 6 -G
 a= 7 =b= 8 =c= 9 =d= 10 e= 11 f= 12 g
    returns: (AbCdEfG, aBcDeFg)
    (note that points=12 will yield the same result, but 11
     may be somewhat faster)