java.util.stream.DoubleStream Java Examples

@Nullable
private static Number reduceNumbers(List<? extends Number> list,
		Function<DoubleStream, Double> opDouble, Function<LongStream, Long> opLong) {
	list = list.stream().filter(Objects::nonNull).collect(toList());

	if (list.isEmpty()) return null;

	Class<?> numberClass = list.get(0).getClass();
	if (isFloatingPointNumber(numberClass)) {
		return convert(numberClass,
				opDouble.apply(list.stream().mapToDouble(Number::doubleValue)));
	} else if (isIntegerNumber(numberClass)) {
		return convert(numberClass,
				opLong.apply(list.stream().mapToLong(Number::longValue)));
	} else {
		throw new IllegalArgumentException(
				"Unsupported objects of type: " + numberClass.getName());
	}
}
 

@Override
public List<PotentialAssignment> getValueSources(final ParameterSignature sig) {
	final DoubleData doubledata = sig.getAnnotation(DoubleData.class);
	DoubleStream stream = Arrays.stream(doubledata.vals());

	if(doubledata.angle()) {
		stream = DoubleStream.of(0d, Math.PI / 2d, Math.PI, 3d * Math.PI / 2d, 2d * Math.PI, -Math.PI / 2d, -Math.PI,
			-3d * Math.PI / 2d, -2d * Math.PI, 1.234, -1.234, 3d * Math.PI, -3d * Math.PI);
	}

	if(doubledata.bads()) {
		stream = DoubleStream.concat(stream, DoubleStream.of(Double.NaN, Double.NEGATIVE_INFINITY, Double.POSITIVE_INFINITY));
	}

	return stream.mapToObj(i -> PotentialAssignment.forValue("", i)).collect(Collectors.toList());
}
 

@NotNull
static List<SomaticPeak> findPeaks(@NotNull final List<Double> sample) {
    final KernelEstimator estimator = new KernelEstimator(0.001, KERNEL_BANDWIDTH);
    sample.forEach(x -> estimator.addValue(x, 1.0D));

    final double[] vafs = IntStream.rangeClosed(0, 51).mapToDouble(x -> x / 100d).toArray();
    final double[] densities = DoubleStream.of(vafs).map(estimator::getProbability).toArray();

    final List<SomaticPeak> results = Lists.newArrayList();
    for (int i = 1; i < densities.length - 1; i++) {
        double density = densities[i];
        if (Doubles.greaterThan(density, densities[i - 1]) && Doubles.greaterThan(density, densities[i + 1])) {
            final double alleleFrequency = vafs[i];
            final int peakCount = count(alleleFrequency, sample);
            final SomaticPeak peak = ImmutableSomaticPeak.builder().alleleFrequency(alleleFrequency).count(peakCount).build();
            LOGGER.info("Discovered peak {}", peak);
            results.add(peak);
        }
    }

    return results;
}
 

public void testDoubleSize() {
    assertSized(DoubleStream.concat(
            IntStream.range(0, Integer.MAX_VALUE).mapToDouble(i -> i),
            IntStream.range(0, Integer.MAX_VALUE).mapToDouble(i -> i)));

    assertUnsized(DoubleStream.concat(
            LongStream.range(0, Long.MAX_VALUE).mapToDouble(i -> i),
            LongStream.range(0, Long.MAX_VALUE).mapToDouble(i -> i)));

    assertUnsized(DoubleStream.concat(
            LongStream.range(0, Long.MAX_VALUE).mapToDouble(i -> i),
            DoubleStream.iterate(0, i -> i + 1)));

    assertUnsized(DoubleStream.concat(
            DoubleStream.iterate(0, i -> i + 1),
            LongStream.range(0, Long.MAX_VALUE).mapToDouble(i -> i)));
}
 

private static void boxed(){
    //IntStream.range(1, 3).map(Integer::shortValue)        //compile error
    //                     .forEach(System.out::print);

    IntStream.range(1, 3).boxed().map(Integer::shortValue)
            .forEach(System.out::print);                    //prints: 12
    System.out.println();
    //LongStream.range(1, 3).map(Long::shortValue)          //compile error
    //                      .forEach(System.out::print);

    LongStream.range(1, 3).boxed().map(Long::shortValue)
            .forEach(System.out::print);                    //prints: 12
    System.out.println();
    //DoubleStream.of(1).map(Double::shortValue)            //compile error
    //                  .forEach(System.out::print);

    DoubleStream.of(1).boxed().map(Double::shortValue)
            .forEach(System.out::print);                    //prints: 1

