iSharkFly-Docs
/
java-tutorials
1
0
Fork 0
Code Issues Pull Requests Packages Projects Releases Wiki Activity

Merge pull request #1336 from eugenp/ac_refactor 

ACO refactor
This commit is contained in:
maibin 2017-03-08 15:29:47 +01:00 committed by GitHub
parent a419237226 9758e2ce3c
commit 3de5b732a9
1 changed files with 10 additions and 28 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

38
core-java/src/main/java/com/baeldung/algorithms/ga/ant_colony/AntColonyOptimization.java
View File

@ -18,8 +18,8 @@ public class AntColonyOptimization {
private int maxIterations = 1000; private int maxIterations = 1000;
public int numberOfCities; private int numberOfCities;
public int numberOfAnts; private int numberOfAnts;
private double graph[][]; private double graph[][];
private double trails[][]; private double trails[][];
private List<Ant> ants = new ArrayList<>(); private List<Ant> ants = new ArrayList<>();
@ -28,8 +28,8 @@ public class AntColonyOptimization {
private int currentIndex; private int currentIndex;
public int[] bestTourOrder; private int[] bestTourOrder;
public double bestTourLength; private double bestTourLength;
public AntColonyOptimization(int noOfCities) { public AntColonyOptimization(int noOfCities) {
graph = generateRandomMatrix(noOfCities); graph = generateRandomMatrix(noOfCities);
@ -43,26 +43,17 @@ public class AntColonyOptimization {
/** /**
* Generate initial solution * Generate initial solution
*
* @param n
* @return
*/ */
public double[][] generateRandomMatrix(int n) { public double[][] generateRandomMatrix(int n) {
double[][] randomMatrix = new double[n][n]; double[][] randomMatrix = new double[n][n];
random.setSeed(System.currentTimeMillis()); IntStream.range(0, n)
IntStream.range(0, n).forEach(i -> { .forEach(i -> IntStream.range(0, n)
IntStream.range(0, n).forEach(j -> { .forEach(j -> randomMatrix[i][j] = Math.abs(random.nextInt(100) + 1)));
Integer r = random.nextInt(100) + 1;
randomMatrix[i][j] = Math.abs(r);
});
});
return randomMatrix; return randomMatrix;
} }
/** /**
* Perform ant optimization * Perform ant optimization
*
* @return
*/ */
public void startAntOptimization() { public void startAntOptimization() {
IntStream.rangeClosed(1, 3).forEach(i -> { IntStream.rangeClosed(1, 3).forEach(i -> {
@ -73,8 +64,6 @@ public class AntColonyOptimization {
/** /**
* Use this method to run the main logic * Use this method to run the main logic
*
* @return
*/ */
public int[] solve() { public int[] solve() {
setupAnts(); setupAnts();
@ -94,7 +83,7 @@ public class AntColonyOptimization {
*/ */
private void setupAnts() { private void setupAnts() {
IntStream.range(0, numberOfAnts).forEach(i -> { IntStream.range(0, numberOfAnts).forEach(i -> {
ants.stream().forEach(ant -> { ants.forEach(ant -> {
ant.clear(); ant.clear();
ant.visitCity(-1, random.nextInt(numberOfCities)); ant.visitCity(-1, random.nextInt(numberOfCities));
}); });
@ -107,23 +96,18 @@ public class AntColonyOptimization {
*/ */
private void moveAnts() { private void moveAnts() {
IntStream.range(currentIndex, numberOfCities - 1).forEach(i -> { IntStream.range(currentIndex, numberOfCities - 1).forEach(i -> {
ants.stream().forEach(ant -> { ants.forEach(ant -> ant.visitCity(currentIndex, selectNextCity(ant)));
ant.visitCity(currentIndex, selectNextCity(ant));
});
currentIndex++; currentIndex++;
}); });
} }
/** /**
* Select next city for each ant * Select next city for each ant
*
* @param ant
* @return
*/ */
private int selectNextCity(Ant ant) { private int selectNextCity(Ant ant) {
int t = random.nextInt(numberOfCities - currentIndex); int t = random.nextInt(numberOfCities - currentIndex);
if (random.nextDouble() < randomFactor) { if (random.nextDouble() < randomFactor) {
IntStream.range(0, numberOfCities).filter(i -> i == t && !ant.visited(i)).findFirst(); IntStream.range(0, numberOfCities).filter(i -> i == t && !ant.visited(i)).findFirst(); //TODO unused
} }
calculateProbabilities(ant); calculateProbabilities(ant);
double r = random.nextDouble(); double r = random.nextDouble();
@ -140,8 +124,6 @@ public class AntColonyOptimization {
/** /**
* Calculate the next city picks probabilites * Calculate the next city picks probabilites
*
* @param ant
*/ */
public void calculateProbabilities(Ant ant) { public void calculateProbabilities(Ant ant) {
int i = ant.trail[currentIndex]; int i = ant.trail[currentIndex];