Matlab

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x=linspace(1,5,10), how many elements will the resulting vector x contain?

10

Given a vector defined as Z = linspace(3,12,4), the element in position 4 of vector z is

12

If the following matrix is in the command window M = [5 6 18; 2 4 12; 90 3 2] what number is the command M(1,3) referring to?

18

If the following loop is repeated 6 times, for a=6:X:21 disp(a) end the value of X must be

3

Given the following code segment, what is the resulting value of x. a=0; b=1; if a x=1; elseif b x=2; if a==b x=3; end if a<b x=4; end if a>b x=5; end else x=6; end

4

given the matrix G = 3 1 4 7 1 5 the output from the command G(2,1) is

4

Total number of elements in vector P P=linspace(2,10,5)

5

Given the following vectors: x=[ 2 4 0 8 10 12] y=[ 2 -4 7 10 10 -10] If z = find (x==max(x)) what is the value of z?

6

Using the following code, determine the value of the variable "Total" at the end of the code. >>q=3;Total=0;x=0:5;y=3*x-5; >>if q==1 for t=1:3 Total=Total+y(t); end elseif q==2 for s=1:3 Total=Total-y(s); end else Total=Total+y(5); end

7

Given the following Matlab code: v=4; while v<8; y=v+2; v=v+2; end; disp(y) What is the output from the disp(y) command?

8

how many elements in the vector v=[3:2:17]

8

What is not a relational operator

=

If you wanted to ask the person running your MATLAB program to provide a value for the stopping time of a calculation of projectile motion, you would use the command...

>>time_end=input('Please enter the stop time of the calculation in seconds: ');

If the variable A has been defined as a 3 by 4 matrix, the 2nd row can be removed using which of the following commands.

A(2,:)=[]

If A and B are relational operations, and the result of the command "A & B" is 1, then:

Both A and B are true

In a for-loop where "k = f:s:t", which of the following values can be correctly substituted for s (the increment value)?

Can be blank, a negative number or a positive number

Figure Window

Contains the outputs from graphics commands

Editor Window

Creates and debugs script and function files

A loop can be ended by pressing:

Ctrl+C

Function definition line _____

Defines the file as a function Defines the name of the function Defines the number and order of the input and output arguments

who

Display's a list of known variables in MATLAB'S memory

whos

Displays a list of known variables and their size and classifivation

OR |

Either one or both are true

The last command for every loop should be

End

Relational operations, i.e. x>0, will provide a "binary" 0 or 1 indicating false/true as the output, as a scalar independent of the size of the variable x (matrix/vector/scalar).

False

Command History

Logs all commands entered in the command window

~

NOT neither are true so produces a 1 if the operand is false

Assume the following commands have been entered in Matlab: >>t=0:0.1:3; >>x=t.*sin(t); >>y=cos(t)+2*sin(t); if you wanted to plot both x and y on the vertical axis of the same graph which command(s) would you enter

Plot(t,x,t,y,'r')

Workspace Window

Provides information about the variables that are stored in memory

Help Window

Provides the help information about the various functions within Matlab

clear

Removes all variables from MATLAB's memory

clear x

Removes only the indicated variable(s) from memory

Current Folder Window

Shows the files in the current/working folder

When defining a vector with the linspace function, you can set the beginning value, ending value, and ______ .

The number of intervals

which of the relational operators has the highest precedence?

They have equal precedence

The command hold on can be used to prevent the figure from being over written by another plot command

True

The script file and command window share the workspace

True

What code structure repeats commands, but requires the code to update a variable to be compared, to determine when to stop running the code?

While loop

Given the following vectors: x=[ 2 4 0 8 10 12] y=[ 2 -4 7 10 10 -10] If z = x>=x+y what is the value of z

[0 1 0 0 0 1]

Given the following vectors: x=[ 2 4 0 8 10 12] y=[ 2 -4 7 10 10 -10] If z = [ x >= y] what is the value of z?

[1 1 0 0 1 1]

Given the following vectors: x=[ 2 4 0 8 10 12] y=[ 2 -4 7 10 10 -10] If z = ~~x what is the value of z?

