public async Task Evaluate_3V1L_Theory(double one, double two, double three, double expected) { var op = new Subtract() { Variables = new List <Variable>() { one, two, three } }; var subProvider = new DictionarySubstitutionProvider(new Dictionary <string, double>() { { "__unspecified__", 1 } }); var result = await op.Evaluate(subProvider); Assert.Equal(expected, result); }