Hello,
Im trying to design a module in which, using an equation, x and y coordinates are found and i want to display them in a list box.
The general idea in my mind is that the program asks the user to enter the length and number of divisions (lets suppose length is 1 and divisons are 1000) so 1 divided by 1000 equals 0.001, that is i want the value of x, starting from 0 then 0.001 then 0.002 then 0.003 and so on till 1 and its corresponding value of y and adding it simultaneously to the list box by using the for loop. I generally work on c++ but my project is on vb so im kinda having trouble. The result is that the textbox prints only two values of x that are 0 and 1. Here's the code. Would really appreciate the help.

Public Class Form9

    Private Sub Button1_Click(sender As System.Object, e As System.EventArgs) Handles Button1.Click
        Dim n1 As Integer
        Dim n2 As Integer
        Dim n3 As Integer
        Dim div As Integer = 0
        Dim lenght As Double = 0.0
        Dim t As Double = n3 / 100
        Dim x As Double =length / div
        If TextBox1.Text <> "" And TextBox2.Text <> "" And TextBox2.Text <> "" And TextBox3.Text <> "" And TextBox4.Text <> "" And TextBox5.Text <> "" Then
            n1 = CDbl(TextBox1.Text)
            n2 = CDbl(TextBox4.Text)
            n3 = CDbl(TextBox5.Text)
            num = CDbl(TextBox2.Text)
            chord = CDbl(TextBox3.Text)
            For x = 0 To length
                Dim y As Double = (((t / 0.2) * length) * ((0.2969 * (Math.Sqrt(x / length))) - (0.126 * (x / length)) - (0.3516 * ((x / length) ^ 2)) + (0.2843 * ((x / length) ^ 3)) - (0.1015 * ((x / length) ^ 4))))
                ListBox1.Items.Add(x)
            Next x
        End If
    End Sub
End Class

Thank You

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sorry the chord is supposed to be length

I see you are assigning the value to Y but you are adding X to the list box.

Dim y As Double = (((t / 0.2) * length) * ((0.2969 * (Math.Sqrt(x / length))) - (0.126 * (x / length)) - (0.3516 * ((x / length) ^ 2)) + (0.2843 * ((x / length) ^ 3)) - (0.1015 * ((x / length) ^ 4))))
ListBox1.Items.Add(x)

i was just testing out how the list box works. thats why i just assigned x and it showed only 0 and 1 and when i pressed the button again it showed 0011

i want the values of x to vary by length/div in every loop.
what can be the syntax of that?

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