Java Random.nextGaussian方法代码示例

import java.util.Random; //导入方法依赖的package包/类
private static double salesRateAdjustment(long time, Random random){
    Calendar cal = Calendar.getInstance();
    cal.setTimeInMillis(time);
    double x = cal.get(Calendar.DAY_OF_YEAR);
    //if you graph out this rate equation you will see two peaks and two troughs with some valleys
    //but summed over 365 days it will add up to zero so the sales rate adjustement, if averaged over a year period (365 days)
    //will be zero. Basically this is to simulate the ups and downs in sales in a year
    double rate =  (-1.0/3.0) * Math.sin(x * ((4.0 * Math.PI)/365.0)) - (1.0/13.0) * Math.sin(x *(32.0 * Math.PI)/365.0);
    
    double noise = (10 + random.nextGaussian())/10;
    if (Math.abs(noise) < 2.0){
        rate = rate * noise;
    }
    
    return rate;
    
    
}
 

import java.util.Random; //导入方法依赖的package包/类
double[] createNoisySeasonalData(int length, int period, double seasonalAmplitude, double trendSlope,
		double noiseSigma, long seed) {

	this.seed = seed;
	Random rand = new Random(seed);

	double[] y = new double[length];
	double dx = 2 * Math.PI / period;
	for (int i = 0; i < length; ++i) {
		double x = i * dx;
		double e = noiseSigma * rand.nextGaussian();
		y[i] = trendSlope * x + seasonalAmplitude * Math.sin(x) + e;
	}

	return y;
}
 

import java.util.Random; //导入方法依赖的package包/类
public static double[] createDoubleArrayGaussian(int size) {
    Random rand = new Random(0);
    double[] array = new double[size];
    for (int i = 0; i < size; ++i) {
        array[i] = rand.nextGaussian();
    }
    return array;
}
 

import java.util.Random; //导入方法依赖的package包/类
public double[] createArguments(Random random) {
	double[] args = new double[coordinates.length];
	for (int i = 0; i < args.length; i++) {
		args[i] = coordinates[i] + random.nextGaussian() * sigmas[i];
	}
	return args;
}
 

import java.util.Random; //导入方法依赖的package包/类
@Override
public DMatrix initWeights(int outputSize, int inputSize)
{
    Random rand = new Random();
    double[][] values = new double[inputSize][outputSize];
    for(double[] row : values)
    {
        for(int j = 0; j < outputSize; j++)
        {
            row[j] = rand.nextGaussian();
        }
    }
    return new DMatrix(values);
}
 

import java.util.Random; //导入方法依赖的package包/类
public void getH1nH2(){
	double price = 0.0; 
	alpha = 2.0/(100.0 + 1.0);
	alphaWeight = Math.exp(-alpha);
	runner = new Runner[runner.length];
	for( int i = 0; i < runner.length; ++i ){
		runner[i] = new Runner(0.025/100.0 + 0.05/100.0*(double)i, 0.025/100.0 + 0.05/100.0*(double)i, price, "JustFake");
		runner[i].type = (i%2 == 0 ? 1 : -1);
		prevState[i] = (runner[i].type == 1 ? 1 : 0);
	}
	
	double total1 = 0.0, total2 = 0.0;
	Random rand = new Random(1);
	double dt = 1.0/Math.sqrt(1000000.0);
	double sigma = 0.25; // 25%
	for( int i = 0; i < 100000000; ++i ){
		price += sigma*dt*rand.nextGaussian();
		for( int j= 0; j < runner.length; ++j ){
			if( Math.abs(runner[j].run(price)) == 1 ){ // this is OK for simulated prices
				double myProbs = getProbs(j);
				total1 = total1*alphaWeight + (1.0 - alphaWeight)*(-Math.log(myProbs));
				total2 = total2*alphaWeight + (1.0 - alphaWeight)*Math.pow(Math.log(myProbs), 2.0);
			}
		}
	}
	H1 = total1;
	H2 = total2 - H1*H1;
	System.out.println("H1:" + H1 + " H2:" + H2);
}
 

import java.util.Random; //导入方法依赖的package包/类
/**
 * Repeated calls to nextGaussian produce at least two distinct results
 */
public void testNextGaussian() {
    Random r = new Random();
    double f = r.nextGaussian();
    int i = 0;
    while (i < NCALLS && r.nextGaussian() == f)
        ++i;
    assertTrue(i < NCALLS);
}
 

import java.util.Random; //导入方法依赖的package包/类
@Test
public void testOneDimensionalPosition() {
	final String name = "pos";
	final int index = 4;
	final double pos = -79.0;
	mockIterator.next = new MapPosition(name, index, pos);

