Matlab Introduction & Graphics Presentation

8/2/2019 Matlab Introduction & Graphics Presentation

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MATLAB Basics &MATLAB Basics &Graph icsGraph ics

Dr. R. UppaluriDr. R. UppaluriDepa r t m en t o f Chem ica lDepa r t m en t o f Ch em ica l

Eng ineer ing ,Eng ineer ing ,

I n d i an I n st i t u t e o f Tech n o lo g y ,I n d i an I n st i t u t e o f Tech n o lo g y ,

G u w a h a t iG u w a h a t i ..Emai l :Emai l : r a m g o p a l ur a m g o p a l u @@i i t gi i t g ..e rne te rne t .i n.i n


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Conten tsCon ten ts1 .1 . Qu ick Over v iewQu ick Over v iew

2 .2 . Dat a Typ es & Var iab lesDat a Typ es & Var iab les

3 .3 . Ope ra to rsOpera to rs

4 .4 . Flow Con t r o lFlow Con t r o l

5 .5 . Func t i onsFunc t i ons

6 .6 . I n p u t / Ou t pu tI n pu t / Ou t pu t

7 .7 . A r r ay Man ipu lat i onAr r ay Man ipu lat i on

8 .8 . W r i t i n g & Ru n n i n g Pr o g r a m sW r i t i n g & Ru n n in g Pr o g r a m s

9 .9 . P lo t t i ngP lo t t i ng


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1 . Qu ick Ov er v iew1 . Qu ick Ov er v iewMATLAB is termed as MATRIX LABORATORY

High Level Computer Language

Scientific Computing

Data Visualization

Interactive Programming EnvironmentQuick Testing and Debugging

Allows one to focus more on principles of programming ratherthan on programming itself

Programs can be developed in a Shorter Time than equivalentFORTRAN or C Programs

Negative: No Stand-alone applications i.e., Programs have to be

run on MATLAB environment only.


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1 . Qu ick Ov er v iew1 . Qu ick Ov er v iewAdvantages

Large number of functions involving numerical libraries

LINPACK, ODE Solver, PDE Solver, Optimization routines etc.

Many common tasks accomplished in single function call

Solution of Simultaneous Equations

Extensive Graphics Support

Plotting results with few statements

All Numerical Objects treated as Double-Precision Arrays

No need to declare data types and carry out type conversion


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1 . Qu ick Ov er v iew1 . Qu ick Ov er v iewIllustration of Advantages Gauss Elimination Code in

Fortran 90Use prec_mod conveys toload module prec_m module.

DP used for defining floatingpoint numbers

Array a(k, k+1:n) a feature notavailable in previous versions of

fortran

Code is lengthy


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1 . Qu ick Ov er v iew1 . Qu ick Ov er v iewIllustration of Advantages

Equivalent MATLAB function(No Subroutines in MATLAB)

No Definitions for floating

numbers Arrays dynamically defined

Built in MATLAB

CODE

Code is shorter and simpler than equivalent FORTRAN code
http://illust1.m/http://illust1.m/


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1 . Qu ick Ov er v iew1 . Qu ick Ov er v iewSolution of simultaneous equations

code

Unlike FORTRAN & C Compilers, MATLAB can be operatedin the interactive mode through its command window (>>)
http://illust2.m/http://illust2.m/


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1 . Qu ick Ov er v iew1 . Qu ick Ov er v iewCommand Window Each command executed upon entry

In this mode, MATLAB behaves as an electronic calculator

Symbol >> is MATLABs prompt for input

Percent Sign (%) marks the beginning of comment.

Semicolon (;)

Separates the rows of a matrix

Supresses printout of intermediate results


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1 . Qu ick Ov er v iew1 . Qu ick Ov er v iewFunctions/Programs execution at Command Window Create functions/programs with .m extension

File name identical to name of the function

For example, if Gauss Elimination routine is saved as gauss.m, then thefollowing steps can be used in the command window:

2 D T &2 D t T &


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2 . Dat a Ty p es &2 . Dat a Ty p es &

Var iab lesVar iab lesData Types Common data types (All regarded by MATLAB as arrays)

double (Numerical objects)

Char (Strings)

Logical (Logical Statements)

Numerical Objects

Class Double

Scalar is treated as 1 x 1 array

StringsSequence of characters

Logical

True

False

2 D T &2 D t T &


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Var iab lesVar iab lesFunction_handle: Important Data class Consists of the character @ followed by name of function

E.g., @sin

Function handle uses as input argument in function calls

Say we have MATLAB function plot(func, x1, x2) that plotsspecified function func from x1 and x2. Here func is a function of avariable x.

