For X = -10 To 10 Step 0.05 TmpStr = Replace(Ucase$(MathStr), "X", X) '替换掉原公式中的值 Y = ScriptControl1.Eval(TmpStr) '根据表达式计算值. '坐标原点是500,500 Picture1.CurrentX = 1000 + X * 15 Picture1.CurrentY = 3000 - Y * 15 '注意,电脑的Y坐标与数学坐标是相反的. Picture1.Print "." Next End Sub
Private Sub Command1_Click()
Dim MathStr As String
Dim TmpStr As String
On Error Resume next
MathStr = "2*(X^2)+3*(X)+23" '定义一个数学函数,可以能过TEXTBOX输入,但是只能有一个变量X.还要注意调整下面FOR循环中的范围.例如:1/X.要保证X>0.
For X = -10 To 10 Step 0.05
TmpStr = Replace(Ucase$(MathStr), "X", X) '替换掉原公式中的值
Y = ScriptControl1.Eval(TmpStr) '根据表达式计算值.
'坐标原点是500,500
Picture1.CurrentX = 1000 + X * 15
Picture1.CurrentY = 3000 - Y * 15 '注意,电脑的Y坐标与数学坐标是相反的.
Picture1.Print "."
Next
End Sub