### Question:
SumatraMath { public static boolean isEqual(final double a, final double b, final double tolerance) { return Math.abs(a - b) <= tolerance; } private  SumatraMath(); static double sqrt(final double number); static double square(final double x); static double min(final double... values); static double max(final double... values); static boolean hasDigitsAfterDecimalPoint(final double number); static boolean isEqual(final double a, final double b, final double tolerance); static boolean isEqual(final double a, final double b); static boolean isBetween(final double x, final double min, final double max); static boolean isZero(final double v); static double relative(final double value, final double from, final double to); static double cap(final double value, final double min, final double max); static List<Double> quadraticFunctionRoots(final double a, final double b, final double c); static List<Double> cubicFunctionRoots(final double a3, final double b2, final double c1, final double d0); static double getEqualTol(); static double acos(double x); static double asin(double x); static double atan2(double y, double x); static double cos(double angle); static double sin(double angle); static double tan(double angle); static List<Double> evenDistribution1D(double min, double max, int n);  }### Answer:
@Test public void testIsEqual() { Assertions.assertThat(SumatraMath.isEqual(1, 1)).isTrue(); Assertions.assertThat(SumatraMath.isEqual(1, 2)).isFalse(); Assertions.assertThat(SumatraMath.isEqual(1, 1, 0)).isTrue(); Assertions.assertThat(SumatraMath.isEqual(1, 2, 0)).isFalse(); Assertions.assertThat(SumatraMath.isEqual(1, 1.0001, 0)).isFalse(); Assertions.assertThat(SumatraMath.isEqual(1, 1.0001, 0.0001)).isTrue(); Assertions.assertThat(SumatraMath.isEqual(-1, -1, 0)).isTrue(); Assertions.assertThat(SumatraMath.isEqual(-1, -1.2, 1)).isTrue(); Assertions.assertThat(SumatraMath.isEqual(Double.POSITIVE_INFINITY, Double.POSITIVE_INFINITY, 0)).isFalse(); }