Store range of cells to an Array - arrays

I'm working with arrays and I'm sorry but I'm a bit new to it and still confused. I have already this code to store the values in a range in an array and if I run it, it is empty.
attPresent = ws.Range("H4:H" & lastrow)
ReDim attPresent(1 To UBound(attPresent))
For k = LBound(attPresent) To UBound(attPresent)
MsgBox attPresent(k)
Next
Can someone please tell me where I'm wrong? I've read any other posts and gather some ideas, but still not working.

You can go like this
Dim attPresent as Variant
attPresent = ws.Range("H4:H" & lastrow).Value '<-- this will automatically size the array to a 2dimensional array of as many rows as the range ones and one column
For k = LBound(attPresent,1) To UBound(attPresent,1)
MsgBox attPresent(k,1)
Next
Or
Dim attPresent as Variant
attPresent=Application.Transpose(Range("H4:H" & lastrow).Value) '<-- this will automatically size the array to a 1dimensional array of as many elements as the range
For k = LBound(attPresent) To UBound(attPresent)
MsgBox attPresent(k)
Next

Reference MSDN: ReDim Statement (Visual Basic)
When you Redim the array you are erasing all the values. Use ReDim Preserve to resize the last dimension of the Array and still preserve the values of the array.
After the dynamic array has been allocated(the first time Redim is used) you can only resize the last dimension of a array and you cannot change the number of dimensions. In your code you are trying to convert a 2 Dimensional array to a 1 Dimensional array, you can not do that.
You should watch this complete series: Excel VBA Introduction. This is the relevant video: Excel VBA Introduction Part 25 - Arrays

'Try this code example to suit your case
Sub StoreRangeofCellsToAnArray()
'presumes optionbase=0
'presume Range("a1:c3") contain number 1 to 9
Dim MyRange, MyArray(9), n
n = 0
For Each c In Range("a1:c3")
MyArray(n) = c
n = n + 1
Next
'testing: reprint array
For n = 0 To 8
Debug.Print MyArray(n)
Next
End Sub

Related

multi dimensional array with different elements; VBA excel

Is it possible to create multi dimensional array with different element types (string and integer)?
I tried like this but wan't work
BT = Range("A12")
ReDim IT(BT) As String
ReDim RBT(BT) As Integer
ReDim IT_RBT(IT, RBT) as ???? how to create multi dim array with different variables type
Range("B2").Select
i = 0
Do
i = i + 1
IT(i) = ActiveCell
RBT(i) = i
IT_RBT(i, i) = ???? how to enter values in such array ????
ActiveCell.Offset(1, 0).Select
Loop While ActiveCell <> ""
Thank you
Use a Variant array.
Dim values() As Variant
Now, your code is making assumptions that should be removed.
BT = Range("A12") '<~ implicit: ActiveSheet.Range("A12").Value
If you mean to pull the value of A12 from a particular specific worksheet, then you should qualify that Range member call with a proper Worksheet object. See CodeName: Sheet1 for more info, but long story short if that sheet is in ThisWorkbook you can do this:
BT = Sheet1.Range("A12").Value
And now assumptions are gone. Right? Wrong. BT isn't declared (at least not here). If it's declared and it's not a Variant, then there's a potential type mismatch error with that assignment. In fact, the only data type that can accept any cell value, is Variant:
Dim BT As Variant
BT = Sheet1.Range("A12").Value
Here, we're assuming BT is a numeric value:
ReDim IT(BT) As String
That's another assumption. We don't know that BT is numeric. We don't even know that it's a value that can be coerced into a numeric data type: we should bail out if that's not the case:
If Not IsNumeric(BT) Then
MsgBox "Cell A12 contains a non-numeric value; please fix & try again."
Exit Sub
End If
ReDim IT(BT) As String
Now that will work... but then, only the upper bound is explicit; is this a 0-based or a 1-based array? If the module says Option Base 1, then it's 1-based. Otherwise, it's 0-based - implicit array lower bounds are an easy source of "off-by-one" bugs (like how you're populating the arrays starting at index 1, leaving index 0 empty). Always make array bounds explicit:
ReDim IT(1 To BT) As String
Unclear why you need 3 arrays at all, and why you're only populating (i,i) in the 3rd one - you cannot populate a 2D array with a Do...Loop structure; you need every value of y for each value of x, and unless you hard-code the width of the array, that's a nested loop.
Moreover, looping on the ActiveCell and Selecting an Offset is making the code 1) very hard to follow, and 2) incredibly inefficient.
Consider:
Dim lastRow As Long
lastRow = Sheet1.Range("B" & Sheet1.Rows).End(xlUp).Row
ReDim values(1 To lastRow, 1 To 2) As Variant
Dim currentRow As Long
For currentRow = 2 To lastRow
Dim currentColumn As Long
For currentColumn = 1 To 2
values(currentRow, currentColumn) = Sheet1.Cells(currentRow, currentColumn).Value
Next
Next
Now, if we don't need any kind of logic in that loop and all we want is to grab a 2D variant array that contains every cell in B2:B???, then we don't need any loops:
Dim values As Variant
values = Sheet1.Range("A2:B" & lastRow).Value
And done: values is a 1-based (because it came from a Range), 2D variant array that contains the values of every cell in A2:B{lastRow}.
Note, code that consumes this array will need to avoid assumptions about the data types in it.
As #SJR has said, variant will allow for this. The below example is a easy example how to add different types to an array. Instead of x or y you can have a cell on a worksheet.
Dim array1() As Variant, i As Long
Dim x As String, y As Long
x = "5"
y = 1
For i = 1 To 10
ReDim Preserve array1(1 To 2, 1 To i)
array1(1, i) = x
array1(2, i) = y
y = y + 1
Debug.Print array1(1, i) & "," & array1(2, i) ' This is where you insert output
Next
You can do this:
BT = Range("A12")
ReDim IT(BT) As String
ReDim RBT(BT) As Integer
Dim IT_RBT(1 to 2) 'variant
IT_RBT(1) = IT 'add String array
IT_RBT(2) = RBT 'add Integer array
... this will keep your typed arrays functional but it's not a 2D array and you'd need to use notation like
IT_RBT(1)(1) 'String type
IT_RBT(2)(1) 'Integer type

