425461%20MATLAB%20for%20Mechanical%20Engineering

1
425461 MATLAB for Mechanical Engineering

• ?. ???????????????????
• ?. ????? ???????
• Office Hour ??????, ???, ???????? 10.00 12.00
  ?.
• Email soradak_at_g.sut.ac.th ???????? 044-224399

2
425461 MATLAB for Mechanical Engineering

• ??????????????????
• ?????????????????? MATLAB ?????????
  ???????????????????????????????? MATLAB
  ???????????? M ???????????????????????????????????
  ???????????????????????????????
  ???????????????????????????????????
  ??????????????????????????????????????????????????
  ???????????? ?????????????????????????????????????
  ?????????????????? ????????????
  ??????????????????????? ??????????????????????????
  ?????????????????????? MATLAB ????????????????????
  ?????????

3
425461 MATLAB for Mechanical Engineering

• ??? ???? ????? ?????? ???? 17.00 - 20.00 ?.
  ???? CAD/CAM I (F5)
• ??????????????????
• ?????? MATLAB ????????????????? ??????? ?????
  ??????? ??? ?????? ????????????
• ??????????????
• 1 MATLAB ???????????????????????????
  ??????? ?????? ??????? ??????????
• 2 ??????????????? MATLAB ???????????
  ??????? ???? ??????????, ??????? ??????????

4
???????????????
?????????? ???????/??????
1 Introduction to MATLAB
2 MATLAB useful function
3 Writing MATLAB Function and Scripts
4 Branch and loop programming Functions and
5 I/O and file manipulation
Mid-term Mid-term
5
???????????????
?????????? ???????/??????
6 MATLAB Graphics Part 1
7 MATLAB Graphics Part 1
8 Polynomials and Fitting
9 Numerical integration and differentiation
10 Symbolic Mathematics
11 MATLAB for engineering problem Part 1
12 MATLAB for engineering problem Part 2
Final Final
6
????????????

• Class exam 20
• Quiz 20
• Mid-term 30
• Final 30
• ??? 100

7
??????????????????????? 1

• Introduction to MATLAB
• What is MATLAB?
• Introduction for using MATLAB
• Variable
• Exercises

8
What is MATLAB?

• The Language of Technological Computing
• A very fancy calculator
• A simple and user friendly programming language
• A tool for data analysis and statistics
• A tool to produce plots

9
Accessing MATLAB
10
Introduction for using MATLAB
11
The MATLAB Prompt

• gtgt denotes where you type commands
• Type or paste commands, then hit enter
• If entering multiple commands, separate them by
  semicolon ()
• Multiple commands may be on same line, as long as
  they are separated by semicolon ()
• Ending a command with also tells MATLAB to not
  display the output
• If want output displayed, do not use
• gtgt22
• ans
• 4
• gtgt

12
Variables

• Variables are the basic building blocks
• Capitalization matters, x not same as X
• Matrix is a variable that contains multiple
  entries, i.e. V.98 1.02 .99 1.07
• MATLAB is great with vectors and
  matrices,however, their orientation and size
  matter
• You will get errors if try to add vectors of
  different size or different orientation

13
Basic Operations

• Always use brackets to define matrices
• Always use prentices ( ) to call values of
  matrices
• The row is always first, the column is always
  second, i.e. M1(3,2) is not the same as M1(2,3)
• To see which variables exist, use gtgtwhos
• To delete variables, use gtgtclear x y
• To find out size use gtgtsize(M1)

14
(No Transcript)
15
Elementary Algebra

• Use , -, , / for basic operations
• Use ./ and . for element by element operations
  on matrices and vectors
• Use / and for matrix multiplication, but this
  only makes sense if youve taken Linear Algebra
• Use to transpose a matrix
• You can always multiply a matrix by a scalar
• You can always overwrite old variables

16
(No Transcript)
17
(No Transcript)
18
Ranges of numbers

• Colon specifies range of numbers
• gtgtV315 sets V3 to be the numbers 1 through 5
• gtgtV31313 sets V3 to be the numbers 1
  through 13, skipping every 3rd, note, it is
  transposed
• gtgtM5M1(12,15) sets M5 to be all the numbers in
  rows 1-2 and columns 1-5 of M1
• gtgtV3M1(,2) sets V3 to be the whole second
  column of M1

19
(No Transcript)
20
.m files

• .m files are just text files
• Do work in .m file
• Paste work into Matlab prompt
• Use to end lines
• Save .m files
• Use to add comments

21
Saving your work

• gtgtsave workspace1 x y saves the variables x and
  y in a file called workspace1.mat
• gtgtsave workspace1 saves all variables in
  workspace1.mat
• gtgtload workspace1 loads the variables in
  workspace1.mat
• gtgtclear all deletes all variables

22
Getting help

• gtgthelp lists topic areas, for example one of
  these is graph2d
• gtgthelp graph2d lists functions within graph2d,
  for example plot
• gtgthelp plot gives help on plot

23
Functions we learned

• General whos, clear, size, save
• Matrix zeros, ones, whos
• Math , -, , /,

24
Next week

• MATLAB Useful function