Matlab Environment
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Chapter 2
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Matlab for Engineers
In this chapter we’ll…
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• Get started with Matlab
• Explore the Matlab windows
• Solve some problems using
Matlab
• Learn how to save our work
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Matlab for Engineers
Section 2.1
Getting Started
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• In Windows or Apple operating
systems click on the desktop icon
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matlab
At the shell prompt
Matlab for Engineers
Matlab opens to a default
window configuration
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Matlab for Engineers
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• Matlab uses a standard
windows menu bar
• To exit Matlab use the
close icon
Matlab for Engineers
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Command Window
Current Directory
Enter commands at the prompt
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MATLAB Windows
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Command History
Workspace Window
Matlab for Engineers
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You can use
the command
window much
like you’d use
a calculator
The standard
order of
operation rules
apply
Let’s try Practice Exercise 2.1
Matlab for Engineers
To watch this demonstration, click in the figure window. To move to
the next slide use the down arrow
Section 2.2
Matlab Windows
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• Matlab uses several different
windows to display data,
commands and results.
• They are not necessarily all open
at once
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Matlab for Engineers
Let’s look at the windows
one at a time
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Matlab for Engineers
Command Window
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• Similar to a scratch pad
• Once you hit enter, you can’t edit
Command Window
any commands
• You can retype them or use the
arrow keys to retrieve commands
and edit them before hitting enter
again
Matlab for Engineers
Command History
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• Records the commands you issue
in the command window
• When you exit the command
window, or when
you
issue
the
clc
Command History
command, the command window
is cleared
• But the command history remains
Matlab for Engineers
Command History
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• You can transfer commands from
the command history to the
command window
– Double click on a command
– Click and drag
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Matlab for Engineers
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Matlab for Engineers
To watch this demonstration, click in the figure window. To move to
the next slide use the down arrow
Workspace Window
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• Keeps track of the variables you’ve
defined
– Name
– Value
Workspace Window
– Class
– Size
– Bytes
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• You may need to click on the name bar
and select size and bytes in order to
see these parameters
Matlab for Engineers
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Matlab for Engineers
To watch this demonstration, click in the figure window. To move to
the next slide use the down arrow
Rate of Change
Rate of temperature change, degrees/hour
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When you define variables
in the command window,
they are listed in the
workspace window
Matlab for Engineers
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Vector
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2-D
Matrix
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Matlab for Engineers
Current Directory
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• The current directory window is a
list of files
• When you try to load information
from a file or try to save
information – Matlab uses the
current directory
Matlab for Engineers
Document Window
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• If you double click on any variable
in the workspace window Matlab
launches a document window
containing the array editor
• You can edit variables in the array
editor
Matlab for Engineers
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Document Window
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Matlab for Engineers
Figure Window
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• When Figures are created a new
window opens
• It’s extremely easy to create
graphs in Matlab
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Matlab for Engineers
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The semicolon suppresses
the output from each
command
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Matlab for Engineers
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Matlab for Engineers
Editing Window
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• This window allows you to type
and save a series of commands
without executing them
• There are several ways to open
an editing window
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– From the file menu
– With the new file icon
Matlab for Engineers
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Open an editing window
from the file menu or with
the new file icon
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Matlab for Engineers
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Save and Run
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Write your code in the editing window,
then run it using the Save and Run icon
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Matlab for Engineers
Section 2.3
Solving Problems with Matlab
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• We’ve already solved some
simple problems
• We need to understand how
Matlab works to solve more
complicated problems
Matlab for Engineers
Variables
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• MATLAB allows you to assign a
value to a variable
• A=3
• Should be read as A is assigned a
value of 3
• Use the variables in subsequent
calculations
Matlab for Engineers
Naming Variables
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• All names must start with a letter
• They may contain letters,
numbers and the underscore ( _ )
• Names are case sensitive
• There are certain keywords you
can’t use
Matlab for Engineers
Use the iskeyword function
for a list of keywords
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iskeyword
ans =
'break'
'case'
'catch'
'continue'
'else'
'elseif'
'end'
'for'
'function'
'global'
'if'
'otherwise'
'persistent'
'return'
'switch'
'try'
'while'
Matlab for Engineers
You can reassign function
names
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• Matlab will let you use built-in
function names as variables – but
it’s a really bad idea
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• sin = 3
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changes sin from a
function to a variable
name
Matlab for Engineers
Practice Exercise 2.2
Which of these names are allowed
in Matlab?
