I have a formula assigned to a name in excel which is slow to calculate.
Let's say it's this:
Name: ImportantItems
Scope: Workbook
RefersTo: =FILTER(A1:A10000, complexCondition(A1:A10000))
I have some VBA macros which run a simulation that modifies A1:A10000 on every iteration, however the simulation only needs to access the ImportantItems array every 100 iterations. If
=FILTER(A1:A10000, complexCondition(A1:A10000))
... was a normal formula in a cell, I know that Excel would observe its precedent (A1:A10000) had changed and trigger a recalc every iteration. However I'm hoping named ranges not referred to in the spreadsheet anywhere - only via VBA - will be calculated on demand. FWIW my VBA code is just
Dim items As Variant 'read fancy filtered array of stuff into 1D array
items = Application.Transpose(Sheet1.Range("ImportantItems").Value)
My alternative is to refactor and move the ImportantItems code into VBA so I can control when it is calculated. Application.Calculations = xlManual is not an option without sprinkling my code with ...
Anyway this isn't meant to be an A/B question, I'm just wondering how the calculation engine works as I can't find documentation on it, and it will influence future design decisions.
Your hope/assumption is correct. As long as the named range is not referred to in the workbook in any range (other named ranges don't count) then the formula in the named range is not recalculated when the source range is changed.
The reason it doesn't recalculate is because the named range is storing a formula string (see Name object .RefersTo in VBA). Excel propagates the change (in source) only if the named range is referenced from a range at which point it runs an Evaluate on the formula string. When the source is resized (cut/insert/delete cells), the named range formula string is updated but in essence it's still a string.
To test, create the following named range:
Name: TestCalc
Scope: Sheet1
Refers to: =NamedRangeWatch(Sheet1!$A$1:$A$5)
Then add the following code in a standard .bas VBA module:
Option Explicit
Public Function NamedRangeWatch(ByVal rng As Range) As Range
Application.Volatile False
Debug.Print "NamedRangeWatch was called at " & Now
Set NamedRangeWatch = rng
End Function
Sub Test()
Dim i As Long
For i = 1 To 10
Sheet1.Range("A1:A5").Value2 = i
If i Mod 5 = 0 Then
Debug.Print Application.Sum(Sheet1.Names("TestCalc").RefersToRange)
'Or
'Debug.Print Application.Sum(Sheet1.Range("TestCalc").Value)
End If
Next i
End Sub
and then run the Test method. You should see something like:
which shows that the function inside the named range only gets called twice although the source range was changed 10 times.
Related
I'm trying to loop through the multiple named ranges, every range is just one cell, on a column, so it starts with item1, item2...item100.Each of these ranges has a cell reference in it (like "AM100").
I want to be able to set up a for/while loop that just selects(and does something) each of the referenced cells in those named ranges.
I'm stuck at VBA not considering "item"&"1" the same with "item"&"i" when i =1 and from what I deduct this is purely a data type issue. It's able to refer to a pure string range but when it's variant/string type (which any concatenation of string or converted string variable results in).
item1 range has in it $AM$10 reference. That cell, has a value in it. Eventually I want to change the values in multiple similar cells by referring to the name ranges that hold their reference.
Without the "for" loop, I've tested the following:
Sub test()
Dim i as integer
i=1
'These don't work
Range([indirect("item"&CSTR(i))]).Select
Range([indirect("item"&i)]).Select
'What works is, but this is not useful since I want to loop through i:
Range([indirect("item" & "1")]).Select
Range([indirect("item1")]).Select
Sub Test()
Dim oDefName As Name
For Each oDefName In ThisWorkbook.Names
If Left(UCase(oDefName.Name), 4) = "ITEM" Then
Range(oDefName.RefersToRange.Value).Select
End If
Next
End Sub
Note: There is no error checking to ensure that the value within the named range is actually a cell reference.
Edit- Above is how I would solve the problem. Indirect is an in cell function and not usable directly in vba. Below is how you would get the indirect functionality in VBA with a counter.
Range(Range("Item" & oCounter).Value).Select
I tried to work a bit more with dynamic arrays in excel in combination with vba. My problem is that I cant return a table-column with vba. Here a minimal example of what I want to do:
I have two Tables TabFeb and TabMar (see image below). Each of them has a column costs which I want to sum up individually. The results shall be put into a new Table. This can be easily done in excel with =SUM(TabFeb[Costs]) and =SUM(TabMar[Costs]), respectively. My idea is now to write a VBA function which takes a string as input, in this example it will be the month, and returns the table acording to the input. After that it will be summed up and the result is given in a cell.
