VB程序设计 在坐标系上用Line方法绘制

第三条没怎么看懂
Const PI = 3.14159
Dim i As Single
Picture1.Scale (-2 * PI, 2)-(2 * PI, -2)
Picture1.Line (-2 * PI, 0)-(2 * PI, 0)
Picture1.Line (0, -2)-(0, 2)
For i = -2 * PI To 2 * PI Step 0.5
Picture1.CurrentX = i
Picture1.CurrentY = 0
Picture1.Line -(i, 0.05)

Next

For i = -2 To 2 Step 0.5
Picture1.CurrentX = 0
Picture1.CurrentY = i
Picture1.Line -(0.1, i)
Next

'==================正弦曲线===================
Picture1.CurrentX = -2 * PI
Picture1.CurrentY = 0
For i = -2 * PI To 2 * PI Step 0.01
Picture1.Line -(i, Sin(i))
Next