Documentation of mutcomb

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Function Synopsis

NewChrom = mutcomb(Chrom, VLUB, MutOpt, MutType)

Help text

 MUTation for combinatorial problems

 This function takes the individuals of the current
 population, mutates each indivdual with given probability 
 and returns the resulting population.
 Mutation can be done by:
  - swapping 2 variables of the individual
  - moving 1 variable from one position to another (insertion)
  - inverting all positions between two positions
 The additional input variable MutType defines this.

 If mutation is 1/Nvar or larger, every individual is mutated ones.
 If mutation rate is > 1/Nvar, additional mutations (swap or 
 insertion or invertion of variables) are performed. That means, 
 for some individuals more than one mutation of variables takes 
 place. A mutation rate of 2/Nvar produces (statistically) 
 2 mutations of variables per individual.
 The mutation range and precision are used for all mutations.

 This mutation operator may be used with every variable 
 representation, as long as the swap of the variables makes any sense.
 The mutation operator just exchanges/swaps the variables, no change 
 of variable value is performed.

 Syntax:  NewChrom = mutcomb(Chrom, VLUB, MutOpt, MutType)

 Input parameters:
    Chrom     - A matrix containing the chromosomes of the
                current population. Each row corresponds to
                an individuals string representation.
    VLUB      - Matrix containing the boundaries of each variable.
                not used here, necessary for compatibility with
                real valued mutation
    MutOpt    - (optional) Vector containing mutation options
                MutOpt(1): MutRate - number containing the mutation rate -
                           probability for mutation of a variable
                           if omitted or NaN, MutRate = 1/variables per
                           individual is assumed
                MutOpt(2): MutRange - (optional) number for shrinking the
                           mutation range in the range [0 1], possibility to
                           shrink the range of the mutation depending on,
                           for instance actual generation.
                           if omitted or NaN, MutRange = .2 is assumed
                MutOpt(3): MutPreci - (optional) precision of mutation steps
                           if omitted or NaN, MutPreci = 8 is assumed
   MutType    - (optional) Scalar indicating type of combinatorial mutation
                  0: swap
                  1: insertion / move
                  2: inversion

 Output parameter:
    NewChrom  - Matrix containing a mutated version of Chrom.

 See also: mutate, mutswap, mutinvert, mutinsert, mutswaptyp, mutreal, mutbin, mutint, initip

Cross-Reference Information

This function is called by
GEATbx: Main page  Tutorial  Algorithms  M-functions  Parameter/Options  Example functions 

This document is part of version 3.8 of the GEATbx: Genetic and Evolutionary Algorithm Toolbox for use with Matlab -
The Genetic and Evolutionary Algorithm Toolbox is not public domain.
© 1994-2006 Hartmut Pohlheim, All Rights Reserved, (