Function call to plot sinx from 0 to pi would be plot(@sin, 0, pi)

2 D t T &2 D t T &


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Var iab lesVar iab lesVariables Case sensitive

Xstart and xstart are different variables

Length of variable unlimited

First N characters are significantFor this purpose, use namelengthmax to know what is N

2 D t T &2 D t T &


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Var iab lesVar iab lesVariables Variables are local in purpose.

If Variables are shared between local function and calling program,then use global statement.

Recommended practice: Capital letters for Global variables such as

Global X Y

2 D t T &2 D t T &


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Var iab lesVar iab lesBuilt-in constants & Special Variables

2 D t T &2 Dat a T p es &


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Var iab lesVar iab lesFew examples for Special constants

2 D t T &2 Dat a Ty p es &


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Var iab lesVar iab lesArrays: Can be created in several ways

Can be entered in singleline to separate rows with

semi-colon

Can be entered in threelines as 3 x 3 matrix

2 Dat a Ty p es &2 Dat a Ty p es &


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Var iab lesVar iab lesBe careful with the semicolon ! MATLAB differentiates between row and column vectors with the

semicolon

MISPLACED SEMICOLON IMPLIES INPUT ERROR DURINGCODING.

Examples



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Var iab lesVar iab lesSingle quote Operator () For Matrix transpose

Therefore, one has to be careful with evenSingle Quote Operator while coding



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Var iab lesVar iab lesAccess to matrix elements



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Var iab lesVar iab lesCells A Cell is a sequence of arbitrary objects

Cells created by enclosing objects in { }

For displaying contents, use celldisp command



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Var iab lesVar iab lesStrings A string is a sequence of characters

Treated as Character Array in MATLABConcatenated (adding) using strcat command and extracted using colon(:) as shown in this example


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3 . Oper at o r s3 . Oper at o r sArthimetic Operators


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3 . Oper at o r s3 . Oper at o r sArthimetic Operators: Matrices


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3 . Oper at o r s3 . Oper at o r sDivision Operators

Scalars Matrices

Right division means a/b

Left division means b/a

Right division: Solution of X*A = B

Left division: Solution of A*X = B


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3 . Oper at o r s3 . Oper at o r sElemental Division


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3 . Oper at o r s3 . Oper at o r sComparison Operators


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3 . Oper at o r s3 . Oper at o r sComparison Operators: Example

Logical Operators

Used for buildingcompoundingexpressions


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3 . Oper at o r s3 . Oper at o r sLogical Operators: Example


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4 . Flow Con t r o l4 . Flow Con t r o lConditionals

Single condition Multiple Conditions

{Follows with an elsestatement in the last}


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4 . Flow Con t r o l4 . Flow Con t r o lConditionals: Example


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4 . Flow Con t r o l4 . Flow Con t r o lConditionals: Switch Statement Here Expression isevaluated, control is passedto the case that matches thevalue

Multiple Conditions


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4 . Flow Con t r o l4 . Flow Con t r o lSwitch Statement: Example

CODE
http://trig.m/http://trig.m/


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4 . Flow Con t r o l4 . Flow Con t r o lLoops: While Statement

Program for calculating number ofyears for compoundnig $ 1,000 with 6

% annual interest to $ 10,000
http://trig.m/http://trig.m/http://trig.m/http://trig.m/http://trig.m/http://trig.m/


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4 . Flow Con t r o l4 . Flow Con t r o lLoops: for Statement

Program for computing cos x from 0 to pi/2 with 5intervals
http://trig.m/http://trig.m/http://trig.m/http://trig.m/http://trig.m/


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4 . Flow Con t r o l4 . Flow Con t r o lTip: Loops be avoided when Vectors can be used

This is because Vectors execute faster in MATLAB than loops

Recall MATLAB is MATRIX Laboratory!


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4 . Flow Con t r o l4 . Flow Con t r o lBreak statement Any loop can be terminated by the break statement

Upon encountering a break statement, control is passed to the firststatement outside the look.

buildvec constructs a rowvector of arbitrary length byprompting its elements.

When an empty element isencountered, break statementallows ignoring the statement
http://trig.m/http://trig.m/http://trig.m/http://trig.m/http://trig.m/http://trig.m/http://trig.m/http://trig.m/http://trig.m/http://trig.m/http://trig.m/http://trig.m/http://trig.m/http://trig.m/http://trig.m/http://trig.m/


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4 . Flow Con t r o l4 . Flow Con t r o lContinue StatementWhen continue statement is encountered in a loop, control is passed tonext iteration without executing the statements in the current iteration.