}
 

@Test
public void testAbs() {
    try (NDManager manager = NDManager.newBaseManager()) {
        double[] data = {1.0, -2.12312, -3.5784, -4.0, 5.0, -223.23423};
        NDArray array = manager.create(data);
        data = DoubleStream.of(data).map(Math::abs).toArray();
        NDArray expected = manager.create(data);
        Assertions.assertAlmostEquals(array.abs(), expected);
        // test multi-dim
        data = new double[] {1.2, 98.34, 2.34, -0.456, 2, -22};
        array = manager.create(data, new Shape(2, 1, 1, 3));
        data = DoubleStream.of(data).map(Math::abs).toArray();
        expected = manager.create(data, new Shape(2, 1, 1, 3));
        Assertions.assertAlmostEquals(array.abs(), expected);
        // test scalar
        array = manager.create(-0.00001f);
        expected = manager.create(0.00001f);
        Assertions.assertAlmostEquals(array.abs(), expected);
        // test zero-dim
        array = manager.create(new Shape(0, 0, 2, 0));
        Assert.assertEquals(array.abs(), array);
    }
}
 

@Test
public void testAllForeground() {
	// SETUP
	final double scalingPow = DoubleStream.generate(() -> SCALING).limit(
		DIMENSIONS).reduce((i, j) -> i * j).orElse(0);
	final double[] expectedCounts = DoubleStream.iterate(1.0, i -> i *
		scalingPow).map(Math::log).limit(ITERATIONS).toArray();
	final Img<BitType> img = ArrayImgs.bits(TEST_DIMS);
	img.forEach(BitType::setOne);

	// EXECUTE
	final List<ValuePair<DoubleType, DoubleType>> points = ops.topology()
		.boxCount(img, MAX_SIZE, MIN_SIZE, SCALING);

	// VERIFY
	for (int i = 0; i < ITERATIONS; i++) {
		assertEquals(EXPECTED_SIZES[i], points.get(i).a.get(), 1e-12);
		assertEquals(expectedCounts[i], points.get(i).b.get(), 1e-12);
	}
}
 

/**
 * Test box counting with a hyper cube and one grid translation (should find a
 * better fit than in @see {@link #testHyperCube()})
 */
@Test
public void testHyperCubeTranslations() {
	final double[] expectedSizes = DoubleStream.of(4, 2, 1).map(i -> -Math.log(
		i)).toArray();
	final double[] expectedCounts = DoubleStream.of(1, 1, 16).map(Math::log)
		.toArray();
	final Img<BitType> img = ArrayImgs.bits(4, 4, 4, 4);
	final IntervalView<BitType> hyperView = Views.offsetInterval(img,
		new long[] { 1, 1, 1, 1 }, new long[] { 2, 2, 2, 2 });
	hyperView.forEach(BitType::setOne);

	// EXECUTE
	final List<ValuePair<DoubleType, DoubleType>> points = ops.topology()
		.boxCount(img, 4L, 1L, 2.0, 1L);

	// VERIFY
	for (int i = 0; i < expectedSizes.length; i++) {
		assertEquals(expectedSizes[i], points.get(i).a.get(), 1e-12);
		assertEquals(expectedCounts[i], points.get(i).b.get(), 1e-12);
	}
}
 

@Test(dataProvider = "readCountOnlyWithDiverseShapeData")
public void testCalculateReducedPanelAndPInversesUsingJollifesRule(final ReadCountCollection readCounts) {
    final JavaSparkContext ctx = SparkContextFactory.getTestSparkContext();
    final ReductionResult result = HDF5PCACoveragePoNCreationUtils.calculateReducedPanelAndPInverses(readCounts, OptionalInt.empty(), NULL_LOGGER, ctx);
    final RealMatrix counts = readCounts.counts();
    Assert.assertNotNull(result);
    Assert.assertNotNull(result.getPseudoInverse());
    Assert.assertNotNull(result.getReducedCounts());
    Assert.assertNotNull(result.getReducedPseudoInverse());
    Assert.assertNotNull(result.getAllSingularValues());
    Assert.assertEquals(counts.getColumnDimension(), result.getAllSingularValues().length);
    Assert.assertEquals(result.getReducedCounts().getRowDimension(), counts.getRowDimension());
    final int eigensamples = result.getReducedCounts().getColumnDimension();
    final Mean mean = new Mean();
    final double meanSingularValue = mean.evaluate(result.getAllSingularValues());
    final double threshold = HDF5PCACoveragePoNCreationUtils.JOLLIFES_RULE_MEAN_FACTOR * meanSingularValue;
    final int expectedEigensamples = (int) DoubleStream.of(result.getAllSingularValues()).filter(d -> d >= threshold).count();
    Assert.assertTrue(eigensamples <= counts.getColumnDimension());
    Assert.assertEquals(eigensamples, expectedEigensamples);
    assertPseudoInverse(counts, result.getPseudoInverse());
    assertPseudoInverse(result.getReducedCounts(), result.getReducedPseudoInverse());
}
 

