用VB 画抛物线
Private Sub Command1_Click()
Dim X, Y As Single
For X = -5 To 5 Step 0.0001
Y = 3 * X * X + 2 * X + 1
Picture1.PSet (X, Y), vbBlack
Next X
End Sub
Private Sub Command2_Click()
Picture1.DrawWidth = 2
Picture1.Line (-5, 0)-(5, 0)
Picture1.Line (4.7, 0.1)-(5, 0)
Picture1.Line (4.7, -0.1)-(5, 0)
Picture1.Line (0, -5)-(0, 5)
Picture1.Line (-0.1, 4.7)-(0, 5)
Picture1.Line (0.1, 4.7)-(0, 5)
Picture1.DrawWidth = 1
For i = -4.8 To 4.8 Step 0.2
Picture1.Line (i, 0.2)-(i, 0), vbBlack
Next i
For i = -4.8 To 4.8 Step 0.2
Picture1.Line (0.1, i)-(0, i), vbBlack
Next i
Picture1.CurrentX = 0.25
Picture1.CurrentY = -0.25
Picture1.Print "O"
Picture1.CurrentX = 4.7
Picture1.CurrentY = -0.25
Picture1.Print "X"
Picture1.CurrentY = 4.7
Picture1.CurrentX = -0.25
Picture1.Print "Y"
End Sub
Private Sub Form_Load()
Picture1.Scale (-6, 6)-(6, -6)
End Sub
Private Sub Picture1_MouseMove(Button As Integer, Shift As Integer, X As Single, Y As Single) Label1.Caption = "坐标" & X & "," & Y
End Sub