Strips all blanks from string s1
http://trig.m/http://trig.m/http://trig.m/http://trig.m/http://trig.m/http://trig.m/http://trig.m/http://trig.m/


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4 . Flow Con t r o l4 . Flow Con t r o lReturn StatementNormally, function returns to the calling program when it runsout of the statements

Return command forces to exit.

If the error is less than 10-6,then the programme isterminated with in thestipulated number ofiterations.
http://trig.m/http://trig.m/http://trig.m/http://trig.m/http://trig.m/http://trig.m/http://trig.m/http://trig.m/http://trig.m/http://trig.m/http://trig.m/http://trig.m/http://trig.m/http://trig.m/http://trig.m/


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4 . Flow Con t r o l4 . Flow Con t r o lError StatementProgram execution can be terminated with the error function


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5 . Fu n ct ion5 . Fu n ct ionFunction Definition

Arguments separated by commas

Number of arguments may be zero

For only one output argument, enclosing brackets can beommitted.

Function should be saved with the file name function_name.m

Then only function can be accessible to other program units

File may have other functions subfunctions

Subfunctions called only by primary function function_name

or other subroutines in the fileSubfunctions not accessible to other program units
http://trig.m/http://trig.m/http://trig.m/http://trig.m/http://trig.m/http://trig.m/http://trig.m/http://trig.m/http://trig.m/http://trig.m/http://trig.m/http://trig.m/http://trig.m/http://trig.m/http://trig.m/http://trig.m/http://trig.m/http://trig.m/http://trig.m/http://trig.m/http://trig.m/


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5 . Fu n ct ion5 . Fu n ct ionCalling Functions Function can be called with fewer arguments than appearing inthe function definition

Number of input & output arguments used in the function call canbe determined by the functions nargin & nargout respectively

Above function has two inputs: x and epsilon

Also has two outputs: x and numIter
http://trig.m/http://trig.m/http://trig.m/http://trig.m/http://trig.m/http://trig.m/http://trig.m/http://trig.m/http://trig.m/http://trig.m/http://trig.m/


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5 . Fu n ct ion5 . Fu n ct ionCalling FunctionsError tolerance epsilon is an optional input that may be used tooverride the default value 10-6

code
http://trig.m/http://trig.m/http://trig.m/http://trig.m/http://trig.m/http://trig.m/http://trig.m/http://solve1.m/http://solve1.m/


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5 . Fu n ct ion5 . Fu n ct ionCalling FunctionsOutput argument numIter which contains number of iterationsmay also be omitted from the function call
http://solve1.m/http://solve1.m/http://solve1.m/http://solve1.m/http://solve1.m/http://solve1.m/


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5 . Fu n ct ion5 . Fu n ct ionEvaluating FunctionsHere we write the dx expression as a function in a different filenamed myfunc.m and link it to the source code.

In this code, if dx isdefined as yourfunc(x),

then unless the functionis renamed as y =yourfunc(x) and the file

name changed asyourfunc.m things will

not work

Solve.m

myfunc.m
http://solve1.m/http://solve1.m/http://solve1.m/http://solve1.m/http://solve1.m/http://solve1.m/http://solve1.m/http://solve1.m/http://solve1.m/http://solve1.m/http://solve1.m/http://solve1.m/http://solve1.m/http://solve1.m/http://solve2.m/http://codes/myfunc.mhttp://codes/myfunc.mhttp://solve2.m/


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5 . Fu n ct ion5 . Fu n ct ionUse of function handle

Here, call solve(@myfunc, 2) creates a function handle to myfuncand passes it to solve as an argument

Hence, the variable func in solve contains the handle to myfunc

Function passed to another function by its handle is evaluated byfeval function.

code
http://codes/myfunc.mhttp://codes/myfunc.mhttp://codes/myfunc.mhttp://codes/myfunc.mhttp://codes/myfunc.mhttp://codes/myfunc.mhttp://codes/myfunc.mhttp://codes/myfunc.mhttp://codes/myfunc.mhttp://codes/myfunc.mhttp://codes/myfunc.mhttp://solve3.m/http://solve3.m/


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5 . Fu n ct ion5 . Fu n ct ionInline functions Not complicated functions can be expressed in inline function
http://solve3.m/http://solve3.m/http://solve3.m/http://solve3.m/http://solve3.m/


