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:ommand windownter the Matlab statements after the>>rompt

ommandistorywindow

ork pacewindowurrentdirectoywindow

Appearance of the Matlab mainwindow

View or change the current working directory

:Prompt means theMatlab is ready to

accept commandfollowing the

.prompt

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Undocking of windows

,Click the undock button andthe command window will be

released from the group of.window

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Control of theappearance

Uncheck the option and the corresponding window will be

.turned off

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If start the Matlab with command option -nojvm ( :means no java virtual)machine

Another appearance of the Matlabwindow

Advantage : .The Matlab starts at a faster speed .The Matlab consumes less memory

,To leave Matlab either enter exit or quit or click on theX at the upper right corner of

.the Matlab window

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Some useful commands

/pwd cd

/ /dir mkdir rmdir /delete copyfile /who whos /what which /clear clc

MATLAB is -case sensitive - it differentiates between the.lowercase and uppercase letters Thus 'm' and 'M' are different

. -variables The built in commands and function in MATLAB are.typed in lowercase letters

/ / /help helpwin helpdesk doc

lookfordbtypedemo

Only the most fundamental usage of the commands will be presented.in the following slides Consult with the online help for more

. :detail For example

>>help who

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Useful command pwd/cd

l (pwd p resent w orking d ):irectory the directory of the folder in which.the user is

l cd new directory : change the working directory to the new directory.specified

The string representing the new directory is enclosed inside

the sign

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Useful command dir,mkdir/rmdirl Command dir is used to show the files under the specified

folderl .Command mkdir is used to create a new folderl Command rmdir is used to delete an empty .folder

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Useful command delete/copyfile

l .Command delete is used to delete a filel .Command copyfile is used to copy file

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Useful command who/whos

l / : .wh whos check the variables existed in the memory

Each variable is stored as a matrix in thememory

Variables mayalso be observed

.here

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Useful command what

l :what find the Matlab source code files exist in the folder.specified

Find source files in the specified directory

,By default the current folder

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Useful command which

l : .which find the full directory of the specified file

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Useful command clear/clc

l ( ).Command clear is used to clear variable from the workspace memoryl .Command clc is to clean the work space

Variable a is.gone

All the variable are

.gone

>> leara

>> learall

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Useful command help

l ,For the command help alone the Matlab will display all the.toolboxes that is available from the current system

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Useful command help

l + :help toolbox name Matlab displays all the fuction calls available.in the specified boolbox

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Useful command help

l + / :help command function name Matlab will display a brief/ .introduction of the command function designated

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Useful command helpwin

l .Command helpwin will open the online help window

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Useful command helpdesk

l , Command helpwin helpdesk and doc will open the online help.window

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Useful command doc

l .Command helpwin will open the online help window

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Useful command lookfor

l + : /lookfor keyword Matlab will display all the command function that

.is possible relevant to the keyword

Matlab shows all the/commands functions that isrelevant to the keyword

.designated

f l d

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Useful command dbtype

l + :dbtype function name Matlab will provide the source code of the

.function This command does not work for the -uilt in functions.of Matlab

f l d

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Useful command dbtype

Source code ofthe command polar

f l d

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Useful command demo

l ,Command demo will open the demonstration window from where the

.user may find help on topics in animation

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Adding path to Matlab

, Whenever Matlab receives a command it checks in the:following order whether the command isA variable -A built in functionA Matlab source code filename in the current folder

A Matlab source code filename in other folders .listed in the environment variable path

,The user may want to add directory of more folderswhere there are Matlab source code file generated

,by the user to the Matlab environment variable path such that the Matlab has access to the.source code files in those folders for later use

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Use command path to view the path of the folders

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,To add path to Matlab for source file search the:user may ( , ) Use command path path path to append

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,To add path to Matlab for source file search the:user may change from the file menuFile Set Path

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Types of commonly used data andtheir derivatives

lCommonly used type of data : , . , ( ), Real numbers pi 1 0 sqrt 2

u : + , + ,Complex numbers 4 i 5 3i / : , Character string YZU a

l .Each data is stored as a matrix in Matlab

l A /rray matrix ,is a group of the same type data the maximumdimension allowed in Matlab is 7 , a vector is a matrix with

.either one row or one columnl , There are other type of data objects such as structure and

, .cell which we will consider later this semester

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Elementary Mathematicaloperations

>>,Enter the statements next to the prompt .followed by clicking the enter button

,To turn off the display of statement result adda semicolon ; .at end of the statement

Without assigning any variablename for the result of a

,statement Matlab stores the

.result with variable ans

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Elementary Mathematicaloperationsl - :Example s of built in constantspi i o r j

l Commonly used elementary mathematic functions may be found with:command

help elfun

: , , , , , Example sin cos tan sind cosd tand and exp

1

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Try the other trigonometric functions for variable in both

.radian and degree unitQuestion : What causes the following inaccuracy and how to

correct it?