	Random random = new Random(RANDOM_SEED);
	double expectedPos = pos + random.nextGaussian() * STD_DEV;
	IPosition expected = new MapPosition(name, index, expectedPos);

	IPosition actual = randomOffsetDecorator.next();
	assertEquals(expected, actual);
}
 

import java.util.Random; //导入方法依赖的package包/类
public static int getRandomNumberAroundSomething(Random generator, int center, int deviation)
{
    if (center == 0)
        return 0;
    if (deviation == 0)
        return center;

    double val = generator.nextGaussian();

    // first we scale to account for the standard deviation we need
    // here we just use half of the average
    // val *= center * 0.5;
    val *= deviation;

    // Shift it to the center we want
    val += center;
    // make any possible negative value, positive
    val = (val < 0) ? -val : val;
    
    // and if 0 make it 1
    //val = (val == 0) ? 1 : val;

    // if less than 1 make it 1
    val = (val < 1) ? 1 : val;
    
    return (int) val;
}
 

import java.util.Random; //导入方法依赖的package包/类
@EventHandler(priority = EventPriority.HIGHEST, ignoreCancelled = true)
public void dispenserNukes(BlockTransformEvent event) {
    BlockState oldState = event.getOldState();
    if(oldState instanceof Dispenser &&
       this.properties.dispenserNukeLimit > 0 &&
       this.properties.dispenserNukeMultiplier > 0 &&
       event.getCause() instanceof EntityExplodeEvent) {

        EntityExplodeEvent explodeEvent = (EntityExplodeEvent) event.getCause();
        Dispenser dispenser = (Dispenser) oldState;
        int tntLimit = Math.round(this.properties.dispenserNukeLimit / this.properties.dispenserNukeMultiplier);
        int tntCount = 0;

        for(ItemStack stack : dispenser.getInventory().contents()) {
            if(stack != null && stack.getType() == Material.TNT) {
                int transfer = Math.min(stack.getAmount(), tntLimit - tntCount);
                if(transfer > 0) {
                    stack.setAmount(stack.getAmount() - transfer);
                    tntCount += transfer;
                }
            }
        }

        tntCount = (int) Math.ceil(tntCount * this.properties.dispenserNukeMultiplier);

        for(int i = 0; i < tntCount; i++) {
            TNTPrimed tnt = this.getMatch().getWorld().spawn(BlockUtils.base(dispenser), TNTPrimed.class);

            tnt.setFuseTicks(10 + this.getMatch().getRandom().nextInt(10)); // between 0.5 and 1.0 seconds, same as vanilla TNT chaining

            Random random = this.getMatch().getRandom();
            Vector velocity = new Vector(random.nextGaussian(), random.nextGaussian(), random.nextGaussian()); // uniform random direction
            velocity.normalize().multiply(0.5 + 0.5 * random.nextDouble());
            tnt.setVelocity(velocity);

            callPrimeEvent(tnt, explodeEvent.getEntity(), false);
        }
    }
}
 

import java.util.Random; //导入方法依赖的package包/类
@Override
    public void resetFilter() {
        filter = new ParticleFilter(dynamic, measurement, average);
        
        Random r = new Random();
        for(int i = 0; i < particlesCount; i++) {
//                double x = (chip.getSizeX()/2) * (r.nextDouble()*2 - 1) + chip.getSizeX()/2;
//                double y = (chip.getSizeX()/2) * (r.nextDouble()*2 - 1) + chip.getSizeX()/2;
                double x = r.nextGaussian() + startPositionX;
                double y = r.nextGaussian() + startPositionY;
                filter.addParticle(new SimpleParticle(x, y));
        }    
    }
 

import java.util.Random; //导入方法依赖的package包/类
/**
 * Generates a new sinus function attribute for all given attribute peaks. Since the frequency
 * cannot be calculated exactly (leakage, aliasing), several new attribute may be added for each
 * peak. These additional attributes are randomly chosen (uniformly in epsilon range, uniformly
 * without nu, gaussian with epsilon as standard deviation)
 */
public void generateSinusFunctions(ExampleSet exampleSet, List<AttributePeak> attributes, Random random)
		throws GenerationException {
	if (attributes.size() > 0) {
		Collections.sort(attributes);
		double totalMaxEvidence = attributes.get(0).getEvidence();