@Override
protected double[] createNumbers(SplittableRandom rng) {
    DoubleSupplier generator;
    if ("pi".equals(type)) {
        generator = () -> rng.nextDouble() * 2 * Math.PI - Math.PI;
    } else if ("pi/2".equals(type)) {
        generator = () -> rng.nextDouble() * Math.PI - Math.PI / 2;
    } else if ("random".equals(type)) {
        generator = () -> createRandomNumber(rng);
    } else if ("edge".equals(type)) {
        generator = () -> createEdgeNumber(rng);
    } else {
        throw new IllegalStateException("Unknown number type: " + type);
    }
    return DoubleStream.generate(generator).limit(getSize()).toArray();
}
 

private static void sumAndAverage() {

        System.out.println();
        int sum = IntStream.empty().sum();
        System.out.println(sum);  //prints: 0
        sum = IntStream.range(1, 3).sum();
        System.out.println(sum);  //prints: 3
        double av = IntStream.empty().average().orElse(0);
        System.out.println(av);   //prints: 0.0
        av = IntStream.range(1, 3).average().orElse(0);
        System.out.println(av);   //prints: 1.5

        long suml = LongStream.range(1, 3).sum();
        System.out.println(suml);  //prints: 3
        double avl = LongStream.range(1, 3).average().orElse(0);
        System.out.println(avl);   //prints: 1.5

        double sumd = DoubleStream.of(1, 2).sum();
        System.out.println(sumd);  //prints: 3.0
        double avd = DoubleStream.of(1, 2).average().orElse(0);
        System.out.println(avd);   //prints: 1.5

    }
 

@Test(dataProvider = "DoubleStream.limit")
public void testDoubleUnorderedIteration(String description, UnaryOperator<DoubleStream> fs) {
    // Source is a right-balanced tree of infinite size
    TestData.OfDouble iterator = TestData.Factory.ofDoubleSupplier(
            "[1.0, 2.0, 3.0, ...]", () -> DoubleStream.iterate(1, i -> i + 1));

    // Ref
    withData(iterator).
            stream(s -> fs.apply(s.unordered())).
            resultAsserter(unorderedAsserter()).
            exercise();
}
 

/**
 * Computes the 2-sided pvalue of the Fisher's exact test on a normalized table that ensures that the sum of
 * all four entries is less than 2 * 200.
 */
public static double twoSidedPValue(final int[][] normalizedTable) {
    Utils.nonNull(normalizedTable);
    Utils.validateArg(normalizedTable.length == 2, () -> "input must be 2x2 " + Arrays.deepToString(normalizedTable));
    Utils.validateArg(normalizedTable[0] != null && normalizedTable[0].length == 2, () -> "input must be 2x2 " + Arrays.deepToString(normalizedTable));
    Utils.validateArg(normalizedTable[1] != null && normalizedTable[1].length == 2, () -> "input must be 2x2 " + Arrays.deepToString(normalizedTable));

    //Note: this implementation follows the one in R base package
    final int[][] x= normalizedTable;
    final int m = x[0][0] + x[0][1];
    final int n = x[1][0] + x[1][1];
    final int k = x[0][0] + x[1][0];
    final int lo = Math.max(0, k - n);
    final int hi = Math.min(k, m);
    final IndexRange support = new IndexRange(lo, hi + 1);

    if (support.size() <= 1){     //special case, support has only one value
        return 1.0;
    }

    final AbstractIntegerDistribution dist = new HypergeometricDistribution(null, m+n, m, k);
    final double[] logds = support.mapToDouble(dist::logProbability);
    final double threshold = logds[x[0][0] - lo] * REL_ERR;
    final double[] log10ds = DoubleStream.of(logds).filter(d -> d <= threshold).map(MathUtils::logToLog10).toArray();
    final double pValue = MathUtils.sumLog10(log10ds);

    // min is necessary as numerical precision can result in pValue being slightly greater than 1.0
    return Math.min(pValue, 1.0);
}
 

