I'm trying to shuffle elements between a certain number of indexes.
Dim rng As New Random()
For placeHolder As Integer = min To max Step -1
Dim swapIndex As Integer = rng.Next(min, max)
Dim temp As Object = myList(placeHolder)
myList(placeHolder) = myList(swapIndex)
myList(swapIndex) = temp
Next
Where 'min' is the value of the lowest index and 'max' is the value of the highest index. However each time I have tried it doesn't seem to be shuffling randomly (it always comes out alphabetically instead).
Try this:
Dim rng As New Random()
For placeHolder as Integer = min To max-1 Step 1
Dim swapIndex as Integer = rng.Next(placeHolder +1, max)
Dim temp as Object = myList(placeHolder)
myList(placeHolder) = myList(swapIndex)
myList(swapIndex) = temp
Next
The changes?
I changed the max value being stepped over to 1 less than the end so that you don't waste time trying to swap the end with itself. I also changed the Step to +1 because min < max from your description. I changed the minimum random value to placeholder + 1 because I don't want to re-swap what I've already swapped. This last change is optional though.
if min is the lowest and max is the highest, then your loop should not have Step -1 in it. That will cause the loop to never execute.
Related
I have a dynamic table range of certain values (amounts). These amounts are generated into the table through a macro I've created.
What I want to do: Rank these amounts into the empty column by number.
eg. the cell in Column G next to 89k would be ranked as 1, one next to 77k would be 2 etc.
I also already have other functions defined, which I'm not going to explain here for readability reasons, but all you need to know: there are two variables obtained through functions
tbl_first = (int) Index of the ListRow of the first table item (so in this case it would be the row with 89k = 1st row so in this example 1)
tbl_last = (int) same as above, but indexes the last row (77k) in this example as 7
so my code is the following
' sets the tbl variable to the red table in the picture
Dim tbl As ListObject: Set tbl = Sheets("Summary").ListObjects("time_top")
Dim pos As Integer, diff as integer
diff = tbl_last - tbl_first
For j = tbl_first To tbl_last ' loops through all the added rows
For n = 1 to diff' indexing for the large function
' index the pos through the excel large function for our values (should return the k-th position from the largest value)
pos = Application.WorksheetFunction.Large(Range(Cells(tbl_first, 6), Cells(tbl_last, 6)), n)
With tbl.ListRows(1)
.Range(j, 6) = pos ' add the value to the column G to the right
End With
Next n
Next j
So the expected result would look like this:
I also keep getting the following error, which is caused by me incorrectly assigning the pos value.
Either way, probably multiple of things wrong here and much more elegant solution is out there, that just didn't hit me yet.
Think you need Rank (watch out for equal ranks). Large returns the nth largest value of a set.
Here is a simple example on a two column table which perhaps you can adapt. The rank is added in the second column.
Sub xx()
Dim tbl As ListObject: Set tbl = Sheets("Summary").ListObjects("time_top")
Dim r As Range
For Each r In tbl.ListColumns(1).DataBodyRange
r.Offset(, 1) = WorksheetFunction.Rank(r, tbl.ListColumns(1).DataBodyRange)
Next r
End Sub
I am trying to find max value of a loop. First, I have two random arrays and I want to find these two arrays correlation coefficient. Then, I want to calculate it multiple times as much as "I3" cell. After that, I want to write a code which finds max correlation coefficient from this calculation. I wrote the code below but it didn't work.
Sub Macro1()
Dim i As Long
For i = 1 To Range("I3")
Calculate
Next
DMax = Application.WorksheetFunction.Max("A2")
Range("I4").Value = DMax
End Sub
Any help is appreciated.
Your Max-Function needs a proper argument. Just typing "A2" doesn't work in VBA. Try:
DMax = Application.WorksheetFunction.Max(Range("A2"))
This will give you the max-Value of the Array A2. But keep in mind that the max-Value of a range consisting of a single cell is always the cell value.
If you want to calculate the maximum value of all iterations, you should use the max-function in each iteration (inside for-loop) and store it's value. In each following iteration you should then overwrite the max-Value if your new max value is larger than the old one. Just like this:
Sub Macro1()
Dim i As Long
DMax = 0
For i = 1 To Range("I3")
Calculate
DMax2 = Application.WorksheetFunction.Max(Range(...))
If DMax2 > DMax Then DMax = DMax2
Next i
Range("I4").Value = DMax
This will give you the max-Value of Range(...) of all iterations.
I barely understand your code, but the solution will be nasted loop. Suppose you have two sets of numbers: A2 (Cells(2, 1)) through I2 (Cells(2, 7)) and A3 (Cells(3, 1)) through I3 (Cells(3, 7)). You want to calculate partial correlation and find what was the maximum value of it.
