10/10/2005 BAE 1012111

Spreadsheet Macros(Visual Basic for Applications)

Slides to accompany an in-class demo of spreadsheet technique:

Macro Programming

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Creating and Editingan initial Macro

• Select TOOLS/MACRO/RECORD

– This will create a VBA (Visual BASIC for Applications) subroutine shell

• Be sure to set the shortcut for executing the macro

• You may immediately STOP recording or use the recording to create part or all of a macro

• To Edit an existing Macro, select TOOLS/MACRO/MACROS…

– Select the Macro by Name• The VBA Programming environment will be selected.

• You may fill in VBA programming between the start and end.

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Creating a Macro toInsert an OSU Logo

• Record a Macro• Set the recorder to “relative”

– Later when run the macro will produce results relative to the starting position

• ctrl-i as shortcut

• OSU_LOGO as Name

• Type and Format text• Type: OSU into A1

• Format as:– Goudy Old Style– 36 pt.– Bold– Color = orange– Cell background = Black

• Test macro by typing ctl-i

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Creating a Macro toInsert an OSU Logo

• Draw Triangle in “O”– Enable Drawing Toolbar VIEW/TOOLBARS/Drawing

– Select and place Triangle• Autoshapes/Basic Shapes/Isosceles Triangle

• Drag triangle to position

• Stop Recording• Test the Macro• Modify or Edit to correct errors

10/10/2005 BAE 1012511

Creating a Macro toAdd a Function to Excel

• Functions– Definition:

• A program that when executed returns a value

– Example• The “sum” function when inserted in a cell returns the value of the

specified sum

– User defined functions• Spreadsheets typically allow user defined functions to be created

• Procedure– Open the Visual Basic Editor– Select INSERT/PROCEDURE

– Select Function– Enter the function Name

– Edit the function– To test, insert the function into a cell in a spreadsheet

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Example Function

Public Function headloss(f, l, d, v)'' Function Headloss' This function computes headloss in a pipe given the following parameters' f - Friction Factor' l - Pipe length' d - Pipe diameter' v - Fluid velocity' Units should be consistent (all metric or all english and compatible

headloss = f * (l / d) * ((v * v) / (2 * 9.81))End Function

Variable must be the same as function name

Input variables

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To Access or Write Cell Values

• Within a procedure or function– To write “x” into a cell, use the following syntax:

• Worksheets("Sheet1").Cells(i, j).Value = x– Where Sheet1 is the worksheet title– i is the row of the cell– j is the column of the cell

– To read a cell value into “x”, use the following syntax:• x = Worksheets("Sheet1").Cells(i, j).Value

– Where Sheet1 is the worksheet title– i is the row of the cell– j is the column of the cell

• In the above example– Worksheet is an object– .Cells is a property– .Value is a property of a property– The properties of an object can be set.

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Visual Basic Language Elements

• Loop (For/Next)– For i = 1 to 100 step 4

• Begins a loop which increments i by 4 each time

• 1 is the initial value for i

• 100 is the final value for i

– Next i• Ends the loop of which i is the index

• i is tested at the end and if greater than or equal to 100 the loop ends

Example:

For i = 1 To 12 Worksheets("Sheet1").Cells(i, 5).Value = iNext i

Writes 12 values into worksheet cells in E1:E12, (column 5 = column E)

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Visual Basic Language Elements

• Conditional Test (IF)– IF (condition) THEN (True clause) ELSE (False clause) ENDIF

• Example: IF x<5 THEN x=5 ELSE x=0

• Example: IF x<5 THEN x=5

• ENDIF is used for multiple line clauses

– Conditional operators:– Less than <, greater than >– Less than or equal <=, greater than or equal >=– Not equal <>

For i = 2 To 12 IF i = 6 THEN Worksheets("Sheet1").Cells(i, 5).Value = "SIX” Else Worksheets("Sheet1").Cells(i, 5).Value = I ENDIFNext i

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Objects and Properties

• Elements that may be referenced are:– Objects (Cells, Worksheets, ChartTitle, etc.)

• Can contain properties, methods, other objects– Properties (Value, Size, etc.)– Methods (Clear, Copy, etc.)

• Property Reference example:• Font.Size = 9 - Font is an object, size is a property

• Method example• Worksheet(“sheet1”).Range(“a1:c3”).Copy

• Worksheet and Range are objects, Copy is a method

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Relative references in Macros

• Regarding relative or absolute in macro recording– The references to movement recorded within a macro can be

absolute cell references or relative to starting position• Relative or absolute is toggled with the icon button provided with

the start/stop button for macro recording