I tried the following:
Function Selectmon(mon As String) As Range
If mon = "Feb" Then
Set Selectmon = Worksheets("Sheet1").ListObjects("TabFeb").ListColumns("Costs").DataBodyRange
ElseIf mon = "Mar" Then
Set Selectmon = Worksheets("Sheet1").ListObjects("TabMar").ListColumns("Costs").DataBodyRange
End If
End Function
The problem of this idea is that this function just copy the table data. Hence, if I would change the input table data the sum would not change. One has to recalculate every cell by hand. Somehow I need VBA to return TabFeb[Costs] for the input "Feb". Does anyone have an idea how this can be done?
Example
It's really just a one-liner (unless you want to do some in-function error checking)
Function Selectmon(mon As String) As Range
Set Selectmon = Range("Tab" & mon & "[Costs]")
End Function
As implied by #ceci, this formula will not update with changes in the table. Depending on other particulars of your worksheet, you can have it update either by
embedding it in a worksheet change event code;
or by adding the line Application.Volatile to the function itself.
The latter method will force a recalculation when anything changes on the worksheet that might cause a recalculation.
The first method can limit the recalculation only when there has been a change in the data, but has other limitations.
One of the limitations of the Worksheet Change method is that it will only work on the relevant worksheet.
If you use the Workbook sheet change method, you won't have that limitation.
In either event you can limit your code to run only when the table has changed.
Here is one generalized method:
Option Explicit
Private Sub Workbook_SheetChange(ByVal Sh As Object, ByVal Target As Range)
Dim LOS As ListObjects
Dim LO As ListObject
Set LOS = Sh.ListObjects
For Each LO In LOS
'could select relevant tables here
'Could also select relevant worksheets, if you like
'for example
Select Case LO.Name
Case "TabFeb", "TabMar", "TabApr"
If Not Intersect(LO.DataBodyRange, Target) Is Nothing Then
Application.EnableEvents = False
Application.Calculate
End If
End Select
Next LO
Application.EnableEvents = True
End Sub
And there is other code you could use to find the relevant formula and just update that formula -- probably not worth the effort.
First time posting, apologies if I make any mistakes!
So, I'm having a pretty strange problem with my UDF. In my workbook, I have an invisible 'template' sheet named "Standard Phase Sheet", and a subroutine that a user can activate which copies that template sheet into a new, visible sheet that the user can then work with. There will be many copies of that template sheet throughout the workbook, but they will all have unique names.
My UDF is on that template sheet in several spots, and thus on every copy of the template sheet that a user makes. When working within one of these sheets, the UDF works just fine, and returns the values I'd expect.
However, when a user ADDS a new copy of the template sheet, SOMETIMES the UDF goes haywire and returns #VALUE errors in every place the UDF is being used.
Also, when a user DELETES one of the copies of the template sheet, the UDF ALWAYS goes haywire and returns #VALUE errors in every place the UDF is being used.
I'm not using ActiveSheet or anything like that, and I believe I'm correctly giving full references to the ranges I'm working with within the UDF. Any help will be appreciated, I'm in a bind here! Code for the UDF is below.
Also, because I'm sure I'll be asked the question, the neColumn variable within my code is a public variable that I use in several subroutines and UDFs. It is defined at the beginning of my module. Also, I am using Option Explicit at the beginning of my module as well.
Thank you!
Public Function fSum(ByVal Target As Range, bExtended As Boolean) As Single
'This function returns a sum, based on a range provided in the cell that holds the function.
'It checks to see if that line item has been marked as Non-Extended, based on the NE column
'that can be check marked. If that line item is marked NE, then only the NE sum columns can
'use that line item as part of their sum, and those values are removed from the E columns.
Dim sSum As Single
Dim i As Integer
Dim n As Integer
'This small section is used to determine complete references to the cell calling the function.
Dim sheetName As String
sheetName = Application.Caller.Parent.Name
'Loop through provided range, and sum up the contents based on whether they have been marked NE or not.
i = 1
n = Target.row
sSum = 0
If Sheets(sheetName).Visible = True Then
While i < Target.Rows.Count
If (bExtended = True) Then
If Sheets(sheetName).Range(neColumn.Address).Cells(n, 1) = vbNullString Then
sSum = sSum + Sheets(sheetName).Range(Target.Address).Cells(i, 1).Value
End If
Else
If Sheets(sheetName).Range(neColumn.Address).Cells(n, 1) <> vbNullString Then
sSum = sSum + Sheets(sheetName).Range(Target.Address).Cells(i, 1).Value
End If
End If
i = i + 1
n = n + 1
Wend
End If
fSum = sSum
End Function
Summarizing the comment thread in an answer for posterity:
I'm not sure why exactly you see this behavior.