		Iterator<AttributePeak> a = attributes.iterator();
		while (a.hasNext()) {
			AttributePeak ae = a.next();
			if (ae.getEvidence() > MIN_EVIDENCE * totalMaxEvidence) {
				for (int i = 0; i < attributesPerPeak; i++) {
					double frequency = ae.getFrequency();
					switch (adaptionType) {
						case UNIFORMLY:
							if (attributesPerPeak != 1) {
								frequency = (double) i / (double) (attributesPerPeak - 1) * 2.0d * epsilon * frequency
										+ (frequency - epsilon * frequency);
							}
							break;
						case UNIFORMLY_WITHOUT_NU:
							if (attributesPerPeak != 1) {
								frequency = (double) i / (double) (attributesPerPeak - 1) * 2.0d * epsilon
										+ (frequency - epsilon);
							}
							break;
						case GAUSSIAN:
							frequency = random.nextGaussian() * epsilon + frequency;
							break;
					}

					// frequency constant
					List frequencyResult = generateAttribute(exampleSet, new ConstantGenerator(frequency));

					// scaling with frequency
					FeatureGenerator scale = new BasicArithmeticOperationGenerator(
							BasicArithmeticOperationGenerator.PRODUCT);
					scale.setArguments(new Attribute[] { (Attribute) frequencyResult.get(0), ae.getAttribute() });
					List scaleResult = generateAttribute(exampleSet, scale);

					// calc sin
					FeatureGenerator sin = new TrigonometricFunctionGenerator(TrigonometricFunctionGenerator.SINUS);
					sin.setArguments(new Attribute[] { (Attribute) scaleResult.get(0) });
					List<Attribute> sinResult = generateAttribute(exampleSet, sin);
					for (Attribute attribute : sinResult) {
						exampleSet.getAttributes().addRegular(attribute);
					}
				}
			}
		}
	}
}
 

import java.util.Random; //导入方法依赖的package包/类
/**
 * Spawns a baby animal of the same type.
 */
private void spawnBaby()
{
    EntityAgeable entityageable = this.theAnimal.createChild(this.targetMate);

    if (entityageable != null)
    {
        EntityPlayer entityplayer = this.theAnimal.getPlayerInLove();

        if (entityplayer == null && this.targetMate.getPlayerInLove() != null)
        {
            entityplayer = this.targetMate.getPlayerInLove();
        }

        if (entityplayer != null)
        {
            entityplayer.triggerAchievement(StatList.animalsBredStat);

            if (this.theAnimal instanceof EntityCow)
            {
                entityplayer.triggerAchievement(AchievementList.breedCow);
            }
        }

        this.theAnimal.setGrowingAge(6000);
        this.targetMate.setGrowingAge(6000);
        this.theAnimal.resetInLove();
        this.targetMate.resetInLove();
        entityageable.setGrowingAge(-24000);
        entityageable.setLocationAndAngles(this.theAnimal.posX, this.theAnimal.posY, this.theAnimal.posZ, 0.0F, 0.0F);
        this.theWorld.spawnEntityInWorld(entityageable);
        Random random = this.theAnimal.getRNG();

        for (int i = 0; i < 7; ++i)
        {
            double d0 = random.nextGaussian() * 0.02D;
            double d1 = random.nextGaussian() * 0.02D;
            double d2 = random.nextGaussian() * 0.02D;
            double d3 = random.nextDouble() * (double)this.theAnimal.width * 2.0D - (double)this.theAnimal.width;
            double d4 = 0.5D + random.nextDouble() * (double)this.theAnimal.height;
            double d5 = random.nextDouble() * (double)this.theAnimal.width * 2.0D - (double)this.theAnimal.width;
            this.theWorld.spawnParticle(EnumParticleTypes.HEART, this.theAnimal.posX + d3, this.theAnimal.posY + d4, this.theAnimal.posZ + d5, d0, d1, d2, new int[0]);
        }

        if (this.theWorld.getGameRules().getBoolean("doMobLoot"))
        {
            this.theWorld.spawnEntityInWorld(new EntityXPOrb(this.theWorld, this.theAnimal.posX, this.theAnimal.posY, this.theAnimal.posZ, random.nextInt(7) + 1));
        }
    }
}
 

import java.util.Random; //导入方法依赖的package包/类
public static void bench() {
   Random r = new Random();
   RandomFloat rf = new RandomFloat();
   Stopwatch sw = new Stopwatch();
   int nf;
   float sum;
   double rate;
   for(int ntrial=0; ntrial<3; ++ntrial) {