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•
•
•
•
•
•
•
•
•
•
•
•
test
Test
if
x
x
my-book
my_book
x
Thisisoneverylongnamebutisitstillallowed?
1stgroup
x
group_one
zzaAbc
z34wAwy?12#
x x
sin
bad
log
idea
Matlab for Engineers
Matrices in Matlab
The basic data type
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• Group of numbers arranged into
rows and columns
• Single Value (Scalar)
– Matrix with one row and one column
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• Vector (One dimensional matrix)
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– One row or one column
• Matrix (Two dimensional)
Matlab for Engineers
Scalar Calculations
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• You can use MATLAB like you’d
use a calculator
Command
Prompt
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>> 9 + 10
ans=19
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Result
Matlab for Engineers
Assignment Operator
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• To define a variable a we might
type
a=1+2
which should be read as:
a is assigned a value of 1+2
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Matlab for Engineers
How is the assignment operator
different from an equality?
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• In algebra the equation
x=3+5
means that both sides are the same
• In computers when we say
x=3+5
we are telling the machine to store the
value on the right hand side of the
equation in a memory location, and to
name that location x
Matlab for Engineers
Is that really different?
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• Yes!!!
• In algebra this is not a true statement
x=x+1
• In computers (assignment statements)
it means replace the value in the
memory location named x, with a new
value equal to x+1
Matlab for Engineers
Order of Operation
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• Same as you’ve learned in math
class
• Same as your calculator
– Parentheses first
– Exponentiation
– Multiplication / division
– Addition / subtraction
Matlab for Engineers
Order of Operation
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5*(3+6)
= 45
5*3+6
= 21
100
White space does not matter!!!
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5*3 + 6
= 21
Matlab for Engineers
Parentheses
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• Use only ( )
• { } and [ ] mean something
different
• MATLAB does not assume
operators
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5 * (3+4) not 5(3+4)
Matlab for Engineers
Compute from left to right
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5*6/6*5 = 25
5*6/(6*5)
= 1
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Matlab for Engineers
Here’s an example
Find the surface area of a cylinder
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2.5
3
3.5
4
4.5
5
time, hour
r = radius
r=5
h = height
h = 10
π r2
2π r * h
100
π r2
200
300
400
500
100
200
300
400
500
SA  2r  2rh  2r (r  h)
2
Matlab for Engineers
Rate of Change
Rate of temperature change, degrees/hour
-5
-4.5
-4
-3.5
-3
-2.5
-2
-1.5
-1
-0.5
0
0
0.5
1
1.5
2
2.5
3
3.5
4
4.5
5
time, hour
100
200
300
400
500
100
200
300
400
500
Matlab for Engineers
To watch this demonstration, click in the figure window. To move to
the next slide use the down arrow
Array Operations
Rate of Change
Rate of temperature change, degrees/hour
-5
-4.5
-4
-3.5
-3
-2.5
-2
-1.5
-1
-0.5
0
0
0.5
