@Test
public void evaluateDiscretize(){

	FieldName name = new FieldName("x");
	Discretize expression = new Discretize(name);
	assertEquals(null, evaluate(expression, createContext()));
	expression.setMapMissingTo("Missing");
	assertEquals("Missing", evaluate(expression, createContext()));
	assertEquals(null, evaluate(expression, createContext(name, 3)));
	expression.setDefaultValue("Default");
	assertEquals("Default", evaluate(expression, createContext(name, 3)));
}