IE 8580 Module 4:DIY Monte Carlo Simulation

Lecture 4.1:Visual Basic for Applications 101

Visual Basic Editor

• The Visual Basic Editor (VBE) is the environment in which you work with VBA programming code.– ALT + F11

• VB Developer Tab– Add it through the Excel Options– Click Visual Basic

Scott J. Mason, Ph.D., mason@clemson.edu

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Visual Basic Editor

• Code is saved in a .xlsm file– Clicking Save in VB Editor or Excel saves both the Excel file

and the VB code

Scott J. Mason, Ph.D., mason@clemson.edu

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Fix Security Settings

• On the Developer Tab, click Macro Security• Click Disable all macros with notification

Scott J. Mason, Ph.D., mason@clemson.edu

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When opening a .xlsm file

• When you see the message below, Enable Content, assuming you know/trust the source of the file!

IE 8580, mason@clemson.edu

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Record Your Own Macro

• Developer Tab• Click Record Macro

– This is how I “learned” to write code when I was kid

• You can assign a hot key to run this macro (e.g., j)

Scott J. Mason, Ph.D., mason@clemson.edu

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Relative/Absolute References

• Relative References On

Scott J. Mason, Ph.D., mason@clemson.edu

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• Relative References Off– Absolute References

Example: Relative References Off

• Record Macro with relative references off– Create a spreadsheet with the text entries as follows, then click Record Macro

• Insert two rows below “Monday”• Move “Robert” cell below “Monday”• Move “Register” cell below “Robert”• Select the cell directly below• Click Stop Recording

Scott J. Mason, Ph.D., mason@clemson.edu

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Example: Relative References Off

• When the macro runs, two rows are inserted below “Monday” again instead of below “Tuesday”

• The rows are always inserted between rows 1 and 2 and cells B1 and C1 are always moved

Scott J. Mason, Ph.D., mason@clemson.edu

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Example: Relative References Off

• The VBA code:

Scott J. Mason, Ph.D., mason@clemson.edu

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Example: Relative References On

• Record the same Macro with Use Relative References on, then click Stop Recording

• Now the starting cell moves when the macro runs

Scott J. Mason, Ph.D., mason@clemson.edu

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Example: Relative References On

• The VBA code:

• Notice– ActiveCell.Offset([#rows],[#cols]) vs. Range(”B1”)

Scott J. Mason, Ph.D., mason@clemson.edu

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General Steps for Writing a Program

• Get into VB Editor• Add a module• Write a sub (or copy it in this case)• Run the code from VB Editor• Optional (but useful): Add a button to the

spreadsheet to run the code

• We’ll revisit this later in this module!

IE 8580, mason@clemson.edu

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