fprintf command And fprintf format in MATLAB

•  The fprintf command in MATLAB Programming use to displays formatted text which is centered on the icon and this fprint function can display formatSpec with a contents of var.

• formatSpec  in MATLAB can be a character vector with the single quotes, or a string scalar.

Formatting for the fprint function in MATLAB : -

•  formatting is starts with the a percentage sign, % and it will end with the conversion character.

• Remember conversion character is required in formatting Operator.

• But you can use the  flags, field , identifier,width, and subtype,precision operators between % and conversion character.
  

 List for the Conversion Character

Conversion Character in MATLAB

Example of fprint function in MATLAB

The command

fprintf('YES YES');

displays this text 'YES YES' on the icon.

The follow command

fprintf('YES YES = %d',16);

uses the decimal notation format (%d) to display the variable 16.

Using fprintf in MATLAB With Function

Let's see this example for define a function in MATLAB : -

function []= fun2let(n)
 if n > 90.00
 fprintf('>>letter grade to %d is:A+\n',n)
 elseif n<=89.49 && n>=80.00
 fprintf('>>letter grade to %d is:B+\n',n)
 % YOU COMPLETE YOUR FUNCTION WITH OTHER TESTS
 elseif n<59.5 
 %    grade='Fail'
    fprintf('>> letter grade to %d is:Fail\n',n)
 end
 end

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frozenset() function in python With Example Code - Python Function

•  The frozenset() function in python is an inbuilt function is Python.

• That Function takes an iterable object as input and makes them immutable. 

• it freezes the iterable objects and makes them unchangeable.
• frozen sets can be helpful in  Dictionary it can be used as key because it remain the same after creation.
  

Parameter for the  frozenset() function in Python

it use a single parameter iterable which can be ( dictionary, tuple, etc.)

Return value : - 

• The frozenset() function in python returns an immutable frozenset.

• it return the empty frozenset only if no parameters are passed to this function.

Example code for frozenset function in python :- 

# tuple of vowels
vowels = ('a', 'e', 'i', 'o', 'u')

fset = frozenset(vowels)
print('The frozen set is:', fset)
print('The empty frozen set is:', frozenset())

# frozensets are immutable
fSet.add('v')

OUTPUT

Example code for frozenset

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fft matlab Function And ftt code with Example

 Fast Fourier transform of fft function in matlab.

Syntax:-

Y = fft(X)
Y = fft(X,n)
Y = fft(X,n,dim)

Discprition for fft matlab Function

If x is an vector then it will return the Fourier transform of that vector

Let x is an matrix then fft(X) assume the colum as a vactory and return Fourier transform of each column.

Now let assume X is an multidimensional array then fft(X) treats the values of first array dimension only if the size of that array is not equal to 1 as vector and gives the Fourier transform of each vector

Cases with the fft() MATLAB Function

Y = fft(X,n) returns the n-point DFT.

Case 1

X is an vector and the length of X is lower then n. X will be padded with trailing zeros to length n

Case 2

X is an vector and the length of X is Higher then n. X will be truncated to length n

Case 2

X is an matrix then each column of that matrix treated as in the vector case

Case 2

multidimensional array X is treated as like fft(X) the "first array dimension only if the size of that array is not equal to 1" treated as in the vector case

Y = fft(X,n,dim) gives the Fourier transform along with the dimension dim.

Example Code For ftt() function in MATLAB

Use the help of Fourier transforms to find the frequency components of a signal buried in noise.

Fs = 1000;            % Sampling frequency                    
T = 1/Fs;             % Sampling period       
L = 1500;             % Length of signal
t = (0:L-1)*T;        % Time vector

Form a signal containing a 50 Hz sinusoid of amplitude 0.7 and a 120 Hz sinusoid of amplitude 1.

S = 0.7*sin(2*pi*50*t) + sin(2*pi*120*t);

Corrupt the signal with zero-mean white noise with a variance of 4.

X = S + 2*randn(size(t));

Plot the noisy signal in the time domain. It is difficult to identify the frequency components by looking at the signal X(t).

plot(1000*t(1:50),X(1:50))
title('Signal Corrupted with Zero-Mean Random Noise')
xlabel('t (milliseconds)')
ylabel('X(t)')


Compute the Fourier transform of the signal.

Y = fft(X);

Compute the two-sided spectrum P2. Then compute the single-sided spectrum P1 based on P2 and the even-valued signal length L.