     System.out.println();
     System.out.println("java.util.Random:");
     sw.restart();
     sum = 0.0f;
     for(nf=0; sw.time()<1.0; ++nf)
sum += r.nextFloat();
     sw.stop();
     rate = nf/sw.time();
     System.out.println("  uniform: float/s="+rate+" sum="+sum);
     sw.restart();
     sum = 0.0f;
     for(nf=0; sw.time()<1.0; ++nf)
sum += (float)r.nextGaussian();
     sw.stop();
     rate = nf/sw.time();
     System.out.println("   normal: float/s="+rate+" sum="+sum);

     System.out.println();
     System.out.println("edu.mines.jtk.util.RandomFloat:");
     sw.restart();
     sum = 0.0f;
     for(nf=0; sw.time()<1.0; ++nf)
sum += rf.uniform();
     sw.stop();
     rate = nf/sw.time();
     System.out.println("  uniform: float/s="+rate+" sum="+sum);
     sw.restart();
     sum = 0.0f;
     for(nf=0; sw.time()<1.0; ++nf)
sum += rf.normal();
     sw.stop();
     rate = nf/sw.time();
     System.out.println("   normal: float/s="+rate+" sum="+sum);
   }
 }
 

import java.util.Random; //导入方法依赖的package包/类
/**
 * Spawns a baby animal of the same type.
 */
private void spawnBaby()
{
    EntityAgeable entityageable = this.theAnimal.createChild(this.targetMate);

    final net.minecraftforge.event.entity.living.BabyEntitySpawnEvent event = new net.minecraftforge.event.entity.living.BabyEntitySpawnEvent(theAnimal, targetMate, entityageable);
    final boolean cancelled = net.minecraftforge.common.MinecraftForge.EVENT_BUS.post(event);
    entityageable = event.getChild();
    if (cancelled) {
        //Reset the "inLove" state for the animals
        this.theAnimal.setGrowingAge(6000);
        this.targetMate.setGrowingAge(6000);
        this.theAnimal.resetInLove();
        this.targetMate.resetInLove();
        return;
    }

    if (entityageable != null)
    {
        EntityPlayer entityplayer = this.theAnimal.getPlayerInLove();

        if (entityplayer == null && this.targetMate.getPlayerInLove() != null)
        {
            entityplayer = this.targetMate.getPlayerInLove();
        }

        if (entityplayer != null)
        {
            entityplayer.addStat(StatList.ANIMALS_BRED);

            if (this.theAnimal instanceof EntityCow)
            {
                entityplayer.addStat(AchievementList.BREED_COW);
            }
        }

        this.theAnimal.setGrowingAge(6000);
        this.targetMate.setGrowingAge(6000);
        this.theAnimal.resetInLove();
        this.targetMate.resetInLove();
        entityageable.setGrowingAge(-24000);
        entityageable.setLocationAndAngles(this.theAnimal.posX, this.theAnimal.posY, this.theAnimal.posZ, 0.0F, 0.0F);
        this.theWorld.spawnEntityInWorld(entityageable);
        Random random = this.theAnimal.getRNG();

        for (int i = 0; i < 7; ++i)
        {
            double d0 = random.nextGaussian() * 0.02D;
            double d1 = random.nextGaussian() * 0.02D;
            double d2 = random.nextGaussian() * 0.02D;
            double d3 = random.nextDouble() * (double)this.theAnimal.width * 2.0D - (double)this.theAnimal.width;
            double d4 = 0.5D + random.nextDouble() * (double)this.theAnimal.height;
            double d5 = random.nextDouble() * (double)this.theAnimal.width * 2.0D - (double)this.theAnimal.width;
            this.theWorld.spawnParticle(EnumParticleTypes.HEART, this.theAnimal.posX + d3, this.theAnimal.posY + d4, this.theAnimal.posZ + d5, d0, d1, d2, new int[0]);
        }

        if (this.theWorld.getGameRules().getBoolean("doMobLoot"))
        {
            this.theWorld.spawnEntityInWorld(new EntityXPOrb(this.theWorld, this.theAnimal.posX, this.theAnimal.posY, this.theAnimal.posZ, random.nextInt(7) + 1));
        }
    }
}