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Example 1 with ObjDoubleConsumer

use of java8.util.function.ObjDoubleConsumer in project streamsupport by stefan-zobel.

the class TestDoubleSumAverage method testForCompensation.

/**
 * Compute the sum and average of a sequence of double values in
 * various ways and report an error if naive summation is used.
 */
private static int testForCompensation() {
    int failures = 0;
    /*
         * The exact sum of the test stream is 1 + 1e6*ulp(1.0) but a
         * naive summation algorithm will return 1.0 since (1.0 +
         * ulp(1.0)/2) will round to 1.0 again.
         */
    final double base = 1.0;
    final double increment = Math.ulp(base) / 2.0;
    final int count = 1000001;
    double expectedSum = base + (increment * (count - 1));
    double expectedAvg = expectedSum / count;
    // Factory for double a stream of [base, increment, ..., increment] limited to a size of count
    Supplier<DoubleStream> ds = new Supplier<DoubleStream>() {

        @Override
        public DoubleStream get() {
            return DoubleStreams.iterate(base, new DoubleUnaryOperator() {

                @Override
                public double applyAsDouble(double e) {
                    return increment;
                }
            }).limit(count);
        }
    };
    DoubleSummaryStatistics stats = ds.get().collect(new Supplier<DoubleSummaryStatistics>() {

        @Override
        public DoubleSummaryStatistics get() {
            return new DoubleSummaryStatistics();
        }
    }, (ObjDoubleConsumer<DoubleSummaryStatistics>) new ObjDoubleConsumer<DoubleSummaryStatistics>() {

        @Override
        public void accept(DoubleSummaryStatistics doubleSummaryStatistics, double v) {
            doubleSummaryStatistics.accept(v);
        }
    }, (BiConsumer<DoubleSummaryStatistics, DoubleSummaryStatistics>) new BiConsumer<DoubleSummaryStatistics, DoubleSummaryStatistics>() {

        @Override
        public void accept(DoubleSummaryStatistics doubleSummaryStatistics, DoubleSummaryStatistics doubleSummaryStatistics2) {
            doubleSummaryStatistics.combine(doubleSummaryStatistics2);
        }
    });
    failures += compareUlpDifference(expectedSum, stats.getSum(), 3);
    failures += compareUlpDifference(expectedAvg, stats.getAverage(), 3);
    failures += compareUlpDifference(expectedSum, ds.get().sum(), 3);
    failures += compareUlpDifference(expectedAvg, ds.get().average().getAsDouble(), 3);
    failures += compareUlpDifference(expectedSum, ds.get().boxed().collect(Collectors.summingDouble(new ToDoubleFunction<Double>() {

        @Override
        public double applyAsDouble(Double d) {
            return d;
        }
    })), 3);
    failures += compareUlpDifference(expectedAvg, ds.get().boxed().collect(Collectors.averagingDouble(new ToDoubleFunction<Double>() {

        @Override
        public double applyAsDouble(Double d) {
            return d;
        }
    })), 3);
    return failures;
}
Also used : DoubleSummaryStatistics(java8.util.DoubleSummaryStatistics) Double(java.lang.Double)

Example 2 with ObjDoubleConsumer

use of java8.util.function.ObjDoubleConsumer in project streamsupport by stefan-zobel.

the class TestDoubleSumAverage method testNonfiniteSum.

private static int testNonfiniteSum() {
    int failures = 0;
    Map<Supplier<DoubleStream>, Double> testCases = new LinkedHashMap<Supplier<DoubleStream>, Double>();
    testCases.put(new Supplier<DoubleStream>() {

        @Override
        public DoubleStream get() {
            return DoubleStreams.of(MAX_VALUE, MAX_VALUE);
        }
    }, POSITIVE_INFINITY);
    testCases.put(new Supplier<DoubleStream>() {

        @Override
        public DoubleStream get() {
            return DoubleStreams.of(-MAX_VALUE, -MAX_VALUE);
        }
    }, NEGATIVE_INFINITY);
    testCases.put(new Supplier<DoubleStream>() {

        @Override
        public DoubleStream get() {
            return DoubleStreams.of(1.0d, POSITIVE_INFINITY, 1.0d);
        }
    }, POSITIVE_INFINITY);
    testCases.put(new Supplier<DoubleStream>() {

        @Override
        public DoubleStream get() {
            return DoubleStreams.of(POSITIVE_INFINITY);
        }
    }, POSITIVE_INFINITY);
    testCases.put(new Supplier<DoubleStream>() {

        @Override
        public DoubleStream get() {
            return DoubleStreams.of(POSITIVE_INFINITY, POSITIVE_INFINITY);
        }
    }, POSITIVE_INFINITY);
    testCases.put(new Supplier<DoubleStream>() {

        @Override
        public DoubleStream get() {
            return DoubleStreams.of(POSITIVE_INFINITY, POSITIVE_INFINITY, 0.0);
        }
    }, POSITIVE_INFINITY);
    testCases.put(new Supplier<DoubleStream>() {