1
1.5
2
2.5
3
3.5
4
4.5
5
time, hour
• Using Matlab as a glorified
calculator is OK, but its real
strength is in matrix manipulations
100
200
300
400
500
100
200
300
400
500
Matlab for Engineers
Rate of Change
Rate of temperature change, degrees/hour
-5
-4.5
-4
-3.5
-3
-2.5
-2
-1.5
-1
-0.5
0
0
0.5
1
1.5
2
2.5
3
3.5
4
4.5
5
time, hour
To create a row vector, enclose a list of values
in brackets
100
200
300
400
500
100
200
300
400
500
Matlab for Engineers
Rate of Change
Rate of temperature change, degrees/hour
-5
-4.5
-4
-3.5
-3
-2.5
-2
-1.5
-1
-0.5
0
0
0.5
1
1.5
2
2.5
3
3.5
4
4.5
5
time, hour
100
You may use either a space or a
comma as a “delimiter” in a row
vector
200
300
400
500
100
200
300
400
500
Matlab for Engineers
Rate of Change
Rate of temperature change, degrees/hour
-5
-4.5
-4
-3.5
-3
-2.5
-2
-1.5
-1
-0.5
0
0
0.5
1
1.5
2
2.5
3
3.5
4
4.5
5
time, hour
100
Use a semicolon as a delimiter to create a
new row
200
300
400
500
100
200
300
400
500
Matlab for Engineers
Rate of Change
Rate of temperature change, degrees/hour
-5
-4.5
-4
-3.5
-3
-2.5
-2
-1.5
-1
-0.5
0
0
0.5
1
1.5
2
2.5
3
3.5
4
4.5
5
time, hour
100
Use a semicolon as a delimiter to create a
new row
200
300
400
500
100
200
300
400
500
Matlab for Engineers
Rate of Change
Rate of temperature change, degrees/hour
-5
-4.5
-4
-3.5
-3
-2.5
-2
-1.5
-1
-0.5
0
0
0.5
1
1.5
2
2.5
3
3.5
4
4.5
5
time, hour
100
200
300
400
500
100
200
300
400
500
Hint: It’s easier to keep track of how many
values you’ve entered into a matrix, if you
enter each row on a separate line. The
semicolons are optional
Matlab for Engineers
Shortcuts
Rate of Change
Rate of temperature change, degrees/hour
-5
-4.5
-4
-3.5
-3
-2.5
-2
-1.5
-1
-0.5
0
0
0.5
1
1.5
2
2.5
3
3.5
4
4.5
5
time, hour
100
200
300
400
500
100
200
300
400
500
• While a complicated matrix might have
to be entered by hand, evenly spaced
matrices can be entered much more
readily. The command
b= 1:5
or the command
b = [1:5]
both return a row matrix
Matlab for Engineers
Rate of Change
Rate of temperature change, degrees/hour
-5
-4.5
-4
-3.5
-3
-2.5
-2
-1.5
-1
-0.5
0
0
0.5
1
1.5
2
2.5
3
3.5
4
4.5
5
time, hour
100
200
300
400
500
100
200
300
400
500
The default increment is 1, but if you
want to use a different increment put
it between the first and final values
Matlab for Engineers
To calculate spacing
between elements use…
Rate of Change
Rate of temperature change, degrees/hour
-5
-4.5
-4
-3.5
-3
-2.5
-2
-1.5
-1
-0.5
0
0
0.5
1
1.5
2
2.5
3
3.5
4
4.5
5
time, hour
• linspace
• logspace
100
200
300
400
500
100
200
300
400
500
Matlab for Engineers
Rate of Change
Rate of temperature change, degrees/hour
-5
-4.5
-4
-3.5
-3
-2.5
-2
-1.5
number of elements in
the array
-1
-0.5
0
0
0.5
1
1.5
2
2.5
3
3.5
4
4.5
5
time, hour
Initial value in the
array
Final value in the
array
100
200
300
400
500
100
200
300
400
500
Matlab for Engineers
Rate of Change
Rate of temperature change, degrees/hour
-5
-4.5
-4
-3.5
-3
-2.5
-2
-1.5
-1
-0.5
0
0
0.5
1
1.5
2
2.5
3
3.5
4
4.5
5
time, hour
number of elements in
the array
Initial value in the
array expressed
as a power of 10
100
200
300
Final value in the
array expressed
as a power of 10
400
500
100
200
300
400
500
Matlab for Engineers
Hint
Rate of Change
Rate of temperature change, degrees/hour
-5
-4.5
-4
-3.5
-3
-2.5
-2
-1.5
-1
-0.5
0
0
0.5
1
1.5
2
2.5
3
3.5
4
4.5
5
time, hour
100
• You can include mathematical
operations inside a matrix
definition statement.
