split the code while argument is not affected

Your functions are not connected to each other, nor are they currently open to feeding parameters one to another.

Function abc(op1 As Double, op2 As Double, _
Figure_1 As Long, Figure_2 As Long)

Dim p1 As Variant, p2 As Variant, p As Variant

op1 = 100 'input for user define function
op2 = 100 'input for user define function
Figure_1 = 1 'input for user define function
Figure_2 = 2 'input for user define function

abc = p1 + p2

End Function

In this function you are setting abc = to p1 +p2, but in the code above that in the function there is no code to give values to P1 or P2. So you are adding 0 + 0. You'll need to use INDEX100 to resolve p1 & P2 first.

I've merged that into one function that would appear to do the correct thing:

Function abc(op1 As Double, op2 As Double, Figure_1 As Long, Figure_2 As Long)

op1 = 100 'input for user define function
op2 = 100 'input for user define function
Figure_1 = 1 'input for user define function
Figure_2 = 2 'input for user define function

If op1 >= 100 Or op2 >= 100 Then abc = Figure_1 + Figure_2

End Function

I'm assuming the lines in red will actually be removed and you will use the function to feed in the 4 parameters via cell reference.

How long was the procedure too large?

When creating a function, the parameters in the () denote the values that will be used in the function. When calling that function from another function, be sure to insert those parameters into the call, the same way you fill out a formula's parameters as you enter it into a cell.


In your original code above, the INDEX100 could be used to bring back a single result. But it looks like you need results to resolve the values of P1 and P2. I would suggest creating functions for those.

Here's a very simple example of what I mean. Here I've created a GetP1 and a GetP2 function, within those functions you can do whatever routines you need, but the end result is a single value fed back as the result of GetP1. In the main macro, that result is stored into a variable and used as needed.

Option Explicit

Function abc(op1 As Double, op2 As Double, Figure_1 As Long, Figure_2 As Long)
Dim p1 As Long, p2 As Long, p As Long

p1 = GetP1(op1, Figure_1, Figure_2)
p2 = GetP2(op2, Figure_1, Figure_2)

abc = p1 + p2

End Function

Private Function GetP1(Op1 As Double, Figure_1 As Long, Figure_2 As Long) As Long

    If op1 >= 300 Then
        GetP1 = Figure_1 + Figure_2
    ElseIf op1 >= 200 Then
        GetP1 = Figure_1
    ElseIf op1 >= 100 Then
        GetP1 = Figure_2
    Else
        GetP1 = Figure_1 - Figure_2
    End If

End Function

Private Function GetP2(Op2 As Double, Figure_1 As Long, Figure_2 As Long) As Long

    If op2 >= 300 Then
        GetP2 = Figure_1 + Figure_2
    ElseIf op2 >= 200 Then
        GetP2 = Figure_1
    ElseIf op2 >= 100 Then
        GetP1 = Figure_2 * 3
    Else
        GetP2 = Figure_1 / Figure_2
    End If

End Function

my code is over 64 kb in a single function without code splitting,that why the error pop out.

that what i am looking for,thank you very much.