Rubicite Genetic Algorith Framework Tutorial
General:
Basic Info
Selection Bias
Hard Problem
Downloads
Crossovers:
Cycle
Order X
Order 1
Edge Recombination
PMX Crossover
Order Multiple
Direct Insertion
Mutations:
Inversion
Random Slide
Insertion
Single Swap
Random Swap
Scramble
Mutation Technique:
Random Swap Mutation
The Random Swap Mutation is similar to
single swap
, but swaps a random string of consecutive values instead of a single value.
VB.NET 2008 Source Code
' This is like single swap, but swaps a random string of consecutive values instead ' Doubles(0) = Minimum Swap Size [0, 0.33] ' Doubles(1) = Maximum Swap Size [0, 0.33] 'This will generate the Y value for the ChildMutationWithRandomSizedSwaps function Public Function RSS_GetY(ByRef randswapsize As Integer, ByVal XPos As Integer) Dim done As Boolean = False 'Need to determine the start, end, and width of the invalid area. 'Special case: when X is between 0 and randomswapsize - 1 'Start and End of invalid area variables refer to indexes Dim StartofInvalidArea, WidthofInvalidArea As Integer Dim LeftNumberofValid, RightNumberofValid, EndofInvalidArea As Integer StartofInvalidArea = XPos - randswapsize + 1 If (StartofInvalidArea < 0) Then 'If start pos of invalid area < 0 then it corrects itself + corrects width of invalid area Dim temp22 As Integer = StartofInvalidArea * -1 StartofInvalidArea = 0 WidthofInvalidArea = (randswapsize + randswapsize - 1) - temp22 Else WidthofInvalidArea = randswapsize + randswapsize - 1 End If EndofInvalidArea = StartofInvalidArea + WidthofInvalidArea - 1 'Determine the quantity of valid spots for Y to the left and right of the invalid area ' LeftNumberofValid refers to quantity of valid values left of the invalid area ' Rightnumberofvalid refrs to quantity of valid values right of the invalid area LeftNumberofValid = StartofInvalidArea RightNumberofValid = (AlleleCount - randswapsize) - LeftNumberofValid - WidthofInvalidArea + 1 If (LeftNumberofValid < 0) Then 'if left number of valid less than zero then set to 0 LeftNumberofValid = 0 End If If (RightNumberofValid < 0) Then 'if right number of valid less than zero then set to 0 RightNumberofValid = 0 End If 'Y can either be on the left of the invalid area or the right ' Depending on the random number generated, Y will end up on either side Dim StartYPos As Integer = RAND.Next(0, (LeftNumberofValid + RightNumberofValid - 1)) If (StartYPos < LeftNumberofValid) Then Return StartYPos Else StartYPos = EndofInvalidArea + (StartYPos - LeftNumberofValid) + 1 Return StartYPos End If End Function Public Sub RandomSwap_Mutation(ByRef Child1 As PChromo) Dim K As Integer 'X refers to the starting index of the first swap area 'Y refers to the starting index of the second swap area 'These areas are "randomwapsize" long Dim randswapsize = RAND.Next(RandomSwap_Master.Doubles(0) * AlleleCount, RandomSwap_Master.Doubles(1) * AlleleCount) 'Doubles(0) = min swap size || Doubles(1) = max swap size Dim X As Integer = RAND.Next(0, AlleleCount - randswapsize) Dim Y As Integer = RSS_GetY(randswapsize, X) 'Calls purpose built function for determining Y value 'Swap the Values For counter As Integer = 0 To (randswapsize - 1) K = Child1.Alleles(X + counter) Child1.Alleles(X + counter) = Child1.Alleles(Y + counter) Child1.Alleles(Y + counter) = K Next End Sub
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