how to populate and array with a loop

I have a strings in column "C", starting at C2 (for example: Cat, Dog, Bird, etc...) and I don't know how many. So I am using a LRow function to find the last row with data. Currently, the last row is C63 but this is expected to be different if I run the subroutine next week or next month (Hence why I said "I don't know how many"). I want to create an array for example RTArr = Array("Cat", "Dog", "Bird", etc...) So... I was thinking something like:
Dim RTArr As Variant
LRow = r.End(xlDown).Offset(x, y).Row
With ActiveSheet
For i = 2 To LRow
str = .Range("C" & i).Value
Next i
End With
Can I populate the array with something like:
Dim RTArr As Variant
LRow = r.End(xlDown).Offset(x, y).Row
With ActiveSheet
For i = 2 To LRow
ArrNum = (i - 1)
str = .Range("C" & i).Value
RTArr(ArrNum) = str
Next i
End With
Or does this not work because of the unknown size of the array? Or do I have to use "amend" in the loop? Would I be better off using a "collection" in this case? Or going about it some other way? Can I simply set a range of cells as an array without needing to loop?
If you declare a dynamic array at first (without the size), you need to ReDim it to the needed size before populating it, which in your case will be the number of rows e.g. ReDim RTArr(numberofitems). Or use a two dimensional array ReDim RTArr(numbercolumns, numberrows).
Remember that standard arrays begin at element 0, but you can define it however you like.
Remember that when inputting ranges into array Excel creates by default a two-dimensional array
More advanced techniques are possible of course, you can do some more research about VBA arrays regarding those:
1) you could ReDim the array after each element added inside of the loop, but this is mostly useful for one dimensional arrays.
2) you could define a much bigger size of array than needed before populating it, populate it, and then shrink the array to the actual size needed.
3) note that when using two (or more) dimensions ReDim Preserve works only on the last dimension.
Pseudo code for the basic populating:
Dim arr() as Variant
'we know we want to populate array with 10 elements
ReDim arr(1 to 10)
For i = 1 to 10
'This part will insert the count from the loop into the count position in array
' eg. first element of array will be a 1, second a 2 etc. until 10
arr(i) = i
Next i
If your version of Excel supports the TEXTJOIN function:
Sub Kolumn2Array()
Dim r As Range
Dim N As Long
Dim RTArray
Dim comma As String
comma = ","
N = Cells(Rows.Count, "C").End(xlUp).Row
Set r = Range("C2:C" & N)
With Application.WorksheetFunction
RTArray = Split(.TextJoin(comma, True, r), comma)
End With
End Sub

