public void testGetApproximateMinimumInterval() {
MockXYDataset mxy = new MockXYDataset();
assertTrue("Approximate minimum interval should be atleast less than twice as big as first two datapoints in Mock dataset",
mxy.getApproximateMinimumInterval() <= 2 * (mxy.getX(1) - mxy.getX(0)));
XYDataset xy = Fixtures.getPositiveDomainDescendingRange();
assertTrue("Approximate minimum interval should be atleast less than twice as big as first two datapoints in Fixture dataset",
xy.getApproximateMinimumInterval() <= 2 * (xy.getX(1) - mxy.getX(0)));
}