data range transformation - vba

Question

I have a list of objects that is being returned from service call.
Object has below attributes:
DateVal1
DateVal2
Value
How do I assign object to range as 2D matrix range:
Date1 as column, Date2 as header row
If there is object with row,column combination print value else print NA.
Data can be large (Max 30x30) so trying to avoid lookup in list every time.
Date 1/31/2015 2/28/2015 3/31/2015
1/1/2015 1 NA NA
1/2/2015 NA 2 NA
1/3/2015 NA NA 3
What if this is slight different?
Object has below attributes:
DateVal1
DateVal2
Value1
Value2
And desired o/p is this:
Date1 Date2 110 20 30
1/1/2015 1/10/2015 1 NA NA
1/2/2015 1/20/2015 NA 2 NA
1/3/2015 1/31/2015 NA NA 3

Answer 1

Untested, but something like this:
Sub Test()
Dim points, i As Long, r As Long, c As Long
Dim dictRows, dictCols, grid(0, 0)
'dictionary to map "key" values to row numbers
Set dictRows = CreateObject("scripting.dictionary")
'dictionary to map "key" values to column numbers
Set dictCols = CreateObject("scripting.dictionary")
points = getPoints()
r = 0
c = 0
'[sort points by date1 here]
'map date1 to "row"
For i = LBound(points) To UBound(points)
If Not dictRows.exists(points(i).date1) Then
r = r + 1
dictRows.Add points(i).date1, r
End If
Next i
'[sort points by date2 here]
'map date2 to "column"
For i = LBound(points) To UBound(points)
If Not dictCols.exists(points(i).date2) Then
c = c + 1
dictCols.Add points(i).date2, c
End If
Next i
ReDim grid(1 To r, 1 To c)
For i = LBound(points) To UBound(points)
grid(dictRows(points(i).date1), dictCols(points(i).date2)) = points(i).Value
Next i
'populate on worksheet
With ActiveSheet
.Range("A2").Resize(r, 1).Value = Application.Transpose(dictRows.keys)
.Range("B2").Resize(r, c).Value = grid
.Range("B1").Resize(1, c).Value = dictCols.keys
End With
End Sub