Documentation of seltour

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Function Synopsis

NewChromIx = seltour(FitnV, Nsel, Dummy);

Help text

 SELection by TOURnament

 This function performs SELection by TOURnament.

 Syntax:  NewChrIx = seltour(FitnV, Nsel)

 Input parameters:
    FitnV     - Column vector containing the fitness values of the
                individuals in the population.
    Nsel      - Number of individuals to be selected

 Output parameters:
    NewChromIx- Column vector containing the indexes of the selected
                individuals relative to the original population, shuffeld.
                The new population, ready for mating, can be obtained
                by calculating OldChrom(NewChromIx,:).

 The tournament size Tour is determined from the highest
 fitness value ceil(max(FitnV)). If ranking was used, this
 means ceil(SP);
    FitnV = [1.0; 1.1; 1.9;  0.5; 1.3]; ==> Tour = 2;
    FitnV = [1.6; 2.1; 3.05; 1.0; 0.4]; ==> Tour = 4;
 The tournament size should be in [1, Nind]. If not, Tour is set
 to one of these values and a message is displayed.
 For Tour==1 tournament selection is identical to random selection
 (no selective pressure). 

 See also: selection, selsus, selrws, seltrunc, sellocal

 Example:
    % define fitness vector
       FitnV = [.1; .9; 1.6; 2.0; 0.4; 1.3; 1.7; 0.7; 0.2];
    % selects 6 indices from FitnV, Tour = 2;
       NewChromIx = seltour(FitnV, 6);
    % possible result
       NewChromIx = [4; 7; 6; 7; 6; 5];
    % Get selected individuals from population Chrom
       SelChrom = Chrom(NewChromIx, :)

Cross-Reference Information