Question

EENG 1910: Project I – Introduction to Electrical Engineering Assignment-8

1. Create a MATLAB function that will take as inputs the radius

(r) and height (h) of a cone and calculate its volume. The formula to compute the volume of a cone is as follows.

1

? = 3 ??2ℎ

Write a descriptive comment on the use of the function so that

the user by typing help nameofyourfunction has all the necessary information to use your function.

In each of the following questions (2. & 3.), first, evaluate the given MATLAB code for each of the test cases without using MATLAB. Then, using MATLAB, check the answers you obtained first.

2.

if n >	1	a. n	=	-25	m	=	?
m =	n+1	b. n	=	2	m	=	?
elseif	n==0	c. n	=	10	m	=	?
m =	n	d. n	=	0	m	=	?
else
m =	n-10

end

3.

switch letter                a. letter = ‘p’ case ‘x’       b. letter = ‘y’ disp(‘Hello’)         c. letter = ‘q’ case{‘y’, ‘Y’}          d. letter = ‘Q’

disp(‘Yes’)           e. letter = ‘x’ case ‘Q’

disp(‘Quit’)

otherwise

disp(‘Error’)

end

Note: When you copy and paste codes into MATLAB, some characters may not correctly translate. As a result, you may have to correct them for the script to run properly.

4. A switch statement can often be used in place of a nested if- else or an if statement with many elseif clauses. Switch statements are used when an expression is tested to see whether it is equal to one of several possible values.

The script pickPizzaCase.m posted on Canvas is written using a case statement. Analyze it and convert it to if-elseif-else statement.

5. Write MATLAB script that will prompt the user for a temperature in degrees Celsius, and then a letter ‘F’ for Fahrenheit or ‘K’ for Kelvin. The script should work weather a capital or small case letter is entered. The script will then print the corresponding temperature in the scale specified by the user. For example, the outputs might look as follows.

>> conversioncode

Please enter a temperature value in Celsius: 45 Do you want K or F? k

The temperature in Kelvin is: 318.15.

Please enter a temperature value in Celsius: 29.3 Do you want K or F? f

The temperature in Fahrenheit is: 84.74.

>> conversioncode

Please enter a temperature value in Celsius: 78 Do you want K or F? K

The temperature in Kelvin is: 351.15.

>> conversioncode

Please enter a temperature value in Celsius: 74 Do you want K or F? P

Please enter F or K!

Note: Lesson-8 has a sample code that could simply be modified. Also, conversioncode is simply the name that I have given to my script. The conversions can be performed using the formulas below.

? = ? + 273.15

? = 9 ? + 32

5

6. Use a for loop to sum the elements in the following vector: V=[10, 27, -66, 43, 72, 87, 56,98, 33, 23.5, 8.5, 77.7, 36, 24,11, 85, 55, 63, 4, 39, 100, -96, 4, 41, 189, -9,78.3, -83]. You will need to first determine the size (length) of the vector. Check your answer using the MATLAB sum function.

7. Repeat the previous problem, this time using a while loop.

8. Create a function called “isInt” to check whether an input number is an integer. The function should display a sentence of the form: “22.5 is not an integer!” or “99 is an integer!” if the inputs were respectively 22.5 and 99.

9. In chemistry, the pH of an aqueous solution is a measure of its acidity. The pH scale ranges from 0 to 14, inclusive. A solution with a pH of 7 is said to be neutral, a solution with a pH greater than 7 is basic, and a solution with a pH less than 7 is acidic. Write a script that will prompt the user for the pH of a solution, and will print whether it is neutral, basic, or acidic. If the user enters an invalid pH, an error message should be printed.

Answer 1

Question 1

function [V] = Volume_Cone(r,h)
% This function Volume_Cone(r,h) calculates the volume of a cone
% 'h' is the height of the cone
% 'r' is the radius of the cone
% 'V is the volume of the cone

V = 3*pi*r*h;
end

Question 2

The given segment is

if n>1
m = n+1
elseif n == 0
m = n
else
m = n - 10
end

First Case : n = -25

Since n is not greater than 1 and n is not equal to 0, the command m = n - 10 will be executed and the value of m will be m = -25 - 10 = -35

Checking using MATLAB

clc;

n = -25;
if n>1
m = n+1
elseif n == 0
m = n
else
m = n - 10
end

After execution command window is

m =

-35

>>

Second Case : n = 2

Since n >1 , the command , m = n+1 will be executed and the value of m will be m = n+1 = 3

Checking using MATLAB

clc;

n = 2;
if n>1
m = n+1
elseif n == 0
m = n
else
m = n - 10
end

After execution command window is

m =

3

>>

Third Case : n = 10

Since n >1 , the command , m = n+1 will be executed and the value of m will be m = 10+1 = 11

