test/java/util/stream/TestDoubleSumAverage.java
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*** 23,50 ****
import java.util.*;
import java.util.function.*;
import java.util.stream.*;
/*
* @test
! * @bug 8006572
* @summary Test for use of non-naive summation in stream-related sum and average operations.
*/
public class TestDoubleSumAverage {
public static void main(String... args) {
int failures = 0;
- failures += testForCompenstation();
failures += testZeroAverageOfNonEmptyStream();
if (failures > 0) {
throw new RuntimeException("Found " + failures + " numerical failure(s).");
}
}
/**
* 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 testForCompenstation() {
int failures = 0;
--- 23,62 ----
import java.util.*;
import java.util.function.*;
import java.util.stream.*;
+ import static java.lang.Double.*;
+
/*
* @test
! * @bug 8006572 8030212
* @summary Test for use of non-naive summation in stream-related sum and average operations.
*/
public class TestDoubleSumAverage {
public static void main(String... args) {
int failures = 0;
failures += testZeroAverageOfNonEmptyStream();
+ failures += testForCompenstation();
+ failures += testNonfiniteSum();
if (failures > 0) {
throw new RuntimeException("Found " + failures + " numerical failure(s).");
}
}
/**
+ * Test to verify that a non-empty stream with a zero average is non-empty.
+ */
+ private static int testZeroAverageOfNonEmptyStream() {
+ Supplier<DoubleStream> ds = () -> DoubleStream.iterate(0.0, e -> 0.0).limit(10);
+
+ return compareUlpDifference(0.0, ds.get().average().getAsDouble(), 0);
+ }
+
+ /**
* 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 testForCompenstation() {
int failures = 0;
*** 81,103 ****
failures += compareUlpDifference(expectedAvg,
ds.get().boxed().collect(Collectors.averagingDouble(d -> d)),3);
return failures;
}
! /**
! * Test to verify that a non-empty stream with a zero average is non-empty.
! */
! private static int testZeroAverageOfNonEmptyStream() {
! Supplier<DoubleStream> ds = () -> DoubleStream.iterate(0.0, e -> 0.0).limit(10);
! return compareUlpDifference(0.0, ds.get().average().getAsDouble(), 0);
}
/**
* Compute the ulp difference of two double values and compare against an error threshold.
*/
private static int compareUlpDifference(double expected, double computed, double threshold) {
double ulpDifference = Math.abs(expected - computed) / Math.ulp(expected);
if (ulpDifference > threshold) {
System.err.printf("Numerical summation error too large, %g ulps rather than %g.%n",
ulpDifference, threshold);
--- 93,164 ----
failures += compareUlpDifference(expectedAvg,
ds.get().boxed().collect(Collectors.averagingDouble(d -> d)),3);
return failures;
}
! private static int testNonfiniteSum() {
! int failures = 0;
! Map<Supplier<DoubleStream>, Double> testCases = new LinkedHashMap<>();
! testCases.put(() -> DoubleStream.of(MAX_VALUE, MAX_VALUE), POSITIVE_INFINITY);
! testCases.put(() -> DoubleStream.of(-MAX_VALUE, -MAX_VALUE), NEGATIVE_INFINITY);
!
! testCases.put(() -> DoubleStream.of(1.0d, POSITIVE_INFINITY, 1.0d), POSITIVE_INFINITY);
! testCases.put(() -> DoubleStream.of(POSITIVE_INFINITY), POSITIVE_INFINITY);
! testCases.put(() -> DoubleStream.of(POSITIVE_INFINITY, POSITIVE_INFINITY), POSITIVE_INFINITY);
! testCases.put(() -> DoubleStream.of(POSITIVE_INFINITY, POSITIVE_INFINITY, 0.0), POSITIVE_INFINITY);
!
! testCases.put(() -> DoubleStream.of(1.0d, NEGATIVE_INFINITY, 1.0d), NEGATIVE_INFINITY);
! testCases.put(() -> DoubleStream.of(NEGATIVE_INFINITY), NEGATIVE_INFINITY);
! testCases.put(() -> DoubleStream.of(NEGATIVE_INFINITY, NEGATIVE_INFINITY), NEGATIVE_INFINITY);
! testCases.put(() -> DoubleStream.of(NEGATIVE_INFINITY, NEGATIVE_INFINITY, 0.0), NEGATIVE_INFINITY);
!
! testCases.put(() -> DoubleStream.of(1.0d, NaN, 1.0d), NaN);
! testCases.put(() -> DoubleStream.of(NaN), NaN);
! testCases.put(() -> DoubleStream.of(1.0d, NEGATIVE_INFINITY, POSITIVE_INFINITY, 1.0d), NaN);
! testCases.put(() -> DoubleStream.of(1.0d, POSITIVE_INFINITY, NEGATIVE_INFINITY, 1.0d), NaN);
! testCases.put(() -> DoubleStream.of(POSITIVE_INFINITY, NaN), NaN);
! testCases.put(() -> DoubleStream.of(NEGATIVE_INFINITY, NaN), NaN);
! testCases.put(() -> DoubleStream.of(NaN, POSITIVE_INFINITY), NaN);
! testCases.put(() -> DoubleStream.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(DoubleSummaryStatistics::new,
! DoubleSummaryStatistics::accept,
! DoubleSummaryStatistics::combine);
!
! 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(d -> d)), 0);
! failures += compareUlpDifference(expected, ds.get().boxed().collect(Collectors.averagingDouble(d -> d)), 0);
! }
!
! return failures;
}
/**
* Compute the ulp difference of two double values and compare against an error threshold.
*/
private static int compareUlpDifference(double expected, double computed, double threshold) {
+ if (!Double.isFinite(expected)) {
+ // Handle NaN and infinity cases
+ if (Double.compare(expected, computed) == 0)
+ return 0;
+ else {
+ System.err.printf("Unexpected sum, %g rather than %g.%n",
+ computed, expected);
+ return 1;
+ }
+ }
+
double ulpDifference = Math.abs(expected - computed) / Math.ulp(expected);
if (ulpDifference > threshold) {
System.err.printf("Numerical summation error too large, %g ulps rather than %g.%n",
ulpDifference, threshold);