@Test(dataProvider = "DoubleStream.limit")
public void testDoubleSubsizedWithRange(String description, UnaryOperator<DoubleStream> fs) {
    // Range is [0, 2^53), splits are SUBSIZED
    // Such a size will induce out of memory errors for incorrect
    // slice implementations
    withData(doubles()).
            stream(s -> fs.apply(s)).
            without(DoubleStreamTestScenario.PAR_STREAM_TO_ARRAY_CLEAR_SIZED).
            exercise();
}
 

@Test(dataProvider = "StreamTestData<Integer>", dataProviderClass = StreamTestDataProvider.class)
public void testOp(String name, TestData.OfRef<Integer> data) {
    Collection<Integer> result = exerciseOpsInt(
            data,
            Stream::distinct,
            IntStream::distinct,
            LongStream::distinct,
            DoubleStream::distinct);

    assertUnique(result);
    assertTrue((data.size() > 0) ? result.size() > 0 : result.size() == 0);
    assertTrue(result.size() <= data.size());
}
 

@Test(dataProvider = "DoubleStream.limit")
public void testDoubleUnorderedFinite(String description, UnaryOperator<DoubleStream> fs) {
    // Range is [0, 1L << 53), splits are SUBSIZED
    // Such a size will induce out of memory errors for incorrect
    // slice implementations
    // Upper bound ensures values mapped to doubles will be unique
    withData(doubles()).
            stream(s -> fs.apply(s.filter(i -> true).unordered())).
            resultAsserter(unorderedAsserter()).
            exercise();
}
 

@Test(dataProvider = "sizes")
public void testDoubleAfterBuilding(int size) {
    DoubleStream.Builder sb = DoubleStream.builder();
    IntStream.range(0, size).asDoubleStream().forEach(sb);
    sb.build();

    checkISE(() -> sb.accept(1));
    checkISE(() -> sb.add(1));
    checkISE(() -> sb.build());
}
 

@Test(dataProvider = "DoubleStream.limit")
public void testDoubleSubsizedWithRange(String description, UnaryOperator<DoubleStream> fs) {
    // Range is [0, 2^53), splits are SUBSIZED
    // Such a size will induce out of memory errors for incorrect
    // slice implementations
    withData(doubles()).
            stream(s -> fs.apply(s)).
            without(DoubleStreamTestScenario.CLEAR_SIZED_SCENARIOS).
            exercise();
}
 

@Test(dataProvider = "DoubleStream.limit")
public void testDoubleSubsizedWithRange(String description, UnaryOperator<DoubleStream> fs) {
    // Range is [0, 2^53), splits are SUBSIZED
    // Such a size will induce out of memory errors for incorrect
    // slice implementations
    withData(doubles()).
            stream(s -> fs.apply(s)).
            without(DoubleStreamTestScenario.PAR_STREAM_TO_ARRAY_CLEAR_SIZED).
            exercise();
}
 

@Test(dataProvider = "DoubleStream.limit")
public void testDoubleUnorderedGenerator(String description, UnaryOperator<DoubleStream> fs) {
    // Source is spliterator of infinite size
    TestData.OfDouble generator = TestData.Factory.ofDoubleSupplier(
            "[1.0, 1.0, ...]", () -> DoubleStream.generate(() -> 1.0));

    withData(generator).
            stream(s -> fs.apply(s.filter(i -> true).unordered())).
            exercise();
}
 

@Test
public void demo() {

    // Type-safe column identifiers
    final StringColumnId NAME = StringColumnId.of("Name");
    final CategoryColumnId COLOR = CategoryColumnId.of("Color");
    final DoubleColumnId SERVING_SIZE = DoubleColumnId.of("Serving Size (g)");

    // Convenient column creation
    StringColumn nameColumn = StringColumn.ofAll(NAME, "Banana", "Blueberry", "Lemon", "Apple");
    CategoryColumn colorColumn = CategoryColumn.ofAll(COLOR, "Yellow", "Blue", "Yellow", "Green");
    DoubleColumn servingSizeColumn = DoubleColumn.ofAll(SERVING_SIZE, 118, 148, 83, 182);

    // Grouping columns into a data frame
    DataFrame dataFrame = DataFrame.ofAll(nameColumn, colorColumn, servingSizeColumn);

    // Typed random access to individual values (based on rowIndex / columnId)
    String lemon = dataFrame.getValueAt(2, NAME);
    double appleServingSize = dataFrame.getValueAt(3, SERVING_SIZE);

    // Typed stream-based access to all values
    DoubleStream servingSizes = servingSizeColumn.valueStream();
    double maxServingSize = servingSizes.summaryStatistics().getMax();