P2 = abs(Y/L);
P1 = P2(1:L/2+1);
P1(2:end-1) = 2*P1(2:end-1);

Define the frequency domain f and plot the single-sided amplitude spectrum P1. The amplitudes are not exactly at 0.7 and 1, as expected, because of the added noise. On average, longer signals produce better frequency approximations.

f = Fs*(0:(L/2))/L;
plot(f,P1) 
title('Single-Sided Amplitude Spectrum of X(t)')
xlabel('f (Hz)')
ylabel('|P1(f)|')

Now, take the Fourier transform of the original, uncorrupted signal and retrieve the exact amplitudes, 0.7 and 1.0.

Y = fft(S);
P2 = abs(Y/L);
P1 = P2(1:L/2+1);
P1(2:end-1) = 2*P1(2:end-1);

plot(f,P1) 
title('Single-Sided Amplitude Spectrum of S(t)')
xlabel('f (Hz)')
ylabel('|P1(f)|')

OUTPUT For Example of fft () matlab:-

fft () matlab output

---

fftshift matlab

---

fourier transform matlab

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Learn about the Matlab linspace function With Example

 Matlab linspace is used to Generate linearly spaced vector.

Syntax for Matlabn Linspace: -

y = linspace(x1,x2)
y = linspace(x1,x2,n)

• y = linspace(x1,x2) give a row vector which is made with the 100 points with equal distance between x1 and x2

• y = linspace(x1,x2,n) return the n number of points and these point keep the distance of (x2-x1)/(n-1).

• This Matlab linspace function is very similar to the colon operator, “:” But linspace function in matlab direct control over the number of points and always include the endpoints.

Example of Matlab linspace

Create a vector of 100 evenly spaced points in the interval [-5,10]. 
y = linspace(-5,10);

Create a vector of 7 evenly spaced points in the interval [-5,7]. 
y1 = linspace(-5,7,7)

output

  Example of Matlab linspace

Important points : -

• x1 and x2 gives the interval for points which is generated by Matlab linspace.
• Data Types: single | double | datetime | duration
  
  • Complex Number Support: Yes 

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Example program for super function in python

 super() function in python return the proxy object it's also a temporary object of the superclass and this object help us to access the method of base class.

Super function has two use :-

• This function Working with Multiple Inheritance
• Help us to avoid base class name explicitly
  

Example of super function in python:-

if it use single inheritance then this function help us to refer base class by super()

class Mammal(object):
  def __init__(self, mammalName):
    print(mammalName, 'is a warm-blooded animal.')
    
class Dog(Mammal):
  def __init__(self):
    print('Dog has four legs.')
    super().__init__('Dog')
    
d1 = Dog()

OUTPUT

Dog has four legs.
Dog is a warm-blooded animal.

We can also change the name of base class Let see

# changing base class to CanidaeFamily
class Dog(CanidaeFamily):
  def __init__(self):
    print('Dog has four legs.')

    # no need to change this
    super().__init__('Dog')

Well super function in python is an call method for base class via delegation and that is called indirection and this happen at run then time in between this time we can also use the other base classes at different times.

Example program for super() with Multiple Inheritance

class Animal:
  def __init__(self, Animal):
    print(Animal, 'is an animal.');

class Mammal(Animal):
  def __init__(self, mammalName):
    print(mammalName, 'is a warm-blooded animal.')
    super().__init__(mammalName)
    
class NonWingedMammal(Mammal):
  def __init__(self, NonWingedMammal):
    print(NonWingedMammal, "can't fly.")
    super().__init__(NonWingedMammal)

class NonMarineMammal(Mammal):
  def __init__(self, NonMarineMammal):
    print(NonMarineMammal, "can't swim.")
    super().__init__(NonMarineMammal)

class Dog(NonMarineMammal, NonWingedMammal):
  def __init__(self):
    print('Dog has 4 legs.');
    super().__init__('Dog')
    
d = Dog()
print('')
bat = NonMarineMammal('Bat')

OUTPUT

Example program for super function in python

 

 

Method Resolution Order (MRO)For super() function in python

MRO is use to maintain the order at the persence of the multiple inheritance and ir can also view by using the __mro__ attribute.

>>> Dog.__mro__
(<class 'Dog'>, 
<class 'NonMarineMammal'>, 
<class 'NonWingedMammal'>, 
<class 'Mammal'>, 
<class 'Animal'>, 
<class 'object'>)

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setattr() function in Python use to set the value of an attribute.

setattr() function in Python

 

Syntax : -

setattr(object, name, value)

If you want to read the object then use the getattr() function.

• Parameters For setattr():- 

It takes three parameters and these are:-

• Object : - the object whose value is going to be set in python program.

• Name - set