SIMPLE_GA
A Simple Genetic Algorithm

SIMPLE_GA is a C++ program which implements a simple genetic algorithm, by Dennis Cormier and Sita Raghavan.

Here, we consider the task of constrained optimization of a scalar function. That is, we have a function F(X), where X is an M-vector satisfying simple constraints for each component I:

        X_MIN[I] <= X[I] <= X_MAX[I]

and, subject to those constraints, we seek a vector X which maximizes the value F(X).

In the example given here, the spatial dimension M is 3, the function F(X) is X[1]^2 - X[1]*X[2] + X[3], and the constraints are

        0 <= X[1] <= 5
        0 <= X[2] <= 5
       -2 <= X[3] <= 2

The correct solution is [5,0,2].

Licensing:

The computer code and data files made available on this web page are distributed under the GNU LGPL license.

Languages:

SIMPLE_GA is available in a C++ version.

Related Programs and Data:

IMAGE_MATCH_GENETIC, a MATLAB program which tries to match a 256x256 JPEG image by blending 32 colored rectangles, using ideas from genetic algorithms, based on an example by Nick Berry.

Author:

Original version by Dennis Cormier, Sita Raghavan. This C++ version by John Burkardt.

Reference:

Zbigniew Michalewicz,
Genetic Algorithms + Data Structures = Evolution Programs,
Third Edition,
Springer, 1996,
ISBN: 3-540-60676-9,
LC: QA76.618.M53.

Source Code:

simple_ga.cpp, the source code.

Examples and Tests:

simple_ga_input.txt, an input file.
simple_ga_output.txt, the output file.

List of Routines:

MAIN supervises the genetic algorithm.
CROSSOVER selects two parents for the single point crossover.
ELITIST stores the best member of the previous generation.
EVALUATE implements the user-defined valuation function
I4_UNIFORM_AB returns a scaled pseudorandom I4 between A and B.
INITIALIZE initializes the genes within the variables bounds.
KEEP_THE_BEST keeps track of the best member of the population.
MUTATE performs a random uniform mutation.
R8_UNIFORM_AB returns a scaled pseudorandom R8.
REPORT reports progress of the simulation.
SELECTOR is the selection function.
TIMESTAMP prints the current YMDHMS date as a time stamp.
XOVER performs crossover of the two selected parents.

You can go up one level to the C++ source codes.

Last revised on 28 April 2014.

SIMPLE_GA A Simple Genetic Algorithm