The GA Procedure

Mutate Call

  • call Mutate ( selected, seg, type<, parameter1, parameter2, …> );

The Mutate call executes a genetic mutation operator from within a user subroutine. The inputs to the subroutine are as follows:

selected  

is an array that specifies the solution to be mutated.

seg

is the desired segment of the solution to which the mutation should be applied.

type

is the type of mutation operator to apply, which also determines the number and type of parameters expected.

parameter1-n

are optional parameters applicable to some operators.

The accepted values for type and the corresponding parameters are summarized in Table 4.2.

Table 4.2: Mutation Operator Types

Type

Encodings

Parameters

'delta'

real, integer

delta

   

n

'invert'

sequence

 

'swap'

sequence

n

'uniform'

real, integer, Boolean

np


The parameters are as follows:

delta  

is a vector of delta values for each component of the solution, used only for the Delta mutation operator.

n

specifies the number of solution elements that should be mutated for the Delta operator, and the number of swaps that should be made for the Swap operator.

np

specifies the number of solution elements that should be mutated, if np is integer; specifies the mutation probability for each solution element if $0 < np < 1$.

The Mutate call should be made only from within a user mutation subroutine. The precise action of these mutation operators is described in the section Mutation Operators.