// Type: float?, selector function is called public static int Test11g() { Data_Nfloat[] source = new Data_Nfloat[]{ new Data_Nfloat{name="Tim", num=40.5f}, new Data_Nfloat{name="John", num=null}, new Data_Nfloat{name="Bob", num=100.45f} }; float? expected = 100.45f; var actual = source.Max((e) => e.num); return ((expected == actual) ? 0 : 1); }