How to change picturebox coordinate system?

Public Class Form1

    'Declare variables
    '-----------------------------------------------------
    Private Structure PointType
        Dim X As Double
        Dim Y As Double
    End Structure


    Dim Reg As New RegressionObject
    Private LastEndPoint As New Point(0, 0)

    'Graph lines and points
    Dim regLine As New Series
    Dim points As New Series

    'The radius
    Const R = 100

    'Point
    Dim P(0 To 200) As PointType

    'Array that holds X and Y values for graphing
    Dim MyData() As Single = New Single() {69400, 2500, 109000, 5000, 207900, 7500, 297200, 10000, 346500, 12500}

    'Scale graph to stay within the picturebox
    Dim HorizontalScaleFactor As Single

    'The array for the points on the graph
    Dim DataPoints(MyData.Length - 1) As PointF

    'Points where the number labels are drawn
    Dim labels As PointF

    'The font
    Dim drawFont As New Font("Arial", 16)
    Dim cordFont As New Font("Arial", 8)

    'Regression degrees
    Dim deg As Integer

    Dim flag As Boolean
    Dim loaded As Boolean

    'FORM LOAD
    Private Sub Form1_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load

        For i As Integer = 1 To 10
            degBox.Items.Add(i)
        Next
        loaded = False
        flag = False
        degBox.Text = "3"
        Reg.Degree = deg
    End Sub



    'This updates the picturebox everytime it is redrawn
    Private Sub picboxPulseCurve_Paint(ByVal sender As Object, ByVal e As System.Windows.Forms.PaintEventArgs) Handles picboxPulseCurve.Paint

        Dim i As Integer

        e.Graphics.SmoothingMode = Drawing2D.SmoothingMode.HighQuality
        'e.Graphics.DrawCure(ve(Pens.Blue, DataPoints))
        regLine.Name = "Regression Curve"
        regLine.ChartType = SeriesChartType.Spline
        regLine.Color = Color.Maroon
        With Reg
            Using pn As New Pen(Color.Red, 2)
                For i = 0 To .XYCount
                    DrawACircle(e, pn, New Point(P(i).X, P(i).Y), R / 10)
                Next i
            End Using

            LastEndPoint = New Point(0, .RegVal(CDbl(Me.ClientRectangle.Height)))
            Dim CurrentPoint As Point
            For i = 0 To Me.ClientRectangle.Width Step R
                CurrentPoint = New Point(i, .RegVal(CDbl(i)))
                Using pn As New Pen(Color.BlueViolet, 3)
                    e.Graphics.DrawLine(pn, LastEndPoint, CurrentPoint)
                End Using
                e.Graphics.DrawLine(Pens.Red, 0, MyData.Max + 150, 0, 0)
                e.Graphics.DrawLine(Pens.Red, MyData.Max + 150, 0, 0, 0)
                If (flag = False) Then
                    regLine.Points.AddXY(-CurrentPoint.X, -CurrentPoint.Y)
                End If
                LastEndPoint = CurrentPoint
            Next i
            If (flag = False) Then
                graph.Series.Add(regLine)
                graph.Series.Add(points)
            End If
        End With
    End Sub

    'Draws a circle at the given points
    Private Sub DrawACircle(ByVal e As System.Windows.Forms.PaintEventArgs, ByVal P As Pen, ByVal center As Point, ByVal radius As Integer)
        ' Create a bounding rectangle and make its center the center of our point
        ' Then make its width 2 * the radius
        ' Then draw our ellipse
        points.Name = "Points"
        points.ChartType = SeriesChartType.Point
        points.Color = Color.Black
        Dim rect As New Rectangle(center, New Size(0, 0))

        For i = -3000 To MyData.Max + 150 Step 50
            labels = New Point(i, 0)
            e.Graphics.DrawString(i.ToString(), drawFont, Brushes.Black, labels)
            e.Graphics.DrawLine(Pens.Black, i, 0, i, MyData.Max + 150)
        Next

        For i = -3000 To MyData.Max + 150 Step 50
            labels = New Point(0, i)
            e.Graphics.DrawString(i.ToString(), drawFont, Brushes.Black, labels)
            e.Graphics.DrawLine(Pens.Black, 0, i, MyData.Max + 150, i)
        Next

        rect.Inflate(radius, radius)
        e.Graphics.DrawEllipse(P, rect)
        e.Graphics.DrawString(center.X.ToString() + " " + center.Y.ToString(), cordFont, Brushes.Black, New PointF(center.X + 8, center.Y))
        If (flag = False) Then
            points.Points.AddXY(-center.X, -center.Y)
        End If
    End Sub


    'This button resets the graphs and data
    Private Sub resetBtn_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles resetBtn.Click
        flag = False
        regLine.Points.Clear()
        points.Points.Clear()
        graph.Series.Clear()
        txtBox.ResetText()
        Reg.Init()

        MsgBox("Data has been reset!")
    End Sub


    'This populates the program with graph points that are loaded from a file
    'It also resets the graphs and data
    Private Sub PopulateDataPointsArray(ByVal PictureBoxWidth As Integer)
        'Scale the graph to fit the picture box:
        HorizontalScaleFactor = CSng(PictureBoxWidth / DataPoints.Length)
        picboxPulseCurve.Width = MyData.Max + 150
        picboxPulseCurve.Height = MyData.Max + 150

        If (flag = False) Then

            regLine.Points.Clear()
            points.Points.Clear()
            graph.Series.Clear()
        End If
        txtBox.ResetText()
        Reg.Init()

        'Populate the DataPoints array:
        For i As Integer = 0 To DataPoints.Length - 2
            DataPoints(i).X = MyData(i)
            DataPoints(i).Y = MyData(i + 1)

            txtBox.Text += ("X: " + MyData(i).ToString() + " Y: " + MyData(i + 1).ToString() + vbNewLine)


            With Reg
                .XYAdd(DataPoints(i).X, DataPoints(i).Y)
                P(.XYCount).X = DataPoints(i).X
                P(.XYCount).Y = DataPoints(i).Y
            End With

        Next

        Me.Refresh()

    End Sub

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