Error 424 when trying to delete element in array vba [duplicate]

This question already has an answer here:
Search for an element in the VBA ArrayList
(1 answer)
Closed 2 years ago.
I was trying to delete the specific element in the array vba when certain condition are true but i end up getting error 424. May I know the right way to do it? I tired to use redim, however it doesn't suit my condition as after the comparing with others array i need to store the data back into excel file where the location in the excel file is already sorted.
Before changing the remarkRange to array variant, I used it as Dim remarkRange
As Range where I can just use .Clear to clear the range item in a specific element.
I tried remarkRange(I, 1)=" " it runs without error but im not sure if its suitable. May I know the correct way to do it? Thanks.
Dim remarkRange() As Variant
remarkRange= wb.Sheets("wb").Range("A1:A5").Value2
For I = LBound(remarkRange) To UBound(remarkRange)
If (some condition is true) then
remarkRange(I, 1).Delete
End If
Next I
I expected the element in the specific cell in the array to be empty, but I got error 424
An array doesn't have a Delete method. It's also misleading to have the Range in remarkRange when it's an array, not a Range. Maybe a different name, e.g. remarks or whatever is clear to you.
If you're going to write the array back to the worksheet, then I see no problem changing an element to a blank string.
For i = LBound(remarks, 1) To UBound(remarks, 1)
If some condition Then
remarks(i, 1) = ""
End If
Next i
It seems you'll need to decide what you mean by 'delete'. I'm not aware of a Delete property of an array of variants so while your code might compile it would throw an object required error.
However, your point about previously using the Clear method on a Range object, suggests that you just want to read your range values into an array, remove the contents if certain conditions aren't me, and then re-write your array to the range. If that's the case, you probably wouldn't want to resize your array as the rows or columns wouldn't line up - more commonly, you'd set the item of your variant array to Empty.
The code below shows how to do this in a simple routine of taking 10 numbers from column A, removing all odd numbers and re-writing the numbers to Column C - but with the rows still matching:
Public Sub EmptyItemsAndKeepArraySize()
Dim inArr() As Variant
Dim i As Long
'Read range into arrays.
inArr = Sheet1.Range("A1:A10").Value2
'Clear all numbers that are not even.
For i = 1 To UBound(inArr, 1)
If inArr(i, 1) Mod 2 <> 0 Then inArr(i, 1) = Empty
Next
'Write cleared array to column C
Sheet1.Range("c1").Resize(UBound(inArr, 1)).Value = inArr
End Sub
If, however, you really do want to remove and resize your array, then a simple way of doing it is to populate a temporary collection first, resizing an output array and then populating that with the collection items. In the example below the code removes all odd numbers and then writes the array to column B - but as an array reduced in size (ie contiguous rows):
Public Sub DeleteItemsAndShrinkArray()
Dim inArr() As Variant, outArr() As Variant
Dim i As Long
Dim temp As Collection
Dim v As Variant
'Read range into arrays.
inArr = Sheet1.Range("A1:A10").Value2
'Keep all even numbers in a temporary collection.
Set temp = New Collection
For i = 1 To UBound(inArr, 1)
If inArr(i, 1) Mod 2 = 0 Then temp.Add inArr(i, 1)
Next
'Dimension the output array.
ReDim outArr(1 To temp.Count, 1 To 1)
'Populate new array from temp collection.
i = 1
For Each v In temp
outArr(i, 1) = v
i = i + 1
Next
'Write reduced array to column B
Sheet1.Range("B1").Resize(UBound(outArr, 1)).Value = outArr
End Sub

Dynamicall Add Arrays to create a 2D Array

I have looked at just about every post I could find on this topic, but I can't seem to get anything to work.
I want to be able to use a 2D Array for my own sake, but I think my best bet is to just make one huge 1D Array.
Sub GatherData()
Dim width As Integer: width = 22
Dim data() As Variant
ReDim roadway(width) As Variant
Dim str As Variant
Dim arrayWidth As Integer
With ThisWorkbook.Worksheets("List of Roads").Range("A1")
For r = 0 To 400 '400 is an arbitrary number
If Not IsEmpty(.Offset(r, 0).value) Then
If IsStreet(UCase(.Offset(r, 0).value), UCase(.Offset(r, 1).value)) Then
For c = 0 To width - 1
roadway(c) = .Offset(r, c).value
Next c
End If
'add roadway array to the end of data()
End If
Next r
End With
End Sub
If I had my way this 2D-Array would have an unknown number of rows with each row containing 22 columns. I just can't wrap my head around how I would dynamically add arrays together.
Dim data
data = ThisWorkbook.Worksheets("List of Roads").Range("A1").Resize(400, 22).Value
would give you a 2D array (1 to 400, 1 to 22)

return an entire row of a multidimensional array in VBA to a one dimensional array