There would be ways to better this UDF (including using Long instead of Integer, preferring a Do While...Loop to While...Wend, removing the .Visible check...
But in any case, it does feel like this is just replicating the functionality of SUMIFS so you might just consider going that route.
The reason is that your neColumn variable has become Nothing, because Excel is Volatile.
I assume that the start of your module looks something like this:
Option Explicit
Public neColumn As Range
Sub Auto_Open()
Set neColumn = Sheet1.Range("A1:B2")
End Sub
When you open the Workbook, you call the Auto_Open Sub to Set the neColumn variable. However - when certain actions occur, Excel rebuilds the VBA, which resets the Public Variables (such as neColumn) to their defaults (which, for an Object such as a Range, is Nothing). An easy way to trigger this is by deliberately throwing an error, such as attempting to run this:
Sub ThrowErr()
NotDefined = 1
End Sub
You can make it more visible to you by adding the following line to your fSum code:
If neColumn Is Nothing Then Stop
You either need a way to restore neColumn when it has been reset to Nothing, OR find a non-volatile way to store it.
I am assuming that this is not suitable to become a Const, because otherwise it already would be but you could turn it into a Named Range, or store the Address in a hidden worksheet / CustomDocumentProperty. These options would also allow you to store neColumn when the Workbook is saved for when you reopen it
I added a simple Previous Sheet macro to file and it worked normally, until it started to return #NAME error, and i can't figure out why.
I meant to use it with named single cell ranges which are consistent across the workbook, I'd used it successfully before naming the ranges and didn't think it would have any impact on the fuction. After naming the ranges though it no longer works, not even for regular non named ranges.
I have tested this by creating a new workbook, filling some sheets and trying it out, and it still returns a #NAME error. When i evaluate the function, the error appears at the very first step: recognizing the function. However, when i type into the formula bar, the programs offers me the formula normally.
I have also tried referring to the named cells by its cell, and even adding the worksheet name before the cell (eg "prevsheet(previoussheetname!a1), or prevsheet(thissheetname!a1)). I have even, in a last ditch effort, tried adding double quotes before the cell name.
For full disclosure, i have also another macro subroutine that uses references to previous and next sheets, but as it wouldnt recognize the function itself (which should have been an early sign), it makes use of relative referencing (ie activesheet(index - 1, activesheet(index + 1)). At the time i didn't think it would mess up the function, but as i grow ever more desperate and confused, maybe thats a possibility.
the PrevSheet() code i was using:
Function PrevSheet(RCell As Range)
Dim xIndex As Long
Application.Volatile
xIndex = RCell.Worksheet.Index
If xIndex > 1 Then _
PrevSheet = Worksheets(xIndex - 1).Range(RCell.Address)
End Function
And as it is now, as suggested by Chris Neilsen
Function PrevSheet(RCell As Range) As Variant
Application.Volatile
PrevSheet = RCell.Worksheet.Previous.Range(RCell.Address).Value
End Function
As suggested by Chris Neilsen i have edited the named ranges to look like this:
!(nothing)$column$row with its scope set to Workbook
The named range is not available at the range browser.
Only cell B1 is named. It is called "name"
PrevSheet() does not work with either range.
Macros are enabled
Anyone with a better understanding of vba, macros and excel can tell me why this is happening and how do i fix it so it returns the value of the specified cell in the first sheet to the left of sheet the function is typed in? (ie, in sheet4, =prevsheet(A1) will return the value of cell A1 in sheet3)
I hope my question is clearer now!
Your code appears to work if it is placed in a Standard Module:
Public Function PrevSheet(RCell As Range) As Variant
Dim xIndex As Long
Application.Volatile
xIndex = RCell.Worksheet.Index
MsgBox xIndex
If xIndex > 1 Then
PrevSheet = Worksheets(xIndex - 1).Range(RCell.Address)
End If
End Function
For example, in the worksheet:
I have assigned cell A7 the Name junk and the 666 is the value in the previous sheet's cell A7.
