assertThat(oneValueAccumulator.mean()).isWithin(ALLOWED_ERROR).of(ONE_VALUE);
    assertThat(oneValueAccumulatorByAddAllEmptyStats.mean()).isWithin(ALLOWED_ERROR).of(ONE_VALUE);
    assertThat(twoValuesAccumulator.mean()).isWithin(ALLOWED_ERROR).of(TWO_VALUES_MEAN);
    assertThat(twoValuesAccumulatorByAddAllStats.mean())
        .isWithin(ALLOWED_ERROR)
        .of(TWO_VALUES_MEAN);

            .that(mean)
            .isWithin(ALLOWED_ERROR)
            .of(MANY_VALUES_MEAN);
      }
    }
    assertThat(MANY_VALUES_STATS_ITERABLE.mean()).isWithin(ALLOWED_ERROR).of(MANY_VALUES_MEAN);
    assertThat(MANY_VALUES_STATS_ITERATOR.mean()).isWithin(ALLOWED_ERROR).of(MANY_VALUES_MEAN);
    assertThat(MANY_VALUES_STATS_SNAPSHOT.mean()).isWithin(ALLOWED_ERROR).of(MANY_VALUES_MEAN);

        .isWithin(ALLOWED_ERROR)
        .of(MANY_VALUES_SUM_OF_PRODUCTS_OF_DELTAS / (MANY_VALUES_COUNT - 1));
    assertThat(HORIZONTAL_VALUES_PAIRED_STATS.sampleCovariance()).isWithin(ALLOWED_ERROR).of(0.0);
    assertThat(VERTICAL_VALUES_PAIRED_STATS.sampleCovariance()).isWithin(ALLOWED_ERROR).of(0.0);
    assertThat(CONSTANT_VALUES_PAIRED_STATS.sampleCovariance()).isWithin(ALLOWED_ERROR).of(0.0);
  }

        .isWithin(ALLOWED_ERROR)
        .of(MANY_VALUES_SUM_OF_PRODUCTS_OF_DELTAS / (MANY_VALUES_COUNT - 1));
    assertThat(HORIZONTAL_VALUES_PAIRED_STATS.sampleCovariance()).isWithin(ALLOWED_ERROR).of(0.0);
    assertThat(VERTICAL_VALUES_PAIRED_STATS.sampleCovariance()).isWithin(ALLOWED_ERROR).of(0.0);
    assertThat(CONSTANT_VALUES_PAIRED_STATS.sampleCovariance()).isWithin(ALLOWED_ERROR).of(0.0);
  }

    assertThat(oneValueAccumulator.mean()).isWithin(ALLOWED_ERROR).of(ONE_VALUE);
    assertThat(oneValueAccumulatorByAddAllEmptyStats.mean()).isWithin(ALLOWED_ERROR).of(ONE_VALUE);
    assertThat(twoValuesAccumulator.mean()).isWithin(ALLOWED_ERROR).of(TWO_VALUES_MEAN);
    assertThat(twoValuesAccumulatorByAddAllStats.mean())
        .isWithin(ALLOWED_ERROR)
        .of(TWO_VALUES_MEAN);

import junit.framework.TestCase;

/**
 * Tests for {@link LinearTransformation}.
 *
 * @author Pete Gillin
 */
public class LinearTransformationTest extends TestCase {

  private static final double ALLOWED_ERROR = 1e-10;

  public void testMappingAnd_regular() {
    double x1 = 1.2;
    double y1 = 3.4;
    double xDelta = 5.6;
    double yDelta = 7.8;
    LinearTransformation transformation =

import junit.framework.TestCase;

/**
 * Tests for {@link LinearTransformation}.
 *
 * @author Pete Gillin
 */
public class LinearTransformationTest extends TestCase {

  private static final double ALLOWED_ERROR = 1e-10;

  public void testMappingAnd_regular() {
    double x1 = 1.2;
    double y1 = 3.4;
    double xDelta = 5.6;
    double yDelta = 7.8;
    LinearTransformation transformation =

            .that(mean)
            .isWithin(ALLOWED_ERROR)
            .of(MANY_VALUES_MEAN);
      }
    }
    assertThat(MANY_VALUES_STATS_ITERABLE.mean()).isWithin(ALLOWED_ERROR).of(MANY_VALUES_MEAN);
    assertThat(MANY_VALUES_STATS_ITERATOR.mean()).isWithin(ALLOWED_ERROR).of(MANY_VALUES_MEAN);
    assertThat(MANY_VALUES_STATS_SNAPSHOT.mean()).isWithin(ALLOWED_ERROR).of(MANY_VALUES_MEAN);

  public void testReplaceEntry_absentKeyNullValueUnsupported() {
    try {
      assertFalse(getMap().replace(k3(), v3(), null));
    } catch (NullPointerException tolerated) {
      // the operation would be a no-op, so exceptions are allowed but not required
    }
    expectUnchanged();
  }

  @MapFeature.Require({SUPPORTS_PUT, ALLOWS_NULL_VALUE_QUERIES})

      assertThat(actualStats.mean()).isWithin(ALLOWED_ERROR).of(expectedStats.mean());
      assertThat(actualStats.populationVariance()).isWithin(0.0).of(0.0);
      assertThat(actualStats.min()).isWithin(ALLOWED_ERROR).of(expectedStats.min());
      assertThat(actualStats.max()).isWithin(ALLOWED_ERROR).of(expectedStats.max());
    } else {
      assertThat(actualStats.mean()).isWithin(ALLOWED_ERROR).of(expectedStats.mean());