1. IE 8580 Module 4: DIY Monte Carlo Simulation
Lecture 4.3:
Visual Basic for Applications 102

2. More detailed steps Add a module Start the sub Project Explorer
Highlight the Excel file
Insert > Module
Start the sub
In Code window, type Sub LoopIt <Enter>
() and End Sub are added automatically
IE 8580,

3. Write the Following Program
Notice the blue for the reserved words
IE 8580,

4. Create a button in Excel
Go back to Excel
Developer Tab
Click Insert
Click the button symbol
Draw button
Assign Macro Dialog Box opens
Select the macro we created, click OK
Click the button while still selected to change text
Unselect the button
Click it to run
To reselect the button, right click the button then left click
IE 8580,

5. Declaring Variables Declare all variables Use Dim keyword Basic Types
Whole Numbers: Integer (-32,768 to 32,768), Long (more than Integer)
Real Numbers: Single, Double
String, Boolean, Currency, Variant
Objects
If you try to assign a value out of the allowable range, you will get an OVERFLOW error
IE 8580,

6. Syntax for Declaring Variables
Basic syntax
Dim varname As type
Multiple variables on a line
Dim i As Integer, j As Integer, k As Integer
Variables get values using the equal sign assignment
i = 1
IE 8580,

7. The ampersand (&) concatenates the information
Message Boxes
Most basic syntax
MsgBox “stuff for the box”
MsgBox “the value of the variable is ” & varname
The ampersand (&) concatenates the information
Be careful with spaces!!!
IE 8580,

8. If condition then do_something Else do_something_else End if
Basic If Syntax
If condition then do_something
If condition then do_something
Else
do_something_else
End if
IE 8580,

9. If condition then do_something Else do_something_else End if
Basic If Syntax
If condition then do_something
If condition then do_something
Else
do_something_else
End if
Statements can be multiple lines
Indentation helps readability
VBA does some indention for you
I love tabs
IE 8580,

10. If condition then do_something Else do_something_else End if
Basic If Syntax
If condition then do_something
If condition then do_something
Else
do_something_else
End if
The “else” clause
is optional
IE 8580,

11. If condition then do_something Else do_something_else End if
Basic If Syntax
If condition then do_something
If condition then do_something
Else
do_something_else
End if
The “else” clause
is optional
IE 8580,

12. If-then-elseif Constructions
If condition1 then do_something1
Elseif condition2
do_something2
Elseif …
Else
do_default
End if
IE 8580,

13. For repeating a statement or series of statement over and over again
Looping
For repeating a statement or series of statement over and over again
Definite (pre-determined) number of repetitions: use a for loop
Indefinite number of repetitions:
Repeat some code while some condition holds: use one of the four do (or while) loop structures
IE 8580,

14. For counter = first To last [Step increment] statements Next [counter]
For Loops
first, last and increment are often integers (positive or negative, increment is not 0)
Using the counter in the Next statement
Helps readability
Required for nested for loops
For counter = first To last [Step increment]
statements
Next [counter]
IE 8580,

15. Check If You Are Following Me!
Write a sub that
requests a positive integer between 10 and 20 (assume it is correctly entered)
Display each odd number from one to entered integer in ONE messagebox (build the message in a string then display it)
IE 8580,

16. Answer for the Check
IE 8580,