        @Override
        public DoubleStream get() {
            return DoubleStreams.of(1.0d, NEGATIVE_INFINITY, 1.0d);
        }
    }, NEGATIVE_INFINITY);
    testCases.put(new Supplier<DoubleStream>() {

        @Override
        public DoubleStream get() {
            return DoubleStreams.of(NEGATIVE_INFINITY);
        }
    }, NEGATIVE_INFINITY);
    testCases.put(new Supplier<DoubleStream>() {

        @Override
        public DoubleStream get() {
            return DoubleStreams.of(NEGATIVE_INFINITY, NEGATIVE_INFINITY);
        }
    }, NEGATIVE_INFINITY);
    testCases.put(new Supplier<DoubleStream>() {

        @Override
        public DoubleStream get() {
            return DoubleStreams.of(NEGATIVE_INFINITY, NEGATIVE_INFINITY, 0.0);
        }
    }, NEGATIVE_INFINITY);
    testCases.put(new Supplier<DoubleStream>() {

        @Override
        public DoubleStream get() {
            return DoubleStreams.of(1.0d, NaN, 1.0d);
        }
    }, NaN);
    testCases.put(new Supplier<DoubleStream>() {

        @Override
        public DoubleStream get() {
            return DoubleStreams.of(NaN);
        }
    }, NaN);
    testCases.put(new Supplier<DoubleStream>() {

        @Override
        public DoubleStream get() {
            return DoubleStreams.of(1.0d, NEGATIVE_INFINITY, POSITIVE_INFINITY, 1.0d);
        }
    }, NaN);
    testCases.put(new Supplier<DoubleStream>() {

        @Override
        public DoubleStream get() {
            return DoubleStreams.of(1.0d, POSITIVE_INFINITY, NEGATIVE_INFINITY, 1.0d);
        }
    }, NaN);
    testCases.put(new Supplier<DoubleStream>() {

        @Override
        public DoubleStream get() {
            return DoubleStreams.of(POSITIVE_INFINITY, NaN);
        }
    }, NaN);
    testCases.put(new Supplier<DoubleStream>() {

        @Override
        public DoubleStream get() {
            return DoubleStreams.of(NEGATIVE_INFINITY, NaN);
        }
    }, NaN);
    testCases.put(new Supplier<DoubleStream>() {

        @Override
        public DoubleStream get() {
            return DoubleStreams.of(NaN, POSITIVE_INFINITY);
        }
    }, NaN);
    testCases.put(new Supplier<DoubleStream>() {

        @Override
        public DoubleStream get() {
            return DoubleStreams.of(NaN, NEGATIVE_INFINITY);
        }
    }, NaN);
    for (Map.Entry<Supplier<DoubleStream>, Double> testCase : testCases.entrySet()) {
        Supplier<DoubleStream> ds = testCase.getKey();
        double expected = testCase.getValue();
        DoubleSummaryStatistics stats = ds.get().collect(new Supplier<DoubleSummaryStatistics>() {

            @Override
            public DoubleSummaryStatistics get() {
                return new DoubleSummaryStatistics();
            }
        }, (ObjDoubleConsumer<DoubleSummaryStatistics>) new ObjDoubleConsumer<DoubleSummaryStatistics>() {

            @Override
            public void accept(DoubleSummaryStatistics doubleSummaryStatistics, double v) {
                doubleSummaryStatistics.accept(v);
            }
        }, (BiConsumer<DoubleSummaryStatistics, DoubleSummaryStatistics>) new BiConsumer<DoubleSummaryStatistics, DoubleSummaryStatistics>() {

            @Override
            public void accept(DoubleSummaryStatistics doubleSummaryStatistics, DoubleSummaryStatistics doubleSummaryStatistics2) {
                doubleSummaryStatistics.combine(doubleSummaryStatistics2);
            }
        });
        failures += compareUlpDifference(expected, stats.getSum(), 0);
        failures += compareUlpDifference(expected, stats.getAverage(), 0);
        failures += compareUlpDifference(expected, ds.get().sum(), 0);
        failures += compareUlpDifference(expected, ds.get().average().getAsDouble(), 0);
        failures += compareUlpDifference(expected, ds.get().boxed().collect(Collectors.summingDouble(new ToDoubleFunction<Double>() {

            @Override
            public double applyAsDouble(Double d) {
                return d;
            }
        })), 0);
        failures += compareUlpDifference(expected, ds.get().boxed().collect(Collectors.averagingDouble(new ToDoubleFunction<Double>() {

            @Override
            public double applyAsDouble(Double d) {
                return d;
            }
        })), 0);
    }
    return failures;
}
Also used : DoubleSummaryStatistics(java8.util.DoubleSummaryStatistics) Double(java.lang.Double)

Aggregations

Double (java.lang.Double)2 DoubleSummaryStatistics (java8.util.DoubleSummaryStatistics)2