Examples of java.util.Random.nextFloat()

java.util.Random.nextFloat()
Returns the next pseudorandom, uniformly distributed {@code float}value between {@code 0.0} and {@code 1.0} from this randomnumber generator's sequence.
The general contract of {@code nextFloat} is that one{@code float} value, chosen (approximately) uniformly from therange {@code 0.0f} (inclusive) to {@code 1.0f} (exclusive), ispseudorandomly generated and returned. All 2²⁴ possible {@code float} valuesof the form m x 2^-24, where m is a positive integer less than 2²⁴ , are produced with (approximately) equal probability.
The method {@code nextFloat} is implemented by class {@code Random}as if by:
```
  {@code}public float nextFloat()  return next(24) / ((float)(1 << 24)); }}
```
The hedge "approximately" is used in the foregoing description only because the next method is only approximately an unbiased source of independently chosen bits. If it were a perfect source of randomly chosen bits, then the algorithm shown would choose {@code float}values from the stated range with perfect uniformity.
[In early versions of Java, the result was incorrectly calculated as:
```
  {@code return next(30) / ((float)(1 << 30));}
```
This might seem to be equivalent, if not better, but in fact it introduced a slight nonuniformity because of the bias in the rounding of floating-point numbers: it was slightly more likely that the low-order bit of the significand would be 0 than that it would be 1.] @return the next pseudorandom, uniformly distributed {@code float}value between {@code 0.0} and {@code 1.0} from thisrandom number generator's sequence

    final RepeatingTokenStream ts = new RepeatingTokenStream(val);


    Analyzer analyzer = new Analyzer() {
      @Override
      public TokenStream tokenStream(String fieldName, Reader reader) {
        if (random.nextFloat() < percentDocs) ts.num = random.nextInt(maxTF)+1;
        else ts.num=0;
        return ts;
      }
    };

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        break;
      case 'L':
        result.add(r.nextLong());
        break;
      case 'F':
        result.add(r.nextFloat());
        break;
      case 'D':
        result.add(r.nextDouble());
        break;
      case 'S':

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    void genData(Encoder e) throws IOException {
      e.writeArrayStart();
      e.setItemCount(count);
      Random r = newRandom();
      for (int i = 0; i < count; i++) {
        e.writeFloat(r.nextFloat());
      }
      e.writeArrayEnd();
    }


    @Override

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    void genData(Encoder e) throws IOException {
      e.writeArrayStart();
      e.setItemCount(count);
      Random r = newRandom();
      for (int i = 0; i < count; i++) {
        e.writeDouble(r.nextFloat());
      }
      e.writeArrayEnd();
    }
    @Override
    void readInternal(Decoder d) throws IOException {

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    {
      final long seed = random().nextLong();
      Random r = new Random(seed);
      CommonTermsQuery left = new CommonTermsQuery(randomOccur(r),
          randomOccur(r), r.nextFloat(), r.nextBoolean());
      int leftTerms = atLeast(r, 2);
      for (int i = 0; i < leftTerms; i++) {
        left.add(new Term(_TestUtil.randomRealisticUnicodeString(r), _TestUtil
            .randomRealisticUnicodeString(r)));
      }

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      left.setHighFreqMinimumNumberShouldMatch(r.nextInt(4));
      left.setLowFreqMinimumNumberShouldMatch(r.nextInt(4));
      
      r = new Random(seed);
      CommonTermsQuery right = new CommonTermsQuery(randomOccur(r),
          randomOccur(r), r.nextFloat(), r.nextBoolean());
      int rightTerms = atLeast(r, 2);
      for (int i = 0; i < rightTerms; i++) {
        right.add(new Term(_TestUtil.randomRealisticUnicodeString(r), _TestUtil
            .randomRealisticUnicodeString(r)));
      }

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      float[] orig = new float[1024];
      MutableSparseFloatArray fromEmpty = new MutableSparseFloatArray(new float[1024]);
      float density = 0.2f;
      int idx = 0;
      while (rand.nextFloat() > density) {
        idx++;
      }
      while (idx < orig.length) {
        float val = rand.nextFloat();
        orig[idx] = val;

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      int idx = 0;
      while (rand.nextFloat() > density) {
        idx++;
      }
      while (idx < orig.length) {
        float val = rand.nextFloat();
        orig[idx] = val;
        fromEmpty.set(idx, val);
        idx += 1;
        while (rand.nextDouble() > density) {
          idx++;

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      MutableSparseFloatArray fromPartial = new MutableSparseFloatArray(copy);


      // do 128 modifications
      int mods = 128;
      for (int i = 0; i < mods; i++) {
        float val = rand.nextFloat();
        idx = rand.nextInt(orig.length);
        orig[idx] = val;
        fromEmpty.set(idx, val);
        fromPartial.set(idx, val);
      }

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        int idx = r.nextInt(orig.length);
        if (r.nextBoolean()) {
          assertTrue("orig " + orig[idx] + " not the same as arr " + arr.get(idx) + " at idx="
              + idx, orig[idx] == arr.get(idx));
        } else {
          float val = r.nextFloat();
          orig[idx] = val;
          arr.set(idx, val);
        }
      }

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