Checking using MATLAB

clc;

n = 10;
if n>1
m = n+1
elseif n == 0
m = n
else
m = n - 10
end

After execution command window is

m =

1

>>

Fourth Case : n = 0

Since n is not greater than 1, the next else will be checked, ie if n == 0. Since n = 0, the command , m = n will be executed and the value of m will be m = n= 0

Checking using MATLAB

clc;

n = 0;
if n>1
m = n+1
elseif n == 0
m = n
else
m = n - 10
end

After execution command window is

m =

0

>>

Question 3

clc;
letter = 'p';

switch letter
case 'x'
disp('Hello');
case {'y','Y'}
disp('Yes');
case 'Q'
disp('Quit');
otherwise
disp('Error')
end

First : letter = 'p'

Since the letter is not in any of the cases of switch, the command window will have Error displayed

Checking using MATLAB

clc;
letter = 'p';

switch letter
case 'x'
disp('Hello');
case {'y','Y'}
disp('Yes');
case 'Q'
disp('Quit');
otherwise
disp('Error')
end

After execution command window is

Error
>>

Second : letter = 'y'

Since the letter is in one of the case statement, the command window will have Yes displayed

Checking using MATLAB

clc;
letter = 'y';

switch letter
case 'x'
disp('Hello');
case {'y','Y'}
disp('Yes');
case 'Q'
disp('Quit');
otherwise
disp('Error')
end

After execution command window is

Yes
>>

Third : letter = 'q'

Since the letter is not in any of the cases of switch, the command window will have Error displayed

Checking using MATLAB

clc;
letter = 'q';

switch letter
case 'x'
disp('Hello');
case {'y','Y'}
disp('Yes');
case 'Q'
disp('Quit');
otherwise
disp('Error')
end

After execution command window is

Error
>>

Fourth: letter = 'Q'

Since the letter is in one of the case statement, the command window will have Quit displayed

Checking using MATLAB

clc;
letter = 'Q';

switch letter
case 'x'
disp('Hello');
case {'y','Y'}
disp('Yes');
case 'Q'
disp('Quit');
otherwise
disp('Error')
end

After execution command window is

Quit
>>

Fifth: letter = 'x'

Since the letter is in one of the case statement, the command window will have Hello displayed

Checking using MATLAB

clc;
letter = 'x';

switch letter
case 'x'
disp('Hello');
case {'y','Y'}
disp('Yes');
case 'Q'
disp('Quit');
otherwise
disp('Error')
end

After execution command window is

Hello
>>

Question 4

function [Temp] = ConversionCode()
%This function converts the temperature in degree Celcius to degree
%Farenheit of Kelvin according to the user's choice

C = input('Please enter a temperature value in Celsius:');

choice = input(' Do you want K or F?');

switch choice
case {'k','K'}
K = C + 273.15;
disp('The temperature in Kelvin is:');
disp(K);   
  
case {'f','F'}
F = 9*C + 32;
disp('The temperature in Fahrenheit is:');
disp(F);
otherwise
disp('Please enter F or K!');
end
  

end

Question 5

clc;

V=[10, 27, -66, 43, 72, 87, 56,98, 33, 23.5, 8.5, 77.7, 36, 24,11, 85, 55, 63, 4, 39, 100, -96, 4, 41, 189, -9,78.3, -83];
N = length(V);

S = 0;
for i=1:N
S = S + V(i);
end

disp('The Sum f the numbers is:')
disp(S);

disp('The Sum of the numbers using the function sum is:')
sum(V)

Question 6

clc;

V=[10, 27, -66, 43, 72, 87, 56,98, 33, 23.5, 8.5, 77.7, 36, 24,11, 85, 55, 63, 4, 39, 100, -96, 4, 41, 189, -9,78.3, -83];
N = length(V);

S = 0;
i = 1
while i<= N
S = S + V(i);
i = i + 1;
end

disp('The Sum f the numbers is:')
disp(S);

disp('The Sum of the numbers using the function sum is:')
sum(V)

Question 7

function [] = isInt(n)
%This function checks whether the number is an integer or not

if floor(n)==n
fprintf('"%d is an integer"\n', n);
else
fprintf('"%d is not an integer"\n',n);
end

Question 08

clc

pH = input('Enter the pH of the solution');

if pH <7 & pH >=0
disp('The solution is acidic');
elseif pH==7
disp('The solution is neutral');
elseif pH>7 & pH<=14
disp('The solution is basic');
else
disp('Error!!!. pH will be between 0 and 14');
end