[1 1 0 1 1 1]

Given the following matrix K=[1,2,5,6;3,4,2,0;2,1,8,9] the output after evaluating the command K(2:3,1)' is

[3;2]

Given the following Matlab code: M=[1 5 4 1; 8 1 0 5; 3 6 7 2]; for r=1:3; for c=1:4; if M(r,c)<5; M(r,c)=8; end end end disp(M(2,:)) Indicate the output from the disp(M(2,:)) command

[8 8 8 5]

When using the plot command with no line specifiers, the resulting plot has the appearance of

a blue solid line connects the points with no markers

semicolon is typed before

a new line is entered

The output from the following Matlab commands is: a=5; b=1; c=6; if a>6 & b>c disp(a) else disp('b') end

b

format long g

best of 15 digit fixed or floating point

format short g

best of 5-digit fixed or floating point

&

both have to be true

What Matlab command will remove variables from memory?

clear

clc

clears the text from the command window

Which is a valid input command a. x = input('Enter a number: '); b. input('Enter a number: ') c. n = input('Enter your name: ','s'); d. both a and c e. a, b, and c

e. a, b, and c

Which of Matlab's windows is used to create script and function files?

editor window

format compact

eliminates empty lines to allow more lines with information displayed on the screen

A variable name may contain punctuation

false

function[outputarg]=functionname(inputarg)

file name = functionname.m

Which code structure will repeat calculations while controlling one variable automatically?

for loop

Differences between fprintf and disp

fprintf can show both variable and text from one command disp can only display a variable OR a text but not both fprintf can be used to write information to a file

What code structure will run command only if a specific condition has been met?

if statement

A function file must be saved before ______

it can be used

The output of the following MatLab commands is: k=3; c=2; m=8; if k>m | c<k disp('k') else disp(c) end

k

In the command >>fprintf('The answer is %4.1 \n',ans) the value 4 indicates...

keep at least 4 places for numbers in the statement

Variables in a function file are

local

What calculates the natural log of x

log(x)

Command Window

main window where you can enter variables and run programs

First executable line in a function file

must be the function definition, otherwise it is considered a script file

function[A]=RectArea(a,b)

one output two input arguments also can be written as function A (without brackets)

Order of operations

parentheses exponential multiplication and division addition and subtraction

order of precedence

parentheses exponentiation logical NOT multiplication, division addition, subtraction relational operators logical AND logical OR

The variables in a script file are

recognized in the Command Window

sum(A)

returns the added values of the elements in vector A

mean(A)

returns the average value of vector A

inv(A)

returns the inverse of the matrix A

max(A)

returns the max value of the vector A

dot(A,B)`

returns the scalar product of vectors A and B

format short e

scientific notation with 4 decimal places

In the command >>fprintf('The answer is %4.1 \n',ans) the value 1 indicates...

show 1 decimal place

In order to use the units of degrees in MATLAB's trig functions, you can use which of the following commands. tan(x*180/pi) tand(x)

tand(x)

A user defined function can be used in ________ (like a built in function)

the command window, a script file, or in another function

The functions xlsread() and xlswrite() can be used to read and write Excel files provided

the full file structure ('C:/folder/filename.xlsx') is given the file ('filename.xlsx') is in the active MATLAB folder

The functions xlsread() and xlswrite() can be used to read and write Excel files provided

the full file structure ('C:/folder/filename.xlsx') is given the file ('filename.xlsx') is in the active MATLAB folder

function trajectory(v,h,g)

the inputs and no outputs

V=linspace(1,12,7) the number 7 indicates -

the number of elements

When a function file is saved, the name of the file should be ________

the same as the name of the function

A variable name must begin w a letter

true

No spaces are allowed between characters in variable names

true

function[mpay,tpay]=loan(amount,rate,year)

two output arguments and three input arguments

function[V,S]=spherevolarea(r)

two output one input variables

When the total number of iterations required is not known, the best type of loop to use is

while-loop

if a=0:1:5 and b=1:1:6 then, x=[a,b] is

x = 1 3 5 7 9 11

x=eye(3)

x= 1 0 0 0 1 0 0 0 1

linspace(x,y,z)

x=first element y=last element z=number of elements

v=[x,y,z]

x=first element y=spacing z=last element