Excel vba nested dictionary - accessing items - excel

Question

Tim is it possible to extract a list of row keys from the clsMatrix class? something like this...
Sub KEYS()
Dim KEY_LIST As Variant
KEY_LIST = TABLES("UDLY").dR.KEYS
End Sub
I can then cycle through a table to extract a subset of data which meet a certain criteria.
Tim, your code works well for one 2D matrix, but I have 5 tables to reference for the project to work. I tried using if...then else statements, but it's clumsy and doesn't work - the second pass looking for data from the BOOK table can't find the row and col dictionary references. Can you suggest a better method? Thanks for your help.
Option Explicit
Private dR, dC
Private m_arr, UDLY, BOOK
'
Sub Init(TABLE As String)
Dim i As Long
Dim RNGE As Range
Dim DATA As Variant
Dim arr As Variant
If TABLE = "UDLY" Then Set RNGE = Worksheets("SETTINGS").Range("UDLY_TABLE")
If TABLE = "BOOK" Then Set RNGE = Worksheets("BOOK").Range("BOOK_TABLE")
arr = RNGE.Value
Set dR = CreateObject("Scripting.Dictionary")
Set dC = CreateObject("Scripting.Dictionary")
'add the row keys and positions
For i = LBound(arr, 1) + 1 To UBound(arr, 1)
dR.Add arr(i, 1), i
Next i
'add the column keys and positions
For i = LBound(arr, 2) + 1 To UBound(arr, 2)
dC.Add arr(1, i), i
Next i
' m_arr = arr
If TABLE = "UDLY" Then UDLY = arr
If TABLE = "BOOK" Then BOOK = arr
End Sub
Function GetValue(TABLE, rowKey, colKey)
If dR.Exists(rowKey) And dC.Exists(colKey) Then
' GetValue = m_arr(dR(rowKey), dC(colKey))
If TABLE = "UDLY" Then GetValue = UDLY(dR(rowKey), dC(colKey))
If TABLE = "BOOK" Then GetValue = BOOK(dR(rowKey), dC(colKey))
Else
GetValue = 999 '"" 'or raise an error...
End If
End Function
'===========================================================
Option Explicit
Sub Tester()
Dim m As New clsMatrix
' m.Init (ActiveSheet.Range("b40").CurrentRegion.Value)
' m.Init (Worksheets("settings").Range("udly_table"))
m.Init ("UDLY")
Debug.Print m.GetValue("UDLY", "APZ4-FUT", "SPOT_OFFLINE")
m.Init ("BOOK")
Debug.Print m.GetValue("BOOK", "2.04", "STRIKE")
End Sub

Answer 1

Sub DICT_OF_DICT()
Dim d1, d2
Set d1 = CreateObject("Scripting.Dictionary")
Set d2 = CreateObject("Scripting.Dictionary")
d1.Add "BPH", "Hello"
d2.Add "Shaun", d1
Debug.Print d2("Shaun").Item("BPH")
End Sub
EDIT: if I wanted to deal with quickly accessing a 2-D array using row/column headers then I'd be inclined not to use nested dictionaries, but to use two distinct dictionaries to key into each dimension (a "row label" dictionary and a "column label" one).
You can wrap this up in a simple class:
'Class module: clsMatrix
Option Explicit
Private dR, dC
Private m_arr
Sub Init(arr)
Dim i As Long
Set dR = CreateObject("Scripting.Dictionary")
Set dC = CreateObject("Scripting.Dictionary")
'add the row keys and positions
For i = LBound(arr, 1) + 1 To UBound(arr, 1)
dR.Add arr(i, 1), i
Next i
'add the column keys and positions
For i = LBound(arr, 2) + 1 To UBound(arr, 2)
dC.Add arr(1, i), i
Next i
m_arr = arr
End Sub
Function GetValue(rowKey, colKey)
If dR.Exists(rowKey) And dC.Exists(colKey) Then
GetValue = m_arr(dR(rowKey), dC(colKey))
Else
GetValue = "" 'or raise an error...
End If
End Function
'EDIT: added functions to return row/column keys
' return a zero-based array
Function RowKeys()
RowKeys = dR.Keys
End Function
Function ColumnKeys()
ColumnKeys = dC.Keys
End Function
Example usage: assuming A1 is the top-left cell in a rectangular range where the first row is column headers ("col1" to "colx") and the first column is row headers ("row1" to "rowy") -
EDIT2: made some changes to show how to manage multiple different tables (with no changes to the class code)
'Regular module
Sub Tester()
Dim tables As Object, k
Set tables = CreateObject("Scripting.Dictionary")
tables.Add "Table1", New clsMatrix
tables("Table1").Init ActiveSheet.Range("A1").CurrentRegion.Value
tables.Add "Table2", New clsMatrix
tables("Table2").Init ActiveSheet.Range("H1").CurrentRegion.Value
Debug.Print tables("Table1").GetValue("Row1", "Col3")
Debug.Print tables("Table2").GetValue("R1", "C3")
k = tables("Table1").RowKeys()
Debug.Print Join(k, ", ")
End Sub