Summing records in VBA Collection - linq

Question

I have a VBA collection consisting of DayTots class objects (see below)
I am using a For Each to iterate thru the collection to create a
new collection consisting of summed records, based on Date
Is there some way I could do this with Linq? I suspect maybe I could replace
several lines of code with something much simpler and more straightforward
using a Linq query (maybe using a Group?)
I couldn't find anything on the internet that seemed to address this situation
Thanks in advance for all assistance
input collection
tDate TotTrav TotTrav TotParts
Yes No Accepted
2/27/2017 1 0 1
2/27/2017 1 0 0
2/27/2017 1 0 0
2/27/2017 0 1 0
2/28/2017 1 0 1
2/28/2017 0 1 0
2/28/2017 0 0 1
output collection
DatDate TotTrav TotTrav TotParts
Yes No Accepted
2/27/2017 3 1 1
2/28/2017 1 1 2
Dim cumRecs As DayTots
dim incoll, outcoll as Collection
outcoll = New Collection
For Each irec In incoll
....
outcoll.Add(cumRecs)
Next irec
'Class DayTots
Dim DatDate As Date
Dim TravYes As Integer
Dim TravNo As Integer
Dim PartsAccepted As Integer
Public Property Get tDayDate() As Date
tDayDate = DatDate
End Property
Public Property Let tDayDate(value As Date)
DatDate = value
Weekno = Int(((DatDate - DateSerial(Year(DatDate), 1, 0)) + 6) / 7)
End Property
Public Property Get TotTravYes() As Integer
TotTravYes = TravYes
End Property
Public Property Let TotTravYes(value As Integer)
TravYes = value
End Property
Public Property Get TotTravNo() As Integer
TotTravNo = TravNo
End Property
Public Property Let TotTravNo(value As Integer)
TravNo = value
End Property
Public Property Get TotPartsAccepted() As Integer
TotPartsAccepted = PartsAccepted
End Property
Public Property Let TotPartsAccepted(value As Integer)
PartsAccepted = value
End Property

Answer 1

What you are hoping for can be achieved with Array and WorksheetFunction.Sum Here is a small example:
Option Explicit
Public Sub TestMe()
Dim inColl As New Collection
Dim inArr As Variant
inColl.Add 1
inColl.Add 2
inColl.Add 3
Debug.Print WorksheetFunction.Sum(inColl.Item(1), inColl.Item(2), inColl.Item(3))
inArr = Array(5, 6, 7, 8)
Debug.Print WorksheetFunction.Sum(inArr)
End Sub
The result in the immediate window is 6 and 26. In general, it is not difficult to convert collection to array.