How to plot array in VBA? - arrays

Question

I want to create a function plot_array(arr As Variant) which will create plot based on element in array.
On x axis I want to have numbers 1, 2,.., n which are indexes of array elements, and on y axis I want to have values stored in array. In other words
Example
Dim arr(9) As Variant
arr(0) = 0
arr(1) = 1
arr(2) = 5
arr(3) = 1
arr(4) = 5
arr(5) = 5
arr(6) = 1
arr(7) = 7
arr(8) = 6
plot_array(arr)
I tried to figure it about by running Macros and thinking how can I generalize this code to be working for any array, but I end up with nothing. Is there any possibility how it can be done ?

Answer 1

Try the next code, please. It will create a chart (xlLine type) and feed it with the array. You can change in the line .SeriesCollection.NewSeries.Values = arr1 arr1 with arr and obtain the same thing, if you put all the used number in the range "A1:A9":
Sub testPlotChartArray()
Dim sh As Worksheet, cH As Chart, arr1, arr(1 To 9)
Set sh = ActiveSheet
arr1 = sh.Range("A1:A9").Value
arr(1) = 0: arr(2) = 1: arr(3) = 5: arr(4) = 1: arr(5) = 5
arr(6) = 5: arr(7) = 1: arr(8) = 7: arr(9) = 6
On Error Resume Next
Set cH = sh.ChartObjects("PlotChart").Chart
If Err.Number = 0 Then
Err.Clear
cH.Parent.Delete
End If
On Error GoTo 0
Set cH = sh.ChartObjects.Add(left:=60, top:=10, width:=300, height:=300).Chart
With cH
.Parent.Name = "PlotChart"
.ChartType = xlLine
.SeriesCollection.NewSeries.Values = arr1 'or arr
End With
End Sub
The above code deletes the chart if it exists, but it can be configured to use the same existing chart and feed its .SeriesCollection(1).Values...

Answer 2

If you declare an array as arr(9) in Excel, the index is declared as a total of 10 arrays from 0 to 9, so your array is not the correct number.
Sub test()
Dim arr(8) As Variant
arr(0) = 0
arr(1) = 1
arr(2) = 5
arr(3) = 1
arr(4) = 5
arr(5) = 5
arr(6) = 1
arr(7) = 7
arr(8) = 6
plot_array (arr)
End Sub
Sub plot_array(arr As Variant)
Dim Srs As Series
Dim Cht As Chart
Dim xAxes As Axis, yAxes As Axis
Dim i As Integer, vX() As Variant
ReDim vX(LBound(arr) To UBound(arr))
For i = LBound(arr) To UBound(arr)
vX(i) = i + 1 '<~~ if index start from 0 then delete +1
Next i
Set Cht = ActiveSheet.Shapes.AddChart.Chart
With Cht
.HasTitle = True
.ChartTitle.Text = "My Graph"
.ChartType = xlXYScatterLinesNoMarkers
For Each Srs In .SeriesCollection
Srs.Delete
Next Srs
Set Srs = .SeriesCollection.NewSeries
With Srs
.Name = "item"
.Values = arr
.XValues = vX
.MarkerStyle = xlCircle
End With
Set xAxes = .Axes(xlCategory, xlPrimary)
With xAxes
.MinimumScale = 0
.MaximumScale = WorksheetFunction.Max(vX)
.MajorUnit = 1
.HasMajorGridlines = True
End With
Set yAxes = .Axes(xlValue, xlPrimary)
With yAxes
.MinimumScale = 0
.MaximumScale = WorksheetFunction.Max(arr) + 1
.MajorUnit = 1
.HasMajorGridlines = True
End With
End With
End Sub