ENGR 132 exam 2

For loop

Execute a specific number of times

While loop

Executes until a specific condition is met

Example of while loop

While k<=5

k=k+1

End

For loop example

For m=[ 4 -1 0]

X=2*m

Y=m+5

End

User defined function

MATLAB program created by the user, saved as a function file, and can be used like a built in function when in the current folder

UDF syntax

function [output1,output2,...] = function_name (Input1,input2,...)

complex loop

Uses combination of for loops, while loops

MATLAB Order of Operations

Parentheses

Exponentiation

Negation

Mult/divi

Add/sub

log(x)

Natural log

exist('')

Check if variable name is a built in function

log10(x)

log base 10

cos(x)

Cosine

cosd(x)

cosine of x in degrees

Variable naming rules

1. Variables should have a descriptive name that describes their purpose without being too long

2. Variable names cannot start with numbers or have spaces or special characters except for an underscore

3. Variables are case sensitive

Array

A collection of data whose elements are arranged in rows and/or cols, can be stored and manipulated

Scalar

One-element array

Vector

One-dimensional array

Matrix

Two-dimensional array(elements are arranged in rows and cols)

Row vectors

Created with brackets and commas but commas aren't necessary

Column vectors

Created with brackets and semicolons or .' To transpose

Transpose

.' Or transpose[ ]

Regularly spaced vectors

Start:step:end

0:10:50

0 10 20 30 40 50

Linearly spaced vector

Linspace(start,end,number of elements)

Linspace(0,55,6)

0 11 22 33 44 55

Never require a period character

-addition and subtraction

-multiplication of scalar and array

-division of array by scalar

Always require a period character

-multiplication, division, and exponentiation of arrays

-division of scalar by array

-exponentiation involving a scalar

Array indexing

Array elements are referenced by their row and column location

Array indexing syntax

Array(rows,cols)

: in array indexing

Includes all elements of that dimension

Linear indexing

Array elements are referenced by a single subscript

Down each column

How linear indexing works

Concatenating array

Join arrays together

Side by side concatenation

User_data = [user1 user2 user3]

Stacked concatenation

User_data = [user1; user2; user3]

vertcat

Built in function that concatenates arrays vertically

horzcat

Butler in function that concatenates horizontally

Flowchart rectangle

process

Flowchart diamond

decision

flowchart parallelogram

input and output

Flowchart 2 rectangles

Predefined process

Plotting in matlab

Plot(x,y,linespec)

Plot professional format

Grid on

X label

Y label

Title

Legend

sgtitle('')

Subplot title

axis ([xmin xmax ymin ymax]);

Set axis limits

fprintf function

Displays output or text

\n

new line

%s

String format character

%f

Decimal point

find

Discovers linear index location of all NONzero elements

AND (&)

Which is evaluated first and(&) or or(|)

Between in matlab

x >= A & x<= B

==

Equal to