Linq Group by Sum Lists Elementwise - vb.net

Question

The list of doubles SC is of same size for all of CTable.
I would like add SC grouped by CTable.Ch. The result should be a List of sums. Is there an operator/customization for that?
Public Class SCRow
Public L As String
Public Ch As String
Public SC As List(Of Double)
End Class
Dim CTable AS New List(Of SCRow)
Dim AggrC =
From C In CTable
Group C By Key = C.Ch
Into Group
Select New With
{
.Ch= Key,
.SumSC = Group.Sum(Function(x) ???)
}
Example:
CTable.Add(New SCRow With {.L = "L1", .Ch = "Ch1", .SC = New List(Of Double)(New Double() {1.0, 2.0})})
CTable.Add(New SCRow With {.L = "L1", .Ch = "Ch2", .SC = New List(Of Double)(New Double() {3.0, 4.0})})
CTable.Add(New SCRow With {.L = "L2", .Ch = "Ch1", .SC = New List(Of Double)(New Double() {5.0, 6.0})})
Output:
Ch1 {6=1+5, 8=2+6}
Ch2 {3, 4}

Answer 1

It can be done using Aggregate extension method along with Zip method. I have written the code in C#. Please translate it to VB.Net. Hope it will help.
Aggregate: Performs a specified operation to each element in a collection, while carrying the result forward.
Zip: The Zip extension method acts upon two collections. It processes each element in two series together.
public class SCRow
{
public string L { get; set; }
public string CH { get; set; }
public List<double> SC { get; set; }
}
class Program
{
static void Main(string[] args)
{
var CTable = new List<SCRow>{
new SCRow { L = "L1", CH = "Ch1", SC = new List<double> { 1.0, 2.0}},
new SCRow { L = "L1", CH = "Ch2", SC = new List<double> { 3.0, 4.0}},
new SCRow { L = "L2", CH = "Ch1", SC = new List<double> { 5.0, 6.0}},
};
var result = CTable.GroupBy(c => c.CH)
.Select(x => new
{
Value = x.Aggregate((curr, next) => new SCRow
{
CH = x.Key,
SC = curr.SC.Zip(next.SC, (n1, n2) => n1 + n2).ToList()
})
})
.Select(y => new {
CH = y.Value.CH,
ScSum = y.Value.SC
}).ToList();
}
}