Documentation of initip

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Function Synopsis

Chrom = initip(Nind, VLUB);

Help text

 CReaTe an initial (Integer value) Population

 This function creates a population of given size of random integer value.

 It is ensured, that the values are created uniform at random, even at the 
 bounds of the initialization range.
 What is the problem? 
 Try hist(initip(10000, [1; 10])), look for the first and last area.
 Then try hist(initip(10000, [0.5001; 10.4999])) for a solution.
 Thus, the upper and lower boundary is extended, to give the bounded
 integers also a uniform initialization range of (nearly) 1.

 Syntax:  Chrom = initip(Nind, FieldDR);

 Input parameters:
    Nind      - A scalar containing the number of individuals in the new population.
    VLUB      - A matrix of size 2 by number of variables describing the boundaries 
                of each variable. The bounds should be integers, to get an even 
                distribution of the values.
                For more info, see initrp.

 Output parameter:
    Chrom     - A matrix containing the random valued individuals of the
                new population of size Nind by number of variables.

 See also: initrp, initbp

Cross-Reference Information

Listing of function initip

% Author:   Hartmut Pohlheim
% History:  17.10.1997  file created
%           13.03.2005  bounds are extended by (nearly) 0.5 for uniform initialization
%                       at the defined bounds


function Chrom = initip(Nind, VLUB);

% Create initial population

   % First, extend the bound array
   ValExtend = 0.4999;
   VLUBIntern = VLUB + repmat([-ValExtend; ValExtend], [1, size(VLUB,2)]);
   
   % Create real population and round the values
   Chrom = round(initrp(Nind, VLUBIntern));


% End of function