Is there any way to return the value of an entire row of a multidimensional array to a one dimensional array In VBA?
Something like, arr_1dim = arr_2dim(3,:) is a matlab expression for assigning the row 3 of arr_2dim array to arr_1dim in one single stretch.
Is there any similar less expensive method in Excel VBA?
There is a simple way to get a column or a row of a two-dimensional array. Assign a zero to column to get the row, or assign a zero to row to get the column, thus:
Application.WorksheetFunction.Index(array, 0, columnyouwant) /* or */
Application.WorksheetFunction.Index(array, rowyouwant, 0)
See here:
How do I slice an array in Excel VBA?
No there is no VBA-function to get a row or column. You can only write it yourself, or take a look here:
http://www.cpearson.com/excel/vbaarrays.htm
This is what I do to easily print out one dimension of a multidimensional array.
Basically, I define a new, 1D array and stuff it with the values from the bigger array.
Example (3D to 1D to Printout):
Sub PrintItOut()
ReDim big_array(10,5,n) as Variant, small_array(n) as Variant
'use multidimensional array
'place multi-dimensional values into the 1D array
For i = 0 to n
small_array(i) = big_array(0, 0, i)
Next
Range(Cells(1, 1), Cells(1, n + 1)) = small_array
End Sub
That's how I do it. I hope that makes sense to whoever may be reading it. I think it's a very simple way to do it.
Matlab is such an awesome application to work when it comes to matrices, arrays, vectors... ;) But Excel is not that bad, it too is matrix based.
So Assuming you do not want to loop through. You may simply ouput your multi-D array into a worksheet using Transpose function.
Then pull a Row to your desired range size into an array using Transpose.
Dim vArr as Variant
'--output multi-D array into worksheet
Sheets(2).Range("E2").Resize(UBound(multiDArray) + 1, _
UBound(Application.Transpose(multiDArray))) = multiDArray
'--pull back the row you need: we double transpose here to get 1D. Coz single transpose
'-- results in 2D array..
vArr = WorksheetFunctions.Transpose( _
WorksheetFunctions.Transpose(Sheets(1).Range("A2:G2").Value))
To be absolutely dynamic, you may resize your range A2:G2 with a dynamic row count using the multi-D array row upperbound :)
Since I had this question by myself recently, I want to share my code. I wrote a ready-to-use function where you can choose if you want a column or a row to be extracted:
'*** Modul 1, define function ***
Function getOneLine(array2D As Variant, lineIndex As Integer, choice As String) As Variant
' returning one column or row of a 2D array
' array2D: 2 dimensional Array
' lineIndex: the index of column or row, starting at 0
' choice: "c" for column or "r" for row
Dim i, n As Integer
Dim oneLine As Variant
If choice = "c" Then
n = UBound(array2D, 2)
ReDim oneLine(n)
For i = 0 To n
oneLine(i) = array2D(lineIndex, i)
Next
getOneLine = oneLine
End If
If choice = "r" Then
n = UBound(array2D, 1)
ReDim oneLine(n)
For i = 0 To n
oneLine(i) = array2D(i, lineIndex)
Next
getOneLine = oneLine
End If
End Function
'*** Modul 2, call function ***
Sub SomeProcess()
' Creating a 3x2 Matrix
' (In VBA-arrays the column is indexed before the rows
' starting at 0. So 3x2 looks like 1x2)
Dim SomeArray(1, 2) As Variant
SomeArray(0, 0) = 1
SomeArray(0, 1) = 2
SomeArray(0, 2) = 3
SomeArray(1, 0) = 4
SomeArray(1, 1) = 5
SomeArray(1, 2) = 6
Dim oneLine As Variant
oneLine = getOneLine(SomeArray, 1, "c")
Debug.Print oneLine(2)
' prints 6
End Sub
A way to do something close:
ReDim TwoDim(10) As Variant
TwoDim(2) = Array("a", "b")
Debug.Print TwoDim(2)(1) 'Shows "a"
Debug.Print Join(TwoDim(2), "") 'Shows "ab"

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