ga-php

Genetic algorithm implemented based on this tutorial

How to build

git clone https://github.com/mad654/ga-php.git
cd ga-php
make

How to run

make run

# or

bin/app gen-algo:tutorial

How it works and what it does

Implements this tutorial See src/GenAlgo/SimpleAlgorithm.php for details.

Required parameters

They are defined with the following defaults:

TARGET_NUMBER = 42
TEST_COUNT = 10

Which means on call of this command would try to find 10 solutions for number 42.

If you want to change the test count or the target number you can change etc/config or use system environment variables:

TARGET_NUMBER=99 TEST_COUNT=100 bin/app gen-algo:tutorial

Play with evolution parameters

You want to evaluate how which parameter influences the performance of the algorithm?

Adjust the setting in etc/config :

MAX_POPULATIONS=100
POPULATION_SIZE=100
CROSSOVER_RATE=0.7
MUTATION_RATE=0.001
MAX_SELECTION_ATTEMPTS=10000

or simply use system environment variables:

MAX_POPULATIONS=100 \
POPULATION_SIZE=100 \
CROSSOVER_RATE=0.7 \
MUTATION_RATE=0.001 \
MAX_SELECTION_ATTEMPTS=10000 \
bin/app gen-algo:tutorial

Events

Currently this events are fired and handled for logging purposes, to give you a idea whats going on.

Results

You can watch which results were calculated by

tail -f var/log/genalgo.result-*.json

AlgorithmTestRunner events

This 4 events represent the current state of test runner.

• RunStartedEvent
• SingleTestStarted
• SingleTestFinished
• RunFinishedEvent

tail -f var/log/genalgo.debug-*.json | grep GENALGO.DEFAULT.TUTORIAL.INFO

Algorithm events

This events represent the current internal state of the algorithm. So if you wan't to take a deeper look, this will be you friend:

tail -f var/log/genalgo.debug-*.json | grep GENALGO.DEFAULT.TUTORIAL.DEBUG

• NewOutcomeCreated
• PopulationCreated
• SpezSelected
• PairSelected
• PopulationFitnessCalculated

results via rsyslog server logging

If you want to compute results in a multi process / multi host environment you should enable logging to rsyslog server in order to make sure all things logged well.

For now we added support for logging results to rsyslogd.

You can enable APP_LOG_RSYSLOG=true in etc/config and results are send via UDP to the specified rsyslog server. See APP_LOG_HOST and APP_LOG_PORT port to.

setup rsyslog server

allow remote logs reception

Debian jessie

Add a new rsyslog config:

cat > /etc/rsyslog.d/20-gen-algo.conf

with the following content

$template json,"%msg%,\n"
$template GaFile, "/var/log/gen-algo/%$YEAR%/%$MONTH%/%$DAY%/%HOSTNAME%/%$YEAR%%$MONTH%%$DAY%T_%HOSTNAME%.gen-algo.json"

$RuleSet remote

*.* -?GaFile;json

# switch back to the default ruleset:
$RuleSet RSYSLOG_DefaultRuleset

# Bind the remote messages to the ruleset remote.
# NOTE: the server must be started after the BindRuleset
$ModLoad imudp
$InputUDPServerBindRuleset remote
$UDPServerRun 514

2. Configure logging behavior

• Only log to one file
• Only log json stuff
• Rotate daily or by 100 MB
• max 100 files, min 3 days
• Add date to filename something like this /var/log/gen-algo/2016/09/23/hostname/20160923T120001_hostname.gen-algo.json for easy rsync to archive

ROADMAP

• [DONE] integrate as command
• [DONE] add configuration object feature/mad654/configuration
• [DONE] make file fetches own local composer to bin/composer
• [DONE] emmit events [start, ok, error] feature/mad654/emit-events
• make fitness function configurable