Generate random numbers based on row and colum totals - excel

Question

I would like populate the blue area with random numbers.
sum of C3 to R3 should be equal to B3 value: 124
also;
sum of C3 to C26 should be equal to C2 value: 705
I tried to achieve it with the following code:
(this code was originally posted here: Code by #Mech
Sub RandomNumbersArray()
' dim your variables. this tells vba what type of variable it is working with
Dim lRow As Long
Dim wb As Workbook: Set wb = ThisWorkbook
Dim ws As Worksheet: Set ws = wb.Worksheets("SPLIT BY DAYS")
' find the last row in column b (2) in the above defined ws
lRow = ws.Cells(ws.Rows.Count, 2).End(xlUp).Row
' loop through rows 3 to last row
For i = 3 To lRow
' generate a random number between 0 and the row contents of column B (5)
ws.Cells(i, 3).Value = Int(Rnd() * (ws.Cells(i, 2).Value + 1))
' generate a random number between 0 and the difference between column B and colum C
ws.Cells(i, 4).Value = Int(Rnd() * (ws.Cells(i, 2).Value - ws.Cells(i, 3).Value))
' subtract the difference between column B and the sum of column C and column D
ws.Cells(i, 5).Value = ws.Cells(i, 2).Value - (ws.Cells(i, 3).Value + ws.Cells(i, 4).Value)
' subtract the difference between column B and the sum of column C and column D and column E
ws.Cells(i, 6).Value = ws.Cells(i, 2).Value - (ws.Cells(i, 3).Value + ws.Cells(i, 4).Value + ws.Cells(i, 5).Value)
' subtract the difference between column B and the sum of column C and column D and column E and column F
ws.Cells(i, 7).Value = ws.Cells(i, 2).Value - (ws.Cells(i, 3).Value + ws.Cells(i, 4).Value + ws.Cells(i, 5).Value + ws.Cells(i, 6).Value)
Next i
' sum column C (column 3) and place the value in C2
ws.Cells(2, 3).Value = Application.WorksheetFunction.Sum(Range(Cells(3, 3), Cells(lRow, 3)))
' sum column D (column 4) and place the value in D2
ws.Cells(2, 4).Value = Application.WorksheetFunction.Sum(Range(Cells(3, 4), Cells(lRow, 4)))
' sum column E (column 5) and place the value in E2
ws.Cells(2, 5).Value = Application.WorksheetFunction.Sum(Range(Cells(3, 5), Cells(lRow, 5)))
' sum column F (column 6) and place the value in F2
ws.Cells(2, 6).Value = Application.WorksheetFunction.Sum(Range(Cells(3, 6), Cells(lRow, 6)))
' sum column G (column 7) and place the value in F2
ws.Cells(2, 7).Value = Application.WorksheetFunction.Sum(Range(Cells(3, 7), Cells(lRow, 7)))
End Sub
EDIT: Just to clarify, no negative numbers.

Answer 1

Here is something to try:
Set all cells to 0. Create a list of all cells (some kind of reference to each cell).
Now, randomly choose a cell from your list, and add 1 to that cell. The very first time, all cells will be 0, except for one, which will now be 1.
For this cell that you just incremented, add up the row and column and see if the sums have been reached. If either the row or the column sum has been reached, remove this cell reference from the list.
Repeat (randomly choose a cell from those remaining on the list) until the list is empty.
At each iteration you are randomly choosing one of the remaining cells in the reference list (not choosing from all the cells) and this list is getting smaller and smaller as column or row sums are reached.
It should be the case that random cells will increment, and if the columns and sums can in fact be calculated by values without logical inconsistencies, you should fairly quickly reach that point when the reference list falls empty.