    // Smart column implementations
    Set<String> colors = colorColumn.getCategories();

}
 

@Test(groups = { "serialization-hostile" })
public void testDoubleDefaultClose() {
    AtomicBoolean isClosed = new AtomicBoolean();
    DoubleStream s = DoubleStream.of(1, 2, 3).onClose(() -> isClosed.set(true));
    try (DoubleStream ds = DefaultMethodStreams.delegateTo(s).takeWhile(e -> e < 3)) {
        ds.count();
    }
    assertTrue(isClosed.get());
}
 

@Test(dataProvider = "sizes")
public void testDoubleAfterBuilding(int size) {
    DoubleStream.Builder sb = DoubleStream.builder();
    IntStream.range(0, size).asDoubleStream().forEach(sb);
    sb.build();

    checkISE(() -> sb.accept(1));
    checkISE(() -> sb.add(1));
    checkISE(() -> sb.build());
}
 

@Test
public void testDoubleSingleton() {
    TestData.OfDouble data = TestData.Factory.ofDoubleSupplier("[0, 1)", () -> DoubleStream.of(1));

    withData(data).
            stream(s -> s).
            expectedResult(Collections.singletonList(1.0)).
            exercise();

    withData(data).
            stream(s -> s.map(i -> i)).
            expectedResult(Collections.singletonList(1.0)).
            exercise();
}
 

@Test(dataProvider = "DoubleStreamTestData", dataProviderClass = DoubleStreamTestDataProvider.class)
public void testOps(String name, TestData.OfDouble data) {
    AtomicLong expectedCount = new AtomicLong();
    data.stream().forEach(e -> expectedCount.incrementAndGet());

    withData(data).
            terminal(DoubleStream::count).
            expectedResult(expectedCount.get()).
            exercise();
}
 

private void testDoubleStreamBuilder(int size, Function<Integer, DoubleStream> supplier) {
    TestData.OfDouble data = TestData.Factory.ofDoubleSupplier(String.format("[0, %d)", size),
                                                               () -> supplier.apply(size));

    withData(data).
            stream(s -> s).
            expectedResult(IntStream.range(0, size).asDoubleStream().toArray()).
            exercise();

    withData(data).
            stream(s -> s.map(i -> i)).
            expectedResult(IntStream.range(0, size).asDoubleStream().toArray()).
            exercise();
}
 

/**
 * Constructs a time discretization using the given tick size.
 * The time discretization will be sorted. Duplicate entries are allowed if <code>allowDuplicates</code> is true, otherwise duplicate entries are removed.
 *
 * @param times A non closed and not necessarily sorted stream containing the time points.
 * @param tickSize A non-negative double representing the smallest time span distinguishable.
 * @param allowDuplicates If true, the time discretization allows duplicate entries.
 */
public TimeDiscretizationFromArray(DoubleStream times, final double tickSize, final boolean allowDuplicates) {
	timeTickSize = tickSize;
	times = times.map(this::roundToTimeTickSize);
	if(!allowDuplicates) {
		times = times.distinct();
	}
	timeDiscretization = times.sorted().toArray();
}
 

@Test(dataProvider = "StreamTestData<Integer>", dataProviderClass = StreamTestDataProvider.class)
public void testOps(String name, TestData.OfRef<Integer> data) {
    exerciseOpsInt(data,
                   s -> Stream.concat(s, data.stream()),
                   s -> IntStream.concat(s, data.stream().mapToInt(Integer::intValue)),
                   s -> LongStream.concat(s, data.stream().mapToLong(Integer::longValue)),
                   s -> DoubleStream.concat(s, data.stream().mapToDouble(Integer::doubleValue)));
}
 

private void testDoubleStreamBuilder(int size, Function<Integer, DoubleStream> supplier) {
    TestData.OfDouble data = TestData.Factory.ofDoubleSupplier(String.format("[0, %d)", size),
                                                               () -> supplier.apply(size));

    withData(data).
            stream(s -> s).
            expectedResult(IntStream.range(0, size).asDoubleStream().toArray()).
            exercise();

    withData(data).
            stream(s -> s.map(i -> i)).
            expectedResult(IntStream.range(0, size).asDoubleStream().toArray()).
            exercise();
}
 

@Test(dataProvider = "sizes")
public void testDoubleAfterBuilding(int size) {
    DoubleStream.Builder sb = DoubleStream.builder();
    IntStream.range(0, size).asDoubleStream().forEach(sb);
    sb.build();

    checkISE(() -> sb.accept(1));
    checkISE(() -> sb.add(1));
    checkISE(() -> sb.build());
}