• For example
200
300
400
500
100
200
300
400
500
a = [0: pi/10: pi]
Matlab for Engineers
Mixed calculations between
scalars and arrays
Rate of Change
Rate of temperature change, degrees/hour
-5
-4.5
-4
-3.5
-3
-2.5
-2
-1.5
-1
-0.5
0
0
0.5
1
1.5
2
2.5
3
3.5
4
4.5
5
time, hour
100
200
300
400
500
100
200
300
400
500
• Matrices can be used in many
calculations with scalars
• There is no confusion when we
perform addition and subtraction
• Multiplication and division are a little
different
• In matrix mathematics the
multiplication operator (*) has a very
specific meaning
Matlab for Engineers
Rate of Change
Rate of temperature change, degrees/hour
-5
-4.5
-4
-3.5
-3
-2.5
-2
-1.5
-1
-0.5
0
0
0.5
1
1.5
2
2.5
3
3.5
4
4.5
5
time, hour
100
200
300
400
500
100
200
300
400
500
Matlab for Engineers
Rate of Change
Rate of temperature change, degrees/hour
-5
-4.5
-4
-3.5
-3
-2.5
-2
-1.5
-1
-0.5
0
0
0.5
1
1.5
2
2.5
3
3.5
4
4.5
5
time, hour
Addition between arrays is
performed on
corresponding elements
100
200
300
400
500
100
200
300
400
500
Matlab for Engineers
Rate of Change
Rate of temperature change, degrees/hour
-5
-4.5
-4
-3.5
-3
-2.5
-2
-1.5
-1
-0.5
0
0
0.5
1
1.5
2
2.5
3
3.5
4
4.5
5
time, hour
Multiplication between
arrays is performed on
corresponding elements if
the .* operator is used
100
200
300
400
500
100
200
300
400
500
Matlab for Engineers
Rate of Change
Rate of temperature change, degrees/hour
-5
-4.5
-4
-3.5
-3
-2.5
-2
-1.5
-1
-0.5
0
0
0.5
1
1.5
2
2.5
3
3.5
4
4.5
5
time, hour
100
200
300
400
500
100
200
300
400
500
Matlab interprets * to mean matrix
multiplication. The arrays a and b are
not the correct size for matrix
multiplication in this example
Matlab for Engineers
Array Operations
Rate of Change
Rate of temperature change, degrees/hour
-5
-4.5
-4
-3.5
-3
-2.5
-2
-1.5
-1
-0.5
0
0
0.5
1
1.5
2
2.5
3
3.5
4
4.5
5
time, hour
• Array multiplication
• Array division
• Array exponentiation
100
200
300
In each case the size of the arrays must match
400
500
100
200
300
400
500
Matlab for Engineers
.*
./
.^
The matrix capability of Matlab makes
it easy to do repetitive calculations
Rate of Change
Rate of temperature change, degrees/hour
-5
-4.5
-4
-3.5
-3
-2.5
-2
-1.5
-1
-0.5
0
0
0.5
1
1.5
2
2.5
3
3.5
4
4.5
5
time, hour
• For example, assume you have a
list of angles in degrees that you
would like to convert to radians.
– First put the values into a matrix.
– Perform the calculation
100
200
300
400
500
100
200
300
400
500
Matlab for Engineers
Rate of Change
Rate of temperature change, degrees/hour
-5
-4.5
-4
-3.5
-3
-2.5
-2
-1.5
-1
-0.5
0
0
0.5
1
1.5
2
2.5
3
3.5
4
4.5
5
time, hour
100
200
300
400
500
100
200
300
400
500
Matlab for Engineers
Rate of Change
Rate of temperature change, degrees/hour
-5
-4.5
-4
-3.5
-3
-2.5
-2
-1.5
-1
-0.5
0
0
0.5
1
1.5
2
2.5
3
3.5
4
4.5
5
time, hour
100
200
300
400
500
100
200
300
400
500
Either the * or the .* operator can be
used for this problem, because it is
composed of scalars and a single
matrix
The value of pi is built into Matlab as a
floating point number, called pi
Matlab for Engineers
More about pi
Rate of Change
Rate of temperature change, degrees/hour
-5
-4.5
-4
-3.5
-3
-2.5
-2
-1.5
-1
-0.5
0
0
0.5
1
1.5
2
2.5
3
3.5
4
4.5
5
time, hour
100
200
300
400
500
100
200
300
400
500
• Because pi is an irrational
number, it can not be expressed
exactly with a floating point
representation
• The Matlab constant , pi, is really
an approximation.
• If you find sin(pi) Matlab returns a
very small number.
Matlab for Engineers
Transpose
Rate of Change
Rate of temperature change, degrees/hour
-5
-4.5
-4
-3.5
-3
-2.5
-2
-1.5
-1
-0.5
0
0
0.5
1
1.5
2
2.5
3
3.5
4
4.5
5
time, hour
• The transpose operator changes
rows to columns or vice versa.
