Lecture 1 Introduction

1
Lecture 1 - Introduction

• August 27, 2001
• CVEN 302

2
Lectures Goals

• General Introduction to CVEN 302 - Computer
  Applications in Engineering and Construction
• Introduction to Computer Lab
• Why do you need to be able to write and
  understand computer program and numerical
  methods?
• Matlab - Mathematical Laboratory

3
CVEN 302 Computer Applications in Engineering
and Construction

• Text Applied Numerical Analysis
• Using MatLab
• Author Laurene V. Fausett
• Software Matlab Version 6.0

4
Introduction

• Professor Dr. E. Sandt
• Office 207 CVEN Building
• Phone [phone]
• Office Hr M-F 200 PM - 400 PM
• Email esandt_at_stommel.tamu.edu
• URL http//stommel.tamu.edu/esandt/

5
Grade Breakdown

• Homework 20
• Exam 1 25
• Exam 2 25
• Final 30

6
Topics

• Matlab
• Computer Errors
• Roots f(x) 0
• Linear Methods
• Nonlinear Methods
• Linear Systems
• LU Decomposition
• Eigen Analysis

• Fitting Data
• Interpolation
• Curve Fitting
• Numerical Integration
• ODEs
• Initial Value Problems
• Systems of ODEs
• Boundary Value Problems

7
Why do we need to know how to use numerical
analysis and methods?

• You are not going to be given a nice neat
• exact solution in the real world.
• Applications
• Numerical Errors
• Computer Types
• Computer Software

8
Applications

• Signal Processing
• CFD (Computational Fluid Dynamics)
• Structural Analysis
• Finite Element Analysis

• Interpolation
• Optimization
• CAD (Computer Aided-Drafting)
• Data Collection

9
Numerical Errors

• Computers are only as good as the
• person running them.

10
Numerical Errors

• Precision Limits
• Stability
• Convergence
• Divergence
• Alaising

• Round-off Errors
• Truncation Errors
• Machine Precision

11
Computer Hardware Types

• Personal Computer
• Supercomputers
• Vector Processors
• Array Processors
• Parallel Processor

12
Software

• Operating Systems
• Windows - NT, ME, Windows
• Unix
• VMS - VAX
• Linux

13
Software

• Languages
• Fundamental Assembler (Bit manipulations)
• Engineering Languages
• Fortran
• Cobol
• Pascal
• C
• Basic
• HTML and Java

14
Software

• Higher-Order Programming
• Maple - Mathematical Programming Language
• Mathematica - Mathematical Programming Language
• Java - Internet Programming Language
• Matlab - Matrix Laboratory

15
Software

• Tools
• Word Processors
• Spreadsheets
• Database Management
• Graphics
• Mathematical Computer Codes

16
Matlab -Matrix Laboratory

• Currently Matlab 6.0 is available on CVEN
• Network
• 50 Licenses are available on the network with a
  wavelet tool box
• Student Version is available at the MSC (120)
  without the tool boxes.

17
MatLab

• You will need to obtain an account on the CVEN
  Network. You can obtain an account in the CVEN
  Lab. It will take a couple of days to get it
  setup.
• The Matlab program can be run using command line,
  batch commands, and programs.

18
What is a program?

• Program consist of three main components
• Input
• Main Program - Numerical methods and analysis
  and/or evaluation.
• Output - Results.

19
Inputs

• Numerical values
• Initialization of the variables
• Conditions
• Equations

20
Main Program

• Using flow charts, the programs can be designed
  to perform a task. Using
• Loops
• Conditions
• Error Convergence

21
Output

• Outputs are the results of the program. They can
  go through a series of post-processing methods.
• Numerical Values
• Decisions
• Graphs and Plots

22
MatLab

• Variable Types
• Integers
• Real Values (Float)
• Complex Numbers (a ib)
• a - real value
• b - imaginary value (i is the square root of
  -1)

23
Matlab

• Data types
• Numerical
• Scalars
• Vectors
• Matrices
• Logic Types
• Alpha/Numerical Types

24
Matlab

• A scalar value is the simple number, a, 2,
  3.14157,
• A vector is a union of a x (x1, x2, x3,
  x4)
• Transpose vector xT x1
  x2 x3 x4

25
Matlab

• Matrix is a combination of vectors and scalars.
  Scalar and vectors are subsets of matrices.
• Matlab uses matrix to do mathematical methods.

26
Matlab

• Set of computer functions
• Circular functions - sin(x),cos(x), tan(x),
  asin(x), acos(x), atan(x)
• Hyperbolic functions - sinh(x), cosh(x),
  tanh(x)
• Logarithmic functions - ln(x), log(x), exp(x)
• Logic functions - abs(x), real(x), imag(x)

27
Matlab

• Simple commands
• clc - clears window
• clg - clear graphic window
• clear - clears the workspace
• who - variable list
• whos - variable list with size
• help - when doubt use it!

28
Matlab

• Simple commands and symbols
• C - an escape from a loop
• inf - infinity
• NaN - No numerical value

29
Scalar Operations

• Addition - a b
• Subtraction - a - b
• Multiplication - a b
• Right Division - a / b
• Left Division - b \ a
• Exponential - ab

30
Order of Precedence of Arithmetic Operations

• Precedence
• ( 1 ) - Parenthesis
• ( 2 ) - Exponential from left to right
• ( 3 ) - Multiplication and division from left
  to right.
• ( 4 ) - Addition and subtraction from left to
  right.

31
Homework

• Obtain an account on CVEN Network
• Find the Website (http\\stommel.tamu.edu\esandt)
  
• Play with Matlab
• Email me and say Hi! I will need
  your email address to create an class email list.