System.Linq.Tests.AverageTests.NullableDoubleFromSelector C# (CSharp) Method

        public void NullableDoubleFromSelector()
        {
            var source = new[]
            {
                new{ name = "Tim", num = (double?)5.5 },
                new{ name = "John", num = (double?)15.5 },
                new{ name = "Bob", num = default(double?) }
            };
            double? expected = 10.5;

            Assert.Equal(expected, source.AsQueryable().Average(e => e.num));
        }