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6 . I n p u t / Ou t p u t6 . I n p u t / Ou t p u tReading input
http://solve3.m/http://solve3.m/http://solve3.m/


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6 . I n p u t / Ou t p u t6 . I n p u t / Ou t p u tPrinting Output
http://solve3.m/http://solve3.m/http://solve3.m/


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6 . I n p u t / Ou t p u t6 . I n p u t / Ou t p u tPrinting Output

7 . Ar r ay7 . Ar r ay


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Man ipu la t i onMan ipu la t i onCreating Arrays

Colon operator



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Man ipu la t i onMan ipu la t i onLinspace command

Logspace command



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Man ipu la t i onMan ipu la t i onzeros

ones

rand

eye

8 . W r i t in g an d8 . W r i t in g an d
http://solve3.m/http://solve3.m/http://solve3.m/http://solve3.m/http://solve3.m/http://solve3.m/http://solve3.m/http://solve3.m/


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Ru n n in g Pr og r am sRu n n in g Pr og r am sMATLAB has two windows

Command Window

Interactive mode

Any statement that entered gets processed

Can be used for learning syntax and trying out basicideas.

Editor/Debugger

Type & Save Programs & Functions

MATLAB editor has colour coding and automaticindentation

8 . W r i t in g an d8 . W r i t in g an d
http://solve3.m/http://solve3.m/http://solve3.m/http://solve3.m/http://solve3.m/http://solve3.m/http://solve3.m/http://solve3.m/http://solve3.m/http://solve3.m/http://solve3.m/http://solve3.m/http://solve3.m/http://solve3.m/http://solve3.m/http://solve3.m/http://solve3.m/http://solve3.m/http://solve3.m/http://solve3.m/http://solve3.m/http://solve3.m/


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Ru n n in g Pr og r am sRu n n in g Pr og r am sHow to Run ProgrammesFile must be saved as M file first

A program can be run by invoking the run command fromeditors debug menu.

Variables created during MATLAB session are saved in MATLAB

workspace until they are cleared.

Variables are cleared using clear statement.
http://solve3.m/http://solve3.m/http://solve3.m/http://solve3.m/http://solve3.m/http://solve3.m/http://solve3.m/http://solve3.m/http://solve3.m/http://solve3.m/http://solve3.m/http://solve3.m/http://solve3.m/http://solve3.m/


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9 . Plo t t i n g9 . Plo t t i n gExample 1: Plot sin x and cos x on a two dimensionalplot


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9 . Plo t t i n g9 . Plo t t i n gExample 1: Plot sin x and cos x on a two dimensionalplot


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9 . Plo t t i n g9 . Plo t t i n gExample 2: Semilog plot
http://solve3.m/http://solve3.m/http://solve3.m/http://solve3.m/


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9 . Plo t t i n g9 . Plo t t i n gExample 2: Semilog plot

CODE
http://solve3.m/http://solve3.m/http://solve3.m/http://solve3.m/http://semilog%20plot%20.m/http://semilog%20plot%20.m/


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9 . Plo t t i n g9 . Plo t t i n gExample 3: Polar co-ordinatesy =

linspace(0,2*pi,100);

x = sin(2*x);

polar(x,y);

CODE
http://semilog%20plot%20.m/http://semilog%20plot%20.m/http://semilog%20plot%20.m/http://semilog%20plot%20.m/http://semilog%20plot%20.m/http://semilog%20plot%20.m/http://semilog%20plot%20.m/http://semilog%20plot%20.m/http://semilog%20plot%20.m/http://polar.m/http://polar.m/


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9 . Plo t t i n g9 . Plo t t i n gExample 4: Pie chartpie(X) draws a pie chart using the data in X. Each

element in X is represented as a slice in the pie chart.

pie(X,explode) offsets a slice from the pie. explode is avector or matrix of zeros and nonzeros that correspond to

X.

h = pie(...) returns a vector of handles to patch and text

graphics objects.
http://polar.m/http://polar.m/http://polar.m/http://polar.m/http://polar.m/http://polar.m/http://polar.m/http://polar.m/http://polar.m/http://polar.m/http://polar.m/http://polar.m/http://polar.m/http://polar.m/http://polar.m/http://polar.m/http://polar.m/


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9 . Plo t t i n g9 . Plo t t i n gExample 4: Pie chartx = [1 3 0.5 2.5 2];

explode = [0 1 0 0 0];pie(x,explode)

colormap jet

CODE
http://polar.m/http://polar.m/http://polar.m/http://polar.m/http://polar.m/http://polar.m/http://polar.m/http://polar.m/http://pie.m/http://pie.m/


