Can I give an if statement by subtracting time? - excel

Question

Is there a way to make my VBA code work for my macro? I want my macro's if function to read the first column of each worksheet in my excel (it has as many sheets as days in the exact month i'm working on), read through each cell and if the currently read cell is equal to or larger than '15 minutes compared to the first cell, then the code would execute, otherwise go to the next cell in the first column.
This is the format of the worksheets i'm working on:
TimeStamp
Power Consumption
Power Production
Inductive Power Consumption
2021.01.01. 8:12:38 +00:00
747
575
3333
2021.01.01. 8:17:35 +00:00
7674
576
3333
... etc ,
And my code looks something like this:
Sub stackoverflow()
Dim w As Integer 'index of worksheets
Dim i As Integer 'row index that steps through the first column
Dim t As Integer 'reference row index i inspect the time to
Dim x As Integer 'row index where i want my data to be printed
Dim j As Integer 'col index
Dim Timediff As Date 'not sure if this is even needed
t = 2
j = 1
x = 1
'Timediff = ("00:15:00")
For w = 3 To ActiveWorkbook.Worksheets.Count 'for every sheet from the 3rd to the last
lRow = ActiveWorkbook.Worksheets(w).Cells(Rows.Count, 1).End(xlUp).Row 'find the last row in each worksheet
lCol = ActiveWorkbook.Worksheets(w).Cells(1, Columns.Count).End(xlToLeft).Column 'find the last column in each worksheet
For x = 2 To lRow
For i = 2 To lRow
'If the time in cell(i,j) is >= then cell(t,j) + 15 minutes,
If Cells(i, j) >= DateAdd("n", 15, Cells(t, j)) Then
ActiveWorkbook.Worksheets(w).Range(i, j).Copy ActiveWorkbook.Worksheets(2).Range(x, j)
ActiveWorkbook.Worksheets(w).Range(i, j + 1).Copy ActiveWorkbook.Worksheets(2).Range(x, j + 1)
'put the new reference point after the found 15 minute mark
t = i + 1
Else
End If
Next i
Next x
Next w
End Sub
So all in all I want my code to notice when the first column reaches a 15 minute mark, and execute some code (subtracting the values of the 15 minute mark from the reference where it started, put the value in the'2nd sheet, and then step to the next cell, and repeat the process).

Answer 1

I'm not entirely sure which information you are attempting to copy to the second worksheet but the following code should be able to get you there pretty easily. Additionally, I've added a function that will fix the format of your TimeStamp field so that excel will recognize it and we can then do math with it
Sub TestA()
Dim xlCellA As Range
Dim xlCellB As Range
Dim xlCellC As Range
Dim i As Integer
Dim j As Integer
Dim lRow As Long
Dim lCol As Long
Set xlCellA = ActiveWorkbook.Worksheets(2).Cells(2, 1)
For i = 3 To ActiveWorkbook.Worksheets.Count
lRow = ActiveWorkbook.Worksheets(i).Cells.SpecialCells(xlCellTypeLastCell).Row
lCol = ActiveWorkbook.Worksheets(i).Cells.SpecialCells(xlCellTypeLastCell).Column
Set xlCellB = ActiveWorkbook.Worksheets(i).Cells(2, 1)
xlCellB.Value = FixFormat(xlCellB.Value)
xlCellB.Offset(0, lCol + 1).Value = "=DATEVALUE(MID(" & xlCellB.Address & ",1,10))+TIMEVALUE(MID(" & xlCellB.Address & ",12,8))"
For j = 3 To lRow
Set xlCellC = ActiveWorkbook.Worksheets(i).Cells(j, 1)
xlCellC.Value = FixFormat(xlCellC.Value)
xlCellC.Offset(0, lCol + 1).Value = "=DATEVALUE(MID(" & xlCellC.Address & ",1,10))+TIMEVALUE(MID(" & xlCellC.Address & ",12,8))"
If xlCellC.Offset(0, lCol + 1) - xlCellB.Offset(0, lCol + 1) >= ((1 / 24) / 4) Then
With xlCellA
.Value = xlCellC.Value
.Offset(0, 1).Value = xlCellC.Offset(0, 1).Value
End With
Set xlCellA = xlCellA.Offset(1, 0)
End If
Next j
Next i
Set xlCellA = Nothing
Set xlCellB = Nothing
Set xlCellC = Nothing
End Sub
Private Function FixFormat(ByVal dStr As String) As String
Dim tmpStr As String
Dim i As Integer
For i = 1 To Len(dStr)
If Mid(dStr, i, 1) <> "." Then
tmpStr = tmpStr & Mid(dStr, i, 1)
Else
If Mid(dStr, i + 1, 1) <> " " Then tmpStr = tmpStr & "-"
End If
Next i
FixFormat = tmpStr
End Function

Answer 2

It's not really clear what needs to happen when the 15min threshold is met but this should get you most of the way there:
Sub stackoverflow()
Dim w As Long, Timediff As Double
Dim wb As Workbook, wsData As Worksheet, wsResults As Worksheet, col As Long
Dim baseRow As Range, dataRow As Range, rngData As Range, resultRow As Range
Timediff = 1 / 24 / 4 '(15min = 1/4 of 1/24 of a day)
Set wb = ActiveWorkbook 'or ThisWorkbook
Set wsResults = wb.Worksheets("Results")
'first row for recording results
Set resultRow = wsResults.Cells(Rows.Count, 1).End(xlUp).Offset(1, 0).EntireRow
For w = 3 To wb.Worksheets.Count 'for every sheet from the 3rd to the last
Set rngData = wb.Worksheets(w).Range("A1").CurrentRegion 'whole table
Set rngData = rngData.Offset(1, 0).Resize(rngData.Rows.Count - 1) 'exclude headers
Set baseRow = rngData.Rows(1) 'set comparison row
For Each dataRow In rngData.Rows 'loop over rows in data
If (dataRow.Cells(1).Value - baseRow.Cells(1).Value) > Timediff Then
resultRow.Cells(1).Value = dataRow.Cells(1) 'copy date
For col = 2 To dataRow.Cells.Count 'loop columns and subtract
resultRow.Cells(col).Value = _
dataRow.Cells(col).Value - baseRow.Cells(col).Value
Next col
Set resultRow = resultRow.Offset(1, 0)
Set baseRow = dataRow.Offset(1, 0) 'reset comparison row to next row
End If
Next dataRow
Next w
End Sub