THE MATLAB ENVIRONMENTVARIABLESBASIC COMMANDSHELP

HP 100 – MATLABWednesday, 8/27/2014

www.clarkson.edu/class/honorsmatlab

Who are we?

Jim: Junior Aeronautical – Mechanical Engineer elmerjc@clarkson.edu

Joe: Senior Mechanical Engineer quinzijn@clarkson.edu

Quote of the Week

“This is a full time campus. Believe me, there’s nothing exciting going on downtown.”

Prof. Cetinkaya

Before We Begin:

Any Questions? Comments? Concerns? Feel free to contact Jim or Joe

We can set up small group tutoring or one-on-one

You can email us with questions or concerns We are here for you! Even if it isn't about

MATLAB

Homework

Create and submit a PDF file using the publish tool in Matlab

Feel free to work in groups! Do NOT have identical code Questionable integrity will be examined This is your FIRST & FINAL WARNING

The MATLAB Interface

Open MATLAB:

Start All Programs MATLAB

MATLAB Interface [cont.]

Double Click on variable and it will open this “excel” like editor

The Editor

The Editor is a supped up ‘notepad’ It is where you will be spending most of your time. It allows you to write your code, save it, open it up again,

run it as well as many more advance options. Open it from:

New Script The “New” icon has options to create other different

things like functions and GUIs

The Editor [cont.]

Line Number

Save & Run script

Where MATLAB will try to point out possible errors with your code, and offer suggestions! How nice!

MATLAB FUNDAMENTALS

• The 'Supped-Up Graphing Calculator'– In the command window:

25 + 5 <<enter>>

• Result:ans = 30 <<line spaces removed>>

– So… what does this mean?• You can use the command window like a

scratch-pad or calculator, using familiar math symbols.Addition: a + b Multiplication: a * b

Subtraction: a - b Division: a / b

Exponentiation: a^b

MATLAB FUNDAMENTALS

Order of Operations Parentheses left to right Exponents left to right Division AND Multiplication left to right Addition AND Subtraction left to right

MATLAB FUNDAMENTALS

Creating Variables / Arrays The assignment operator =

<<variable_name>> = <<data to be stored>>; Variable names must begin with a letter

and can only contain letters, numbers, and the underscore.

Examples: x = 1; y = [1 2 3 4]; z = [1 0 0; 0 1 0; 0 0 1];

MATLAB FUNDAMENTALS

Variables and Arrays Variables store values (numbers and text) Scalar

Vector

Array (Matrix)

MATLAB FUNDAMENTALS

Mathematical Operations with arrays Use .* ./ .^ when using operation on an array or

vector Array Indexing

Indexing an array is to specify a specific location to extract its value and or to perform an operation.

Arrays are indexed as follows: A(i,j) Refers to the ith row

and jth column.

9 8 7

6 5 4

3 2 1

i

j

Elementary MATLAB CommandsFunction Syntax (What to type in) Example

Display disp(‘Hello’)

disp(x)

Hello

5

Trig Functions sin(pi/2) 1

Square Root sqrt(16) 4

Remainder rem(15,6) 3

Size d=[1 2 3;4 5 6]

size(d)

[2 3]

Clear clear (Clears all variables)

Clear Screen clc (Clears Screen)

Numerical Display

See page 39 in your texts

MATLAB Command Display Example

format short 4 decimal points 3.1416

format long 14 decimal points 3.14159265358979

format short e 4 decimal points 3.1416e+000

format long e 14 decimal digits 3.141591643589793e+000

format bank 2 decimal digits 3.14

format + +, -, blank +

format rat Fractional form 355/113

Help command

Help function: Universal! Solves many problems created by Jim and

Joe!! ‘help’ is a great place to start when

totally lost ‘help _______’ insert a function in the blank

ie cos, solve, plot, etc… Mathworks website has an explanation

for every function in matlab

Publishing

Go to the Publish tab Click the drop box below the Publish icon

and select edit publishing options Change the output format to PDF

Click the Publish icon

Questions?

Questions? HW # 1

Due by 5:00 PM, Wednesday September 3rd, to cuhonorsmatlab@gmail.com

You are to submit: PDF file of your published code Make sure to use comments % Question 2.2 Problems: 2.2, 2.3, 2.4

Homework Example

Go to Problem 2.3 in your books Step 1: Create variables for numbers 1-9 Step 2: Evaluate each equation using

only the variables you created Step 3: Create a 3x3 array containing

numbers 1-9 Step 4: Evaluate each equation using

only references to the array you created