jenetics

Creating random seeds

Franz Wilhelmstötter, 2015.01.25

While implementing the Jenetics library, I faced the problem of creating seed values for the Random engines I used. The usual way for doing this, is to take the current time stamp.

public static long seed() {
    return System.nanoTime();
}

jenetics

Keybase proof

I hereby claim:

• I am jenetics on github.
• I am fwilhelm (https://keybase.io/fwilhelm) on keybase.
• I have a public key whose fingerprint is 3C2E EC52 F948 23B8 113A 527C BE5E C76F 7C08 4F3B

To claim this, I am signing this object:

jenetics

import static java.lang.Math.PI;
import static org.jenetics.engine.EvolutionResult.toBestPhenotype;

import java.util.Set;
import java.util.function.Predicate;
import java.util.stream.Collectors;

import org.jenetics.DoubleGene;
import org.jenetics.Genotype;
import org.jenetics.Phenotype;

jenetics

class WeaselSelector<
	G extends Gene<?, G>,
	C extends Comparable<? super C>
>
	implements Selector<G, C>
{
	@Override
	public Population<G, C> select(
		final Population<G, C> population,
		final int count,

jenetics

import static java.lang.Math.pow;
import static org.jenetics.internal.math.random.indexes;

import java.util.ArrayList;
import java.util.List;
import java.util.Random;
import java.util.stream.IntStream;

import org.jenetics.internal.util.IntRef;

jenetics

import static java.nio.file.Files.exists;

import java.io.IOException;
import java.nio.file.Files;
import java.nio.file.Path;
import java.nio.file.Paths;
import java.util.concurrent.CompletableFuture;
import java.util.concurrent.ExecutionException;
import java.util.concurrent.atomic.AtomicBoolean;

jenetics

import static java.lang.String.format;
import static java.lang.System.getProperty;
import static java.util.Objects.requireNonNull;
import static io.jenetics.engine.EvolutionResult.toBestPhenotype;
import static io.jenetics.jpx.Length.Unit.METER;

import java.io.IOException;
import java.io.InputStream;
import java.util.AbstractMap.SimpleImmutableEntry;
import java.util.HashMap;

jenetics

import static io.jenetics.engine.EvolutionResult.toBestEvolutionResult;
import static io.jenetics.engine.Limits.bySteadyFitness;

import java.util.Random;

import io.jenetics.BitGene;
import io.jenetics.Mutator;
import io.jenetics.SinglePointCrossover;
import io.jenetics.engine.Engine;
import io.jenetics.engine.EvolutionResult;

jenetics

public interface Op<T> 
    extends Function<T[], T>, Supplier<Op<T>>
{
    public String name();
    public int arity();
    public T apply(T[] args);
}

jenetics

final ISeq<Op<Double>> terminals = ISeq.of(
    Var.of("x", 0), Var.of("y", 1), Var.of("z", 2)
);