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9 . Plo t t i n g9 . Plo t t i n gExample 5: Bar ChartA bar graph displays the values in a vector or matrix as

horizontal or vertical barsbar(Y) draws one bar for each element in Y. If Y is a

matrix, bar groups the bars produced by the elements ineach row.

bar(x,Y) draws a bar for each element in Y at locationsspecified in x, where x is a monotonically increasing vectordefining the x-axis intervals for the vertical bars.
http://pie.m/http://pie.m/http://pie.m/http://pie.m/http://pie.m/http://pie.m/http://pie.m/http://pie.m/http://pie.m/http://pie.m/http://pie.m/http://pie.m/http://pie.m/http://pie.m/http://pie.m/


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9 . Plo t t i n g9 . Plo t t i n gExample 5: Bar Chartx = -2.9:0.2:2.9;

bar(x,exp(-x.*x),'r')

CODE
http://pie.m/http://pie.m/http://pie.m/http://pie.m/http://pie.m/http://pie.m/http://pie.m/http://barm.m/http://barm.m/


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33--Dimensional graph plottingDimensional graph plotting3-Dimensional graphs include

Normal 3-D graphMeshes

SurfacesContour
http://barm.m/http://barm.m/http://barm.m/http://barm.m/http://barm.m/http://barm.m/http://barm.m/http://barm.m/http://barm.m/http://barm.m/http://barm.m/


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33--Dimensional graph plottingDimensional graph plotting3- D graphsplot3(x,y,t)- used to plot a 3- Dgraph of a point in space with co-

ordinates of arrays x,y,t.h = plot3(...) returns a column

vector of handles to lineseriesgraphics objects, with one handle perobject.
http://barm.m/http://barm.m/http://barm.m/http://barm.m/http://barm.m/http://barm.m/http://barm.m/http://barm.m/http://barm.m/http://barm.m/http://barm.m/http://barm.m/http://barm.m/http://barm.m/http://barm.m/http://barm.m/


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33--Dimensional graph plottingDimensional graph plottingExample 1: using plot3 commandt = -10*pi:pi/100:10*pi;

x = t.*cos(t);y = t.*sin(t);h = plot3(x,y,t);

title('Curve u(t) = ')xlabel('x')

ylabel('y')zlabel('z')grid

CODE
http://barm.m/http://barm.m/http://barm.m/http://barm.m/http://barm.m/http://barm.m/http://barm.m/http://barm.m/http://barm.m/http://barm.m/http://barm.m/http://barm.m/http://barm.m/http://barm.m/http://barm.m/http://barm.m/http://barm.m/http://barm.m/http://plota3d.m/http://plota3d.m/


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33--Dimensional graph plottingDimensional graph plottingMesh command

It is used to create a

meshmeshgrid This

function generatestwo 2-dimensional

arrays for 3-D plots.

x=[012];y=[101214];[xi,yi]=meshgrid(x,y)output

>>xi=012012012

>>yi =101010121212141414
http://plota3d.m/http://plota3d.m/http://plota3d.m/http://plota3d.m/http://plota3d.m/http://plota3d.m/http://plota3d.m/http://plota3d.m/http://plota3d.m/http://plota3d.m/http://plota3d.m/http://plota3d.m/http://plota3d.m/http://plota3d.m/http://plota3d.m/http://plota3d.m/http://plota3d.m/http://plota3d.m/http://plota3d.m/http://plota3d.m/http://plota3d.m/http://plota3d.m/http://plota3d.m/http://plota3d.m/http://plota3d.m/http://plota3d.m/http://plota3d.m/http://plota3d.m/http://plota3d.m/http://plota3d.m/http://plota3d.m/http://plota3d.m/http://plota3d.m/http://plota3d.m/http://plota3d.m/http://plota3d.m/http://plota3d.m/http://plota3d.m/http://plota3d.m/http://plota3d.m/http://plota3d.m/http://plota3d.m/http://plota3d.m/http://plota3d.m/http://plota3d.m/http://plota3d.m/http://plota3d.m/http://plota3d.m/http://plota3d.m/http://plota3d.m/http://plota3d.m/http://plota3d.m/http://plota3d.m/http://plota3d.m/http://plota3d.m/http://plota3d.m/http://plota3d.m/http://plota3d.m/http://plota3d.m/http://plota3d.m/http://plota3d.m/http://plota3d.m/http://plota3d.m/http://plota3d.m/http://plota3d.m/http://plota3d.m/http://plota3d.m/http://plota3d.m/http://plota3d.m/http://plota3d.m/http://plota3d.m/http://plota3d.m/http://plota3d.m/http://plota3d.m/http://plota3d.m/http://plota3d.m/http://plota3d.m/http://plota3d.m/


