Migration – the migration schemes, distributed GA

This module contains all the migration schemes and the distributed GA related functions.

New in version 0.6: The Migration module.

class Migration.MigrationScheme(host, port, group_name)

This is the base class for all migration schemes

Parameters:

• host – the source hostname
• port – the source host port
• group_name – the group name

exchange()

Exchange individuals

getCompressionLevel()

Get the zlib compression level of network data

The values are in the interval described on the Network.pickleAndCompress()

getGroupName()

Gets the group name

Note

all islands of evolution which are supposed to exchange individuals, must have the same group name.

getMigrationRate()

Return the the generation frequency supposed to migrate and receive individuals

Return type:the number of generations

getNumIndividuals()

Return the number of individuals that will migrate

Return type:the number of individuals to be replaced

getNumReplacement()

Return the number of individuals that will be replaced in the migration process

isReady()

Returns true if is time to migrate

select()

Pickes an individual from population using specific selection method

Return type:an individual object

selectPool(num_individuals)

Select num_individuals number of individuals and return a pool

Parameter:num_individuals – the number of individuals to select Return type:list with individuals

selector

This is the function slot for the selection method if you want to change the default selector, you must do this:

migration_scheme.selector.set(Selectors.GRouletteWheel) 

setCompressionLevel(level)

Set the zlib compression level of network data

The values are in the interval described on the Network.pickleAndCompress()

Parameter:level – the zlib compression level

setGAEngine(ga_engine)

Sets the GA Engine handler

setGroupName(name)

Sets the group name

Parameter:name – the group name

Note

all islands of evolution which are supposed to exchange individuals, must have the same group name.

setMigrationRate(generations)

Sets the generation frequency supposed to migrate and receive individuals.

Parameter:generations – the number of generations

setMyself(host, port)

Which interface you will use to send/receive data

Parameters:

• host – your hostname
• port – your port

setNumIndividuals(num_individuals)

Set the number of individuals that will migrate

Parameter:num_individuals – the number of individuals

setNumReplacement(num_individuals)

Return the number of individuals that will be replaced in the migration process

Parameter:num_individuals – the number of individuals to be replaced

start()

Initializes the migration scheme

stop()

Stops the migration engine

class Migration.WANMigration(host, port, group_name)

This is the Simple Migration class for distributed GA

Example:

>>> mig = WANMigration("192.168.0.1", "10000", "group1")

Parameters:

• host – the source hostname
• port – the source port number
• group_name – the group name

exchange()

This is the main method, is where the individuals are exchanged

getCompressionLevel()

Get the zlib compression level of network data

The values are in the interval described on the Network.pickleAndCompress()

getGroupName()

Gets the group name

Note

all islands of evolution which are supposed to exchange individuals, must have the same group name.

getMigrationRate()

Return the the generation frequency supposed to migrate and receive individuals

Return type:the number of generations

getNumIndividuals()

Return the number of individuals that will migrate

Return type:the number of individuals to be replaced

getNumReplacement()

Return the number of individuals that will be replaced in the migration process

isReady()

Returns true if is time to migrate

select()

Pickes an individual from population using specific selection method

Return type:an individual object

selectPool(num_individuals)

Select num_individuals number of individuals and return a pool

Parameter:num_individuals – the number of individuals to select Return type:list with individuals

selector

This is the function slot for the selection method if you want to change the default selector, you must do this:

migration_scheme.selector.set(Selectors.GRouletteWheel) 

setCompressionLevel(level)

Set the zlib compression level of network data

The values are in the interval described on the Network.pickleAndCompress()

Parameter:level – the zlib compression level

setGAEngine(ga_engine)

Sets the GA Engine handler

setGroupName(name)

Sets the group name

Parameter:name – the group name

Note

all islands of evolution which are supposed to exchange individuals, must have the same group name.

setMigrationRate(generations)

Sets the generation frequency supposed to migrate and receive individuals.

Parameter:generations – the number of generations

setMyself(host, port)

Which interface you will use to send/receive data

Parameters:

• host – your hostname
• port – your port

setNumIndividuals(num_individuals)

Set the number of individuals that will migrate

Parameter:num_individuals – the number of individuals

setNumReplacement(num_individuals)

Return the number of individuals that will be replaced in the migration process

Parameter:num_individuals – the number of individuals to be replaced

setTopology(graph)

Sets the topology of the migrations

Parameter:graph – the Util.Graph instance

start()

Start capture of packets and initialize the migration scheme

stop()

Stops the migration engine