single_point_crossover

Single point crossover operator.

x_i_new, of_i_new, fit_i_new, neof, report = single_point_crossover(of_function, parent_0, parent_1, n_dimensions, x_upper, x_lower, none_variable=None)

Input variables

Name	Description	Type
of_function	Is the objective function that will be used to evaluate the result of the crossover	Py function (def)
parent_0	Represents the first parent for the crossover	List
parent_1	Represents the second parent for the crossover	List
n_dimensions	number of dimensions	Integer
x_upper	Upper limit of the design variables.	List
x_lower	Lower limit of the design variables.	List
none_variable	None variable. Default is None. Use in objective function	None, List, Float, Dictionary, String or any

Output variables

Name	Description	Type
x_i_new	Update variables of the i agent.	List
of_i_new	Update objective function value of the i agent.	Float
fit_i_new	Update fitness value of the i agent.	Float
neof	Number of evaluations of the objective function.	Integer
report_move	Report about the male moviment process.	String

Example 1

# Import
from metapy_toolbox import single_point_crossover

# Data
father1 = [3.7, 3.9, 1.8, 3.7, 3.1]
father2 = [1.3, 4.9, 1.7, 3.9, 3.4]
nDimensions = len(father1)
xUpper = [5, 5, 5, 5, 5]
xLower = [1, 1, 1, 1, 1]
noneVariable = None

# Objective function
def objFunction(x, _):
    """Example objective function"""
    x0 = x[0]
    x1 = x[1]
    of = x0 ** 2 + x1 ** 2
    return of

# Call function
xNew, ofNew, fitNew, neof, report = single_point_crossover(objFunction, father1, father2, nDimensions, xUpper, xLower, noneVariable)

# Output details
print('x new ', xNew)
print('of new ', ofNew)
print('fit new', fitNew)
print('number of evalutions objective function', neof)

x new  [1.3, 3.9, 1.8, 3.7, 3.1]
of new  16.9
fit new 0.0558659217877095
number of evalutions objective function 2

To check the movement report just apply the following instruction.

# Report details
arq = "report_example.txt"

# Writing report
with open(arq, "w") as file:
    file.write(report)

Open report_example.txt.

    Crossover operator - Single point
    current p0 = [3.7, 3.9, 1.8, 3.7, 3.1]
    current p1 = [1.3, 4.9, 1.7, 3.9, 3.4]
    cut position 1
    cut parent_0 -> of_a [3.7]
    cut parent_1 -> of_a [4.9, 1.7, 3.9, 3.4]
    cut parent_1 -> of_b [1.3]
    cut parent_0 -> of_b [3.9, 1.8, 3.7, 3.1]
    offspring a = [3.7, 4.9, 1.7, 3.9, 3.4], of_a = 37.7
    offspring b = [1.3, 3.9, 1.8, 3.7, 3.1], of_b = 16.9
    update n_dimensions = [1.3, 3.9, 1.8, 3.7, 3.1], of = 16.9, fit = 0.0558659217877095