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33--Dimensional graph plottingDimensional graph plottingExample 2: using mesh commandx = -1:0.05:1;

y = x;

[xi, yi] =

meshgrid(x,y);

zi = yi.^2 - xi.^2;

mesh(xi, yi, zi)

axis off

CODE
http://plota3d.m/http://plota3d.m/http://plota3d.m/http://plota3d.m/http://plota3d.m/http://plota3d.m/http://plota3d.m/http://plota3d.m/http://plota3d.m/http://plota3d.m/http://plota3d.m/http://plota3d.m/http://plota3d.m/http://plota3d.m/http://plota3d.m/http://meshplot.m/http://meshplot.m/


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33--Dimensional graph plottingDimensional graph plotting To plot the graph of the mesh

surface together with thecontour plot beneath theplotted surface use functionm e s h c

x = -1:0.05:1;y = x;

[xi, yi] = meshgrid(x,y);

zi = yi.^2 - xi.^2;

meshc(xi, yi, zi)

axis off

Example 3: using meshc command

CODE
http://meshplot.m/http://meshplot.m/http://meshplot.m/http://meshplot.m/http://meshplot.m/http://meshplot.m/http://meshplot.m/http://meshplot.m/http://meshplot.m/http://meshplot.m/http://meshplot.m/http://meshplot.m/http://meshplot.m/http://meshplot.m/http://meshplot.m/http://meshplot.m/http://meshplot.m/http://meshplot.m/http://meshcplot.m/http://meshcplot.m/


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33--Dimensional graph plottingDimensional graph plotting surf is used to

visualize data as ashaded surface.

surfc is used to

visualize data as ashaded surface with thecontour plot beneath

the plotted surface usefunction m e s h c
http://meshcplot.m/http://meshcplot.m/http://meshcplot.m/http://meshcplot.m/http://meshcplot.m/http://meshcplot.m/http://meshcplot.m/http://meshcplot.m/http://meshcplot.m/http://meshcplot.m/http://meshcplot.m/http://meshcplot.m/http://meshcplot.m/http://meshcplot.m/http://meshcplot.m/http://meshcplot.m/http://meshcplot.m/http://meshcplot.m/http://meshcplot.m/


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33--Dimensional graph plottingDimensional graph plottingcontour is used to create

the contour surface ofthe graph

[X,Y] = meshgrid(-2:.2:2,-2:.2:3);

Z = X.*exp(-X.^2-Y.^2);

contour(X,Y,Z)

CODE

Example 4: drawing contours of a 3D graph
http://meshcplot.m/http://meshcplot.m/http://meshcplot.m/http://meshcplot.m/http://meshcplot.m/http://meshcplot.m/http://meshcplot.m/http://meshcplot.m/http://meshcplot.m/http://meshcplot.m/http://meshcplot.m/http://meshcplot.m/http://meshcplot.m/http://contourplot.m/http://contourplot.m/


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33--Dimensional graph plottingDimensional graph plottingSet t i ng t he Vi ew po i n t

MATLAB enables user to control the orientation ofthe graphics displayed in an axes. user can specify the viewpoint, view target,

orientation, and extent of the view displayed in afigure window. Theview command specifies the viewpoint by

defining azimuth and elevation with respect to theaxis origin.

3-Dimensional graph plotting
http://www-ccs.ucsd.edu/matlab/techdoc/ref/view.htmlhttp://www-ccs.ucsd.edu/matlab/techdoc/ref/view.htmlhttp://www-ccs.ucsd.edu/matlab/techdoc/ref/view.html


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33-Dimensional graph plottingDimensional graph plotting

MATLAB automatically

selects a viewpoint thatis determined bywhether the plot is 2-Dor 3-D.

For 2-D plots, thedefault is azimuth =0 and elevation =90.

For 3-D plots, thedefault is azimuth = -

37.5 and elevation =30.

3-Dimensional graph plotting


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33-Dimensional graph plottingDimensional graph plotting

[X,Y] = meshgrid([-

2:.25:2]); Z =X.*exp(-X.^2 -Y.^2);

surf(X,Y,Z)

view([180 0])

Example 5: using view command

CODE
http://viewcomm.m/http://viewcomm.m/

Documents

Matlab Introduction & Graphics Presentation