For i = 1 To 7
For j = 1 To i
'Calculate the correlation
Next j
'here you have partial coefficient and you can compare it,
'if it is greater than previous one then save it and store
Next i
For i = 1 To Range("I3").value 'to calculate from 1 to the value in that cell
what i would recommend for your question.
For i = 1 To 10 ' loop 10 times
For j = 1 To i ' here it will allow you to check your stuff multiple times before moving on to the next value
arr1(i) = arr2(j) ' see if your array match
Next j
Next i
I have created a simple module that is meant to do following:
generate random number between 0 and 999;
if number is lower than 500, assign value "lower", otherwise "higher"
write the random number and assigned value in cells A1 and B1
repeat the process 100,000 times.
Problem is, it returns assigned value "lower" even if the number is higher than or equal to 500, i.e., all assigned values, 100,000 of them, are "lower"!
I'd appreciate if someone can check where I'm going wrong with this code; I'm not an expert in VBA, but I thought I could do this myself... :\
Sub MacroRanNum()
Dim RunNum As Integer
Dim Outcome As String
For i = 1 To 100000
Randomize
RanNum = Int((999 - 0 + 1) * Rnd + 0)
If RunNum < 500 Then
Outcome = "Lower"
ElseIf RunNum >= 500 Then
Outcome = "Higher"
Else
Outcome = "Error!"
End If
Sheets("podatak").Cells(i, 1) = RanNum
Sheets("podatak").Cells(i, 2) = Outcome
Next i
End Sub
Your variable name is RanNum but you check for RunNum
OPTION EXPLICIT could help to avoid such problems.
You are mixing your variable names. You define and check against RunNum but your random value and your display value are RanNum. You are never testing against the value you randomly generated.
I have a vb6 function that will take up to 7 numbers, order them, find a common difference. There will be a gap in this sequence of numbers. I also want to identify the missing number.
Example input is 19,17,20,and 16. The output should be an array 16,17,18,19,20 in this order. Any help? I may be able to interpret vb.net code to vb6, but vb6 is preferred to me.
Here’s an outline of what needs to be done:
Find the smallest and largest number
Create an array with enough entries to hold the full range from the smallest to largest
Fill the array with the numbers from lowest to highest.
Note that you don’t need to sort the numbers at all. You just need to find the extreme values.
Here’s a code outline in VB6:
Function RangeFrom(ParamArray Numbers() As Long) As Long()
Dim Lowest As Long
Dim Highest As Long
Lowest = Numbers(0)
Highest = Numbers(0)
Dim Number As Long
For Each Number In Numbers
If Number < Lowest Then Lowest = Number
If Number > Highest Then Highest = Number
Next
Dim Result(0 To Highest - Lowest) As Long
Dim I As Long
For I = 0 To Highest - Lowest
Result(I) = Lowest + I
Next
FromRange = Result
End Function
Since you have tagged VB.NET as well, this should be convertible to VB6(i've avoided Linq):
Public Shared Function FillGaps(input As Int32()) As Int32()
Dim output = New List(Of Int32)
Array.Sort(input)
' now we'll find the min/max-values at the first/last indices
For i As Int32 = input(0) To input(input.Length - 1)
output.Add(i)
Next
Return output.ToArray()
End Function
Use it in the following way :
Dim intArray = {19, 17, 20, 16}
intArray = FillGaps(intArray)
Note that this approach skips duplicates.
I am trying to work with taking in and parsing CSV files. Right now I have it taking in and producing something like this:
The program loads the csv and copies the data into an array as such:
ReDim strarray(num_rows, num_cols)
For x = 0 To num_rows
strline = strlines(x).Split(",")
For y = 0 To num_cols
strarray(x, y) = strline(y)
Next
Next
The CSV file data is very basic formatted with two columns and x number of rows:
212, 343
324, 232
etc. I guess my main problem is trying to perform calculations to all values in a specific column. To start I am just trying to figure out how to isolate the columns and found that by using MsgBox(strarray(x, num_cols)) it will msgbox everything in the second column twice. I just want to try and understand how I can perform a basic calculation like multiply every value in the first column by 2 and every value in the second column one by 3.
To start with: In VB arrays go from 0 to number of items minus 1. However you will have specify the maximum index, not the size:
Dim x As String() = new String(N-1) 'Where N is the number of items.
Dim y As String() = new String(MAX) 'Where MAX is the highest index.
And you have integer numbers. So you would have to declare:
Dim matrix As Integer(,) = new Integer(num_rows-1, num_cols-1)
And then fill it with:
For row As Integer = 0 To num_rows-1
Dim strline As String() = strlines(row).Split(",")
For col As Integer = 0 To num_cols-1
matrix(row, col) = Integer.Parse(strline(col))
Next
Next
Example calculation:
For row As Integer = 0 To num_rows-1
matrix(row,0) *= 2
matrix(row,1) *= 3
Next