Answer 2

I have a solution.
Answers so far have mostly been about finding values which are random, then fixing them to fit the totals.
I tried finding a calculated (non random) solution that fits the totals, then made a separate sub to randomize it. This way you can prevent the randomization from introducing negative values.
There are two procedures, This sub will call them both on the same Range.
Sub Call_Random_Array
Dim wb As Workbook: Set wb = ThisWorkbook
Dim ws As Worksheet: Set ws = wb.Worksheets("SPLIT BY DAYS")
Dim RangeToFill as Range: Set RangeToFill = ws.Range("C3:R26") 'Edit this line to select whatever range you need to fill randomly
'Proportionately fill the array to fit totals:
Call ProportionateFillArray(RangeToFill)
'Randomize it x times
For x = 1 to 10 'increase this number for more randomisation
Call RandomizeValues(RangeToFill)
Next
End Sub
Proportionately fill the array to fit totals:
Sub ProportionateFillArray(rngAddress As Range)
Dim ws As Worksheet: Set ws = rngAddress.Worksheet
'Horizontal and Vertical target values as ranges:
Dim hTarg As Range, vTarg As Range
Set hTarg = rngAddress.Rows(1).Offset(-1, 0)
Set vTarg = rngAddress.Columns(1).Offset(0, -1)
'Check the totals match
If Not WorksheetFunction.Sum(hTarg) = WorksheetFunction.Sum(vTarg) Then
'totals don't match
MsgBox "Change the targets so both the horizontal and vertical targets add up to the same number."
Exit Sub
End If
With rngAddress
'Now fill rows and columns with integers
Dim Row As Long, Col As Long
For Row = 1 To .Rows.Count
For Col = 1 To .Columns.Count
.Cells(Row, Col) = Int( _
hTarg.Cells(Col) * vTarg.Cells(Row) / WorksheetFunction.Sum(hTarg) _
)
Next
Next
'Correct rounding errors
For Row = 1 To .Rows.Count
For Col = 1 To .Columns.Count
If Row = .Rows.Count Then
'Last row, so this column must be corrected come what may
.Cells(Row, Col) = .Cells(Row, Col) - WorksheetFunction.Sum(.Columns(Col)) + hTarg.Cells(Col)
ElseIf Col = .Columns.Count Then
'Last column, so must be corrected come what may
.Cells(Row, Col) = .Cells(Row, Col) - WorksheetFunction.Sum(.Rows(Row)) + vTarg.Cells(Row)
ElseIf _
(WorksheetFunction.Sum(.Rows(Row)) - vTarg.Cells(Row)) * _
(WorksheetFunction.Sum(.Columns(Col)) - hTarg.Cells(Col)) > 0 Then
'both row and column are incorrect in the same direction
.Cells(Row, Col) = .Cells(Row, Col) - WorksheetFunction.Max( _
WorksheetFunction.Sum(.Rows(Row)) - vTarg.Cells(Row), _
WorksheetFunction.Sum(.Columns(Col)) - hTarg.Cells(Col))
End If
Next
Next
End With
End Sub
Randomize an array without changing row or column totals:
Sub RandomizeValues(rngAddress As Range)
Dim ws As Worksheet: Set ws = rngAddress.Worksheet
Dim rngIncrease(1 To 2) As Range, rngDecrease(1 To 2) As Range, lDiff As Long
With rngAddress
'Select two cells to increase at random
For a = 1 To 2
Set rngIncrease(a) = .Cells(RndIntegerBetween(1, .Rows.Count), RndIntegerBetween(1, .Columns.Count))
rngIncrease(a).Select
Next
'Corresponding cells to decrease to make totals the same:
Set rngDecrease(1) = ws.Cells(rngIncrease(1).Row, rngIncrease(2).Column)
Set rngDecrease(2) = ws.Cells(rngIncrease(2).Row, rngIncrease(1).Column)
'Set the value to increase/decrease by - can't be more than the smallest rngDecrease Value, to prevent negative values
If Not WorksheetFunction.Min(rngDecrease) > 1 Then
'Don't decrease a value below 1
Exit Sub
Else
lDiff = RndIntegerBetween(1, WorksheetFunction.Min(rngDecrease)-1)
End If
'Now apply the edits
For a = 1 To 2
rngIncrease(a) = rngIncrease(a) + lDiff
rngDecrease(a) = rngDecrease(a) - lDiff
Next
End With
End Sub
'The below is the Random Integer function, I also used it in my other answer
Function RndIntegerBetween(Min As Long, Max As Long) As Long
RndIntegerBetween = Int((Max - Min + 1) * Rnd + Min)
End Function

Answer 3

This code is for what you were trying to do, not exactly how you explained it though (see comments). If this is what you were looking for, then your explanation was a bit off, otherwise let me know what you did mean.
Sub RandomNumbersArray()
Dim lRow As Long, lColumn As Long, remainingValue As Long
Dim wb As Workbook: Set wb = ActiveWorkbook
Dim ws As Worksheet: Set ws = wb.Worksheets("SPLIT BY DAYS")
lRow = ws.Cells(ws.Rows.Count, 2).End(xlUp).Row
lColumn = ws.Cells(2, ws.Columns.Count).End(xlToLeft).Column
For i = 3 To lRow 'loop through the rows
remainingValue = ws.Cells(i, 2).Value2
For j = 3 To lColumn 'loop through all the columns per row
' generate a random number between 0 and the row contents of column B - previous column
If j = lColumn Then 'last cell can't be random unless you want to extend the columns until the sum in B-column is met
ws.Cells(i, j).Value2 = remainingValue
Else
ws.Cells(i, j).Value2 = Int((remainingValue + 1) * Rnd)
End If
remainingValue = remainingValue - ws.Cells(i, j).Value2
Next j
Next i
For j = 3 To lColumn 'loop through the columns to set the sum
ws.Cells(2, j).Value2 = Application.WorksheetFunction.Sum(Range(Cells(3, j), Cells(lRow, j)))
Next j
End Sub
I'm yet to get past the O-column with any value above 0 however