This will work, if you define your Named Ranges correctly. There are several ways this can be done, but here's one that is IMO simplest.
Since you say ...use it with named single cell ranges which are consistent across the workbook. you can create a single Named Range, Workbook scope, that will refer to a cell (or cells) on the sheet which references the name.
Lets say you want to refer to cell A1. In Name Manager, create a Name, lets say YourNamedRange workbook scope, Reference =!$A$1 (Note the ! without a sheet reference).
When you add a formula to a sheet (eg =YourNamedRange) it will refer to cell A1 on the sheet containing the formula.
Applying it to your UDF, just use =PrevSheet(YourNamedRange)
Your UDF works (mostly) as is, but will fail if a different Workbook is active. To fix that, use
Function PrevSheet(RCell As Range)
Dim xIndex As Long
Application.Volatile
xIndex = RCell.Worksheet.Index
If xIndex > 1 Then
With RCell.Worksheet.Parent 'The workbook containing RCell
PrevSheet = .Worksheets(xIndex - 1).Range(RCell.Address)
End With
End If
End Function
There is also a WorksheetProperty called Previous that does much the same thing, so you can refactor as
Function PrevSheet(RCell As Range) As Variant
Application.Volatile
PrevSheet = RCell.Worksheet.Previous.Range(RCell.Address).Value
End Function
EDITED WITH BETTER EXAMPLE
I'm trying to use the Evaluate function to evaluate a formula reference for a named range. However, when using the Evaluate function, if you do not explicitly state the sheet reference along with the cell reference, it will assume the active sheet as the cell reference. This causes the wrong result
In my real project I'm trying to only evaluate a part of the named range's formula, so it makes it even trickier.
Using a basic example of what I'm trying to do, let's say you have the following formula in Sheet 1 cell A1 whose name is MyCell:
="Don't evaluate this part"&"My Result Is " & A2
If the Active Sheet is Sheet 2 and you run the following code it will give you the wrong results (this is a quick and dirty example to illustrate the problem)
Dim s As String
s = Replace(Range("MyCell").Formula, """Don't evaluate this part""&", "")
Debug.Print Evaluate(s)
Instead of giving me the value that is in cell A2 of Sheet 1, it gives me the value that is in cell A2 of Sheet2.
Any ideas around this?
This is closest I found, but it is not my exact problem (despite similar titles) and it doesn't provide a solution:
Excel VBA evaluate formula from another sheet
The problem you are having is that by design Excel will assume all unspecific cell references are referring to the existing worksheet. This is why whenever possible it is recommended to explicitly state the worksheet in all code.
The cleanest way (verified with some MSDN definintion hunting) is to just explicitly state the worksheet without activating it:
Sub test2()
Debug.Print Range("MyCell").Worksheet.Evaluate(Range("MyCell").Formula)
End Sub
Alternatively this code will change the active worksheet to the correct one and then change it back after evaluation. Not recommended to perform sheet activations like the code below without extenuating circumstances. Not even here.
Sub test()
Dim ws As Worksheet
Set ws = ActiveSheet
Dim s As String
s = Replace(Range("MyCell").Formula, """Don't evaluate this part""&", "")
Range("MyCell").Worksheet.Activate ' Don't remember if .Worksheet or .Parent ??
Debug.Print Evaluate(s)
ws.Activate
End Sub
As pointed out in the comments by ThunderFrame, it is important to remember that this code assumes MyCell is a simple cell reference as stated in the question. Otherwise you will need to use other methods to determine the target worksheet name (or hardcode it).
Its nearly always better to use Worksheet.Evaluate rather than the default Application.Evaluate: as Mark Balhoff points out that allows you to control unqualified references.
But Worksheet.Evaluate is also usually twice as fast as Application.Evaluate.
See my blog post here for details
https://fastexcel.wordpress.com/2011/11/02/evaluate-functions-and-formulas-fun-how-to-make-excels-evaluate-method-twice-as-fast/
Your line:
Debug.Print Evaluate(Range("MyCell").Formula)
is equivalent to:
Debug.Print Evaluate("=""My Result Is "" & A2")
which is why you get results according to the value of A2 in the ActiveSheet.
If you want to inspect the contents of the formula, you can use this line:
Debug.Print [MyCell].Formula
If you want the value of MyCell with respect to Sheet1, then you have 2 options:
1 - Use Debug.Print Range("Sheet1!MyCell").Value
2 - Use Debug.Print Sheet1.Range("MyCell").Value