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-May put more than one statements in a line use comma or semi

.colon to separate the statements Matlab echoes the result of a,statement that ends with a comma but not for a statement that.ends with a semicolon

.Space between statements does not change the statements

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Variables

:Rules for variable naming / ,Name of a variable must begin with a character letter say

, , , , ,a b a17 E_in My_var and the maximum length of variable

name is 31 .characters For variable with name longer than,31 characters Matlab keeps the first 31 figures and ignore.the rest

:Acceptable ingredients for the variable name are/ , , .character letters numbers _

: .Variable name is case sensitive a is different from A

.No need to declare the data type of variable ,No space is allowed at middle of any variable name such

: .as is number Variables could be cleared by using command clear

.variable name

,To keep the result of a statement for later use the.user may assign a name to the result variable

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Variables, .Matlab is case sensitive therefore a is different from A

.No space is allowable in middle of a variable name

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Variables Variable cSine_1 has been removed from

memory

,Observed from response of command whos without additional

, declaration each real variable is stored as double data type and.occupies 8 bytes

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VariablesLong statement may be continued with more lines append

.at end of each line to continue the command

A space is placed between 7 and.

This technique is commonly used in script files and

.function calls programmed by the users

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Vector and matrix Vector and matrix are used to store and represent a group

of data of the same . (type A vector is a matrix of either.)one row or one column

Different assemble type

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Different assemble typeof data

Data of different type could be stored under a. (variable name structure will cover this

)later

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Construction of a vector

The elements may be separated with either a comma , or aspace .

Construction ofvector

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Construction of a vectorlConstruct a vector with command

:linspace( , , )linspace init end number of point

Operation on vector

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Operation on vectorelements

>> = [ ];s 1 3 5 2 % use [] for construction of a vector separate the% elements with either a comma , or a space>> = * +t 2 s 1

=t 3 7 11 5

l MATLAB may operate on a ingle element /of the vector matrix >> (t 3) = 2 % change the value of the 3rdelement to 2

=t 3 7 2 5

>> (t 6) = 10 % append one more element to the end of the, %vector length of the vector is increased by 2to

, %be 6 and a 0 has been padded to be the 5th.element

=t 3 7 2 5 0 10

Operation on vector

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Operation on vectorelements

>> ( ) =t 4 [] % delete the 4thelement of the vector length of%the vector has been decreased to be 5

=t 3 7 2 0 10

Use command length to(find the length total)number of element of

.vector t

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Operation on vector , , ,Find the minimum maximum sum mean of a

vector

( )may apply to matrix as well

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Operation on vector (Sort element of vector may apply to matrix

)as well

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Operation on vector

Product of vectors element by elementproduct

The dot symbol . in front of the

operators *roduct and ower -indicate the operation is element-by element

Operation on vector the

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Operation on vector thedot product

The product of a row vector and a columnvector

O ti t th t

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Operation on vector the outerproduct

The product of a column vector and a row

vector

Construction of special

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Construction of specialvectorsl Vector with elements of value 0 :or 1

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Construction of matrixl ,In matrix construction different rowsare separated with a-

semi colon

; .l Elements in a row are separated with either a space or a comma, .

Identity matrix is created ( )with command eye n wheren is the rank of the

.matrix

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Property of matrixl -Matlab stores elements in column wise style

( , ) = ( )mat2 2 4 mat2 14

Operation on matrix change value of

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Operation on matrix change value ofelements

Change value of elements in the matrix assign value

directly or by operation on elements

.Change value of an element directly

Change value of a column ofelement with operation between

columns

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Operation on matrixConstruction of a matrix from an existing matrix

Erase any number of row or column of a matrix

Erase the 5thand 6th

rows

Construct mat2 from

mat1

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Operation on matrix - flip Command flipud flips the matrix upside down

- -Command fliplf flips the matrix left hand to right

hand

Operation on matrix exchange of

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Operation on matrix exchange ofrows or columns

Exchange of the1stand the 4th

rows

Operation on matrix information of

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Operation on matrix information ofmatrix

:size find out the dimension of the matrix

: ( )ndims number of dimension rank of the matrix

(rank of mat2 is 2 2)indices

mat2 is a 4x4 matrix

Operation on matrix

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Operation on matrix transpose

:Transpose of a matrix

Add the apostrophe symbol afterthe matrix Use command transpose

Operation on matrix

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Operation on matrix transpose

Difference between and command transpose

Complex conjugate hasbeen applied upon the

elements

Complex conjugate hasbeen applied upon the

elements

Elements are kept theoriginal value

Operation on matrix

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Operation on matrix product

Product of matrices

- -Element by element product

Common matrix product

Operation on matrix

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Operation on matrix inverse

Command inv

calculates the inverse of

matrices

Operation on matrix diagonal

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Operation on matrix diagonalelements

Command diag

extracts the diagonal elements of

matrices

Operation on matrix eigenvalue

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Operation on matrix eigenvalueand characteristic polynomial

Command ( )ig A calculates the eigenvalues of matrix A ( ( ))Command round poly A returns the characteristic polynomial of

matrix A

Eigenvalues of matrix Aare the roots of the

characteristic polynomialof matrix A

Operation on matrix display of

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Operation on matrix display ofcharacteristic polynomial

Display the characteristic polynomial with

variable s

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