stephenc said:
I need to copy the content of a 2D array to another identical 2D array. I
currently do it this way...
for X=1 to 1000
for Y = 1 to 1000
A(X,Y) = B(X,Y)
next Y
next X
Is there a better/quicker way to do it?
There are quicker ways, yes. But I'd be hard pressed to say they're
"better" unless you're optimizing a *serious* bottleneck.
I have a SafeArray class on my site that you can use to represent the
SAFEARRAY structure of any native array. You'd have to download that
(from
http://vb.mvps.org/samples/MapFile), and use code something like
this (indented to highlight wordwrap):
Private Declare Sub CopyMemory Lib "kernel32" Alias "RtlMoveMemory"
(Destination As Any, Source As Any, ByVal Length As Long)
Public Sub test()
Dim a() As Long
Dim b() As Long
Dim i As Long
Dim saA As CSafeArray
Set saA = New CSafeArray
Dim saB As CSafeArray
Set saB = New CSafeArray
ReDim a(1 To 100)
For i = LBound(a) To UBound(a)
a(i) = i
Next i
With saA
.AttachToArray a
ReDim b(.LowerBound To .LowerBound + .CountOfElements)
saB.AttachToArray b
Call CopyMemory(ByVal saB.PointerToData, _
ByVal .PointerToData, _
.SizeofElements * .CountOfElements)
End With
saA.ReleaseArray
saB.ReleaseArray
End Sub
Also, in CSafeArray, you'd want to redeclare the VarPtrArray function,
so that it works in VBA. This seems to do that, when I test here:
Private Declare Function VarPtrArray Lib "vbe6.dll" Alias "VarPtr"
(Var() As Any) As Long
Obviously, this is an *incredible* amount of work to go to, unless
you're saving some serious cycles in the process. Which is totally
possible! But if all you're trying to save is a bit of typing, well,
you'll want to reconsider more than a few things.
Hope this helps... Karl
