Wsrtjtyk

As according to this stack question: How to calculate the rolling average of a C# array list?

With a normal list you can take a running average of values in the list like this:

List<int> numlist = new List<int>();

List<double> averages = Enumerable.Range(0, numlist.Count - 3).

                          Select(i => numlist.Skip(i).Take(4).Average()).

                          ToList();

I want to do the same, however on a specific subset of a class list:

public class Data_Raw

{

    public DateTime DateDataRaw { set; get; }

    public double PriceRaw { set; get; }

    public double PercentageReturnsRaw { set; get; }



    public Data_Raw(DateTime _dateDataRaw,double _priceRaw, double _percentageReturnsRaw)

    {

        DateDataRaw = _dateDataRaw;                     //1

        PriceRaw = _priceRaw;

        PercentageReturnsRaw = _percentageReturnsRaw;

    }

}



List<Data_Raw> myRawData = new List<Data_Raw>();

So now I want to get the average, for instance of the PriceRaw double data, within the class list which is myRawData. Please help

EDIT:

If these are the data for the PriceRaw variable of the myRawData list:

myRawData[0].PriceRaw=2

myRawData[1].PriceRaw=3

myRawData[2].PriceRaw=4

myRawData[3].PriceRaw=5

How do I get the average value of the last three PriceRaw values which is = (3+4+5)/3 = 4. It is only available directly after myRawData.Skip

Skip is not available if I try to append it to myRawData.PriceRaw.Skip

This stack question gets me closer, but can't figure it out: Linq query a List of objects containing a list of object

Simply select the value you need into your numList (see first line):

var numList = myRawData.Select(x => x.PriceRaw).ToList();

List<double> averages = Enumerable.Range(0, numlist.Count - 3).

                      Select(i => numlist.Skip(i).Take(4).Average()).

                      ToList();

An alternate way could be this:

List<double> averages = Enumerable.Range(0, myRawData.Count - 3).

                      Select(i => myRawData.Skip(i).Take(4).Select(x => x.PriceRaw).Average()).

                      ToList();

I think it would be easier for you to manage it if you use comprehension syntax. ie:

void Main()

{

    List<Data_Raw> myRawData = new List<Data_Raw> {

       new Data_Raw(new DateTime(2018,1,1), 2, 1),

       new Data_Raw(new DateTime(2018,1,2), 3, 1),

       new Data_Raw(new DateTime(2018,1,3), 4, 1),

       new Data_Raw(new DateTime(2018,1,4), 5, 1),

       new Data_Raw(new DateTime(2018,1,5), 6, 1),

       new Data_Raw(new DateTime(2018,1,6), 7, 1),

       new Data_Raw(new DateTime(2018,1,7), 8, 1),

    };



    var groupSize = 3;

    var result = from i in Enumerable.Range(0, myRawData.Count() - (groupSize - 1))

                 let myGroup = myRawData.Skip(i).Take(groupSize)

                 select new

                 {

                     Values = string.Join(",", myGroup.Select(rd => rd.PriceRaw.ToString())),

                     Average = myGroup.Average(rd => rd.PriceRaw)

                 };

}



public class Data_Raw

{

    public DateTime DateDataRaw { set; get; }

    public double PriceRaw { set; get; }

    public double PercentageReturnsRaw { set; get; }



    public Data_Raw(DateTime _dateDataRaw, double _priceRaw, double _percentageReturnsRaw)

    {

        DateDataRaw = _dateDataRaw;                     //1

        PriceRaw = _priceRaw;

        PercentageReturnsRaw = _percentageReturnsRaw;

    }

}