1. ChE 117 Motivation Lots of Tools Can’t always use “Canned Programs”
Excel • Mathematica
MathCAD • Calculators
Matlab • Polymath
Can’t always use “Canned Programs”
i.e. binary phase equilibria
Data manipulation
Process control and data acquisition
Excel macro language (VBA)
Web pages

2. Programming language: Visual Basic
Interface with Excel (VBA)
Similar to Fortran, C, C++, etc
PC-based DAQ (data acquisition) and control
High-level language (vs assembly)
What is: Visual Basic .NET
Computer interface
List of instructions
Contains Interpreter
VB  machine language “on the fly”

3. Example: convert °F to °C or °C to °F
What is a Program?
Road map
Set of instructions
Good for repetition
Input 
Manipulate
Output
Example: convert °F to °C or °C to °F
GUI
ID Parts!

4. Example Program (manipulation)
Average 3 numbers (10, 12, 15)
Sub Avg()
n1 = 10
n2 = 12
n3 = 15
avge = (n1 + n2 + n3) / 3
MsgBox avge
End Sub

5. Decisions (“If” statements)
Sub test2()
label = "F"
TF = 212
If label = "F" Then
TC = (TF + 460) /
MsgBox TC
End If
End Sub
“If – Then – Else - Endif
Sub test3()
label = "C"
Tin = 100
If label = "F" Then
Tout = (Tin + 460) /
Else
Tout = (Tin + 273) *
End If
MsgBox Tout
End Sub

6. Loops (“If” statements) Add numbers 1 - 10
Sub looper1()
sum = 1
n = 1
10 If n < 10 Then
n = n + 1
sum = sum + n
GoTo 10
End If
MsgBox sum
End Sub
Loops (For – Next)
Sub looper2()
sum = 0
For i = 1 To 10
sum = sum + i
Next i
MsgBox sum
End Sub

7. MS Excel & Visual Basic (VBA ~ VB.6)
Excel Environment
Worksheets
Chart Sheets
Workbook
Modules
sub & function procedures
User Forms
and objects
(VBA code)
VB Editor / Modules

8. Example Program (manipulation)
Set up macro to calculate an average… use example as template.
Run the macro
Set up Form Button to run macro

9. Problem Solving Exercise (in groups)
Set up macro to convert 100 kg to lbs or lbs to kg
Display result in msgbox
Run the macro
Set up Form Button to run macro