100
200
300
400
500
100
200
300
400
500
Matlab for Engineers
Rate of Change
Rate of temperature change, degrees/hour
-5
-4.5
-4
-3.5
-3
-2.5
-2
-1.5
-1
-0.5
0
0
0.5
1
1.5
2
2.5
3
3.5
4
4.5
5
time, hour
100
200
300
400
500
100
200
300
400
500
The transpose operator
makes it easy to create
tables
Matlab for Engineers
Rate of Change
Rate of temperature change, degrees/hour
-5
-4.5
-4
-3.5
-3
-2.5
-2
-1.5
-1
-0.5
0
0
0.5
1
1.5
2
2.5
3
3.5
4
4.5
5
time, hour
100
200
300
400
500
100
200
300
400
500
table =[degrees;radians]’ would have given
the same result
Matlab for Engineers
Rate of Change
Rate of temperature change, degrees/hour
-5
-4.5
-4
-3.5
-3
-2.5
-2
-1.5
-1
-0.5
0
0
0.5
1
1.5
2
2.5
3
3.5
4
4.5
5
time, hour
100
200
300
400
500
100
200
300
400
500
The transpose
operator works on
both one dimensional
and two dimensional
arrays
Matlab for Engineers
Number Display
Rate of Change
Rate of temperature change, degrees/hour
-5
-4.5
-4
-3.5
-3
-2.5
-2
-1.5
-1
-0.5
0
0
0.5
1
1.5
2
2.5
3
3.5
4
4.5
5
time, hour
100
200
300
400
500
100
200
300
400
500
• Scientific Notation
– Although you can enter any number in
decimal notation, it isn’t always the best
way to represent very large or very small
numbers
– In Matlab, values in scientific notation are
designated with an e between the decimal
number and exponent. (Your calculator
probably uses similar notation.)
Matlab for Engineers
Rate of Change
Rate of temperature change, degrees/hour
-5
-4.5
-4
-3.5
-3
-2.5
-2
-1.5
-1
-0.5
0
0
0.5
1
1.5
2
2.5
3
3.5
4
4.5
5
time, hour
100
200
300
400
500
100
200
300
400
500
It is important to omit blanks between
the decimal number and the exponent.
For example, Matlab will interpret
6.022 e23
as two values (6.022 and 1023 )
Matlab for Engineers
Display Format
Rate of Change
Rate of temperature change, degrees/hour
-5
-4.5
-4
-3.5
-3
-2.5
-2
-1.5
-1
-0.5
0
0
0.5
1
1.5
2
2.5
3
3.5
4
4.5
5
time, hour
100
200
300
400
500
100
200
300
400
500
• Multiple display formats are available
• No matter what display format you
choose, Matlab uses double precision
floating point numbers in its
calculations
• Matlab handles both integers and
decimal numbers as floating point
numbers
Matlab for Engineers
Default
Rate of Change
Rate of temperature change, degrees/hour
-5
-4.5
-4
-3.5
-3
-2.5
-2
-1.5
-1
-0.5
0
0
0.5
1
1.5
2
2.5
3
3.5
4
4.5
5
time, hour
100
200
300
400
500
100
200
300
400
500
• The default format is called short
• If an integer is entered it is
displayed without trailing zeros
• If a floating point number is
entered four decimal digits are
displayed
Matlab for Engineers
Other formats
Rate of Change
Rate of temperature change, degrees/hour
-5
-4.5
-4
-3.5
-3
-2.5
-2
-1.5
-1
-0.5
0
0
0.5
1
1.5
2
2.5
3
3.5
4
4.5
5
time, hour
100
200
300
400
500
100
200
300
400
500
• Changing the format affects all
subsequent displays
– format long results in 14 decimal
digits
– format bank results in 2 decimal
digits
– format short returns the display to
the default 4 decimal digits
Matlab for Engineers
Really Big and Really Small
Rate of Change
Rate of temperature change, degrees/hour
-5
-4.5
-4
-3.5
-3
-2.5
-2
-1.5
-1
-0.5
0
0
0.5
1
1.5
2
2.5
3
3.5
4
4.5
5
time, hour
100
200
300
400
500
100
200
300
400
500
• When numbers become too large or
too small for Matlab to display using
the default format, it automatically
expresses them in scientific notation
• You can force scientific notation with
– format short e
– format long e
Matlab for Engineers
Common Scale Factor
Rate of Change
Rate of temperature change, degrees/hour
-5
-4.5
-4
-3.5
-3
-2.5
-2
-1.5
-1
-0.5
0
0
0.5
1
1.5
2
2.5
3
3.5
4
4.5
5
time, hour
100
200
300
400
500
100
200
300
400
500
• For long and short formats, a
common scale factor is applied to
the entire matrix if some of the
elements become very large, or
very small. This scale factor is
printed along with the scaled
values.
