Examples of java.util.Random.nextDouble()

java.util.Random.nextDouble()
Returns the next pseudorandom, uniformly distributed {@code double} value between {@code 0.0} and{@code 1.0} from this random number generator's sequence.
The general contract of {@code nextDouble} is that one{@code double} value, chosen (approximately) uniformly from therange {@code 0.0d} (inclusive) to {@code 1.0d} (exclusive), ispseudorandomly generated and returned.
The method {@code nextDouble} is implemented by class {@code Random}as if by:
```
  {@code}public double nextDouble()  return (((long)next(26) << 27) + next(27)) / (double)(1L << 53); }}
```
The hedge "approximately" is used in the foregoing description only because the {@code next} method is only approximately an unbiasedsource of independently chosen bits. If it were a perfect source of randomly chosen bits, then the algorithm shown would choose {@code double} values from the stated range with perfect uniformity.
[In early versions of Java, the result was incorrectly calculated as:
```
  {@code return (((long)next(27) << 27) + next(27)) / (double)(1L << 54);}
```
This might seem to be equivalent, if not better, but in fact it introduced a large nonuniformity because of the bias in the rounding of floating-point numbers: it was three times as likely that the low-order bit of the significand would be 0 than that it would be 1! This nonuniformity probably doesn't matter much in practice, but we strive for perfection.] @return the next pseudorandom, uniformly distributed {@code double}value between {@code 0.0} and {@code 1.0} from thisrandom number generator's sequence @see Math#random

     */
    double[] createRealData(final int n) {
        final Random random = new Random(SEED);
        final double[] data = new double[n];
        for (int i = 0; i < n; i++) {
            data[i] = 2.0 * random.nextDouble() - 1.0;
        }
        return data;
    }


    /*

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    private static Complex[] createComplexData(final int n) {
        final Random random = new Random(SEED);
        final Complex[] data = new Complex[n];
        for (int i = 0; i < n; i++) {
            final double re = 2.0 * random.nextDouble() - 1.0;
            final double im = 2.0 * random.nextDouble() - 1.0;
            data[i] = new Complex(re, im);
        }
        return data;
    }

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    private static Complex[] createComplexData(final int n) {
        final Random random = new Random(SEED);
        final Complex[] data = new Complex[n];
        for (int i = 0; i < n; i++) {
            final double re = 2.0 * random.nextDouble() - 1.0;
            final double im = 2.0 * random.nextDouble() - 1.0;
            data[i] = new Complex(re, im);
        }
        return data;
    }

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        for (int i = 20; i <= 5000; i += 20) {
            
            ArrayList<Point> pts = new ArrayList<Point>();
            
            for(int j = 0; j < i; j++) {
                pts.add(new Point(rand.nextDouble()*10, rand.nextDouble()*10));
            }
            
            double start = Calendar.getInstance().getTimeInMillis();
            
            Delaunay.bruteForce(pts);

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        for (int i = 20; i <= 5000; i += 20) {
            
            ArrayList<Point> pts = new ArrayList<Point>();
            
            for(int j = 0; j < i; j++) {
                pts.add(new Point(rand.nextDouble()*10, rand.nextDouble()*10));
            }
            
            double start = Calendar.getInstance().getTimeInMillis();
            
            Delaunay.bruteForce(pts);

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        for (int i = 5020; i <= 8000; i += 20) {
            
            ArrayList<Point> pts = new ArrayList<Point>();
            
            for(int j = 0; j < i; j++) {
                pts.add(new Point(rand.nextDouble()*10, rand.nextDouble()*10));
            }
            
            double start = Calendar.getInstance().getTimeInMillis();
            
            Delaunay.randomizedIncremental(pts);

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        for (int i = 5020; i <= 8000; i += 20) {
            
            ArrayList<Point> pts = new ArrayList<Point>();
            
            for(int j = 0; j < i; j++) {
                pts.add(new Point(rand.nextDouble()*10, rand.nextDouble()*10));
            }
            
            double start = Calendar.getInstance().getTimeInMillis();
            
            Delaunay.randomizedIncremental(pts);

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        for (int repeat = 0; repeat < 1000; repeat++) {
            for (int i = 2; i <= 20; i++) {
                ArrayList<Segment> segments = new ArrayList<Segment>();


                for(int j = 0; j < i; j++) {
                    segments.add(new Segment(new Point(rand.nextDouble()*100, rand.nextDouble()*100),
                                             new Point(rand.nextDouble()*100, rand.nextDouble()*100)));
                }


                assertTrue(SegmentsIntersect.any(segments) ==
                            SegmentsIntersect.any_Naive(segments));

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        for (int repeat = 0; repeat < 1000; repeat++) {
            for (int i = 2; i <= 20; i++) {
                ArrayList<Segment> segments = new ArrayList<Segment>();


                for(int j = 0; j < i; j++) {
                    segments.add(new Segment(new Point(rand.nextDouble()*100, rand.nextDouble()*100),
                                             new Point(rand.nextDouble()*100, rand.nextDouble()*100)));
                }


                assertTrue(SegmentsIntersect.any(segments) ==
                            SegmentsIntersect.any_Naive(segments));

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            for (int i = 2; i <= 20; i++) {
                ArrayList<Segment> segments = new ArrayList<Segment>();


                for(int j = 0; j < i; j++) {
                    segments.add(new Segment(new Point(rand.nextDouble()*100, rand.nextDouble()*100),
                                             new Point(rand.nextDouble()*100, rand.nextDouble()*100)));
                }


                assertTrue(SegmentsIntersect.any(segments) ==
                            SegmentsIntersect.any_Naive(segments));
            }

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