* implementations.
   *
   * @throws IllegalArgumentException if {@code tolerance} is {@code < 0} or NaN
   * @since 13.0
   */
  public static boolean fuzzyEquals(double a, double b, double tolerance) {
    MathPreconditions.checkNonNegative("tolerance", tolerance);
    return Math.copySign(a - b, 1.0) <= tolerance

        assertTrue(DoubleMath.fuzzyEquals(inf, inf, tolerance));
        assertFalse(DoubleMath.fuzzyEquals(inf, -inf, tolerance));
      }
    }
  }

  public void testFuzzyEqualsInfiniteTolerance() {
    for (double a : DOUBLE_CANDIDATES_EXCEPT_NAN) {
      for (double b : DOUBLE_CANDIDATES_EXCEPT_NAN) {
        assertTrue(DoubleMath.fuzzyEquals(a, b, Double.POSITIVE_INFINITY));
      }
    }
  }