Matlab for Engineers
Rate of Change
Rate of temperature change, degrees/hour
-5
-4.5
-4
-3.5
-3
-2.5
-2
-1.5
-1
-0.5
0
0
0.5
1
1.5
2
2.5
3
3.5
4
4.5
5
time, hour
100
Common Scale
Factor
200
300
400
500
100
200
300
400
500
Matlab for Engineers
Two other formats
Rate of Change
Rate of temperature change, degrees/hour
-5
-4.5
-4
-3.5
-3
-2.5
-2
-1.5
-1
-0.5
0
0
0.5
1
1.5
2
2.5
3
3.5
4
4.5
5
time, hour
• format +
• format rat
100
200
300
400
500
100
200
300
400
500
Matlab for Engineers
Spacing in the command
window
Rate of Change
Rate of temperature change, degrees/hour
-5
-4.5
-4
-3.5
-3
-2.5
-2
-1.5
-1
-0.5
0
0
0.5
1
1.5
2
2.5
3
3.5
4
4.5
5
time, hour
• The format command also allows
us to control how tightly
information is spaced in the
command window
– format compact
– format loose – (default)
100
200
300
400
500
100
200
300
400
500
Notice that the value of A is still
being displayed using the rat
format, because we haven’t
changed it back to format short
• Most of the examples in this
presentation use format compact
Matlab for Engineers
Section 2.4
Saving Your Work
Rate of Change
Rate of temperature change, degrees/hour
-5
-4.5
-4
-3.5
-3
-2.5
-2
-1.5
-1
-0.5
0
0
0.5
1
1.5
2
2.5
3
3.5
4
4.5
5
time, hour
• If you save a MATLAB session, all
that is saved are the values of the
variables you have named
100
200
300
400
500
100
200
300
400
500
Matlab for Engineers
Rate of Change
Rate of temperature change, degrees/hour
-5
-4.5
-4
-3.5
-3
-2.5
-2
-1.5
-1
-0.5
0
0
0.5
1
1.5
2
2.5
3
3.5
4
4.5
5
time, hour
Variables are saved,
not the work space
100
200
300
400
500
100
200
300
400
500
Matlab for Engineers
Rate of Change
Rate of temperature change, degrees/hour
-5
-4.5
-4
-3.5
-3
-2.5
-2
-1.5
-1
-0.5
0
0
0.5
1
1.5
2
2.5
3
3.5
4
4.5
5
time, hour
Save either by using the file menu or...
100
Save with a command in the
command window
200
300
400
500
100
200
300
400
500
Matlab for Engineers
Matlab automatically saves
to a .mat file
Rate of Change
Rate of temperature change, degrees/hour
-5
-4.5
-4
-3.5
-3
-2.5
-2
-1.5
-1
-0.5
0
0
0.5
1
1.5
2
2.5
3
3.5
4
4.5
5
time, hour
• If you want to save to another
format, such as .dat, you need to
explicitly tell the program
100
200
save <file_name> <variable_list> -ascii
300
400
500
100
200
300
400
500
Matlab for Engineers
Script M-files
Rate of Change
Rate of temperature change, degrees/hour
-5
-4.5
-4
-3.5
-3
-2.5
-2
-1.5
-1
-0.5
0
0
0.5
1
1.5
2
2.5
3
3.5
4
4.5
5
time, hour
100
200
300
400
• If you want to save your work, you
need to create an M-file
• File->New->M-file
• Type your commands in the edit
window that opens
500
100
200
300
400
500
Matlab for Engineers
Rate of Change
Rate of temperature change, degrees/hour
-5
-4.5
-4
-3.5
-3
-2.5
-2
-1.5
-1
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• The file is saved into the current
directory
• It runs in the command window
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Matlab for Engineers
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Rate of temperature change, degrees/hour
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Comments
Rate of Change
Rate of temperature change, degrees/hour
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• Be sure to comment your code
– Add your name
– Date
– Section #
– Assignment #
– Descriptions of what you are doing
and why
Matlab for Engineers
Rate of Change
Rate of temperature change, degrees/hour
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time, hour
The % sign identifies comments
You need one on each line
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Matlab for Engineers
Summary
Rate of Change
Rate of temperature change, degrees/hour
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time, hour
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Introduced the MATLAB Windows
Basic matrix definition
Save and retrieve MATLAB data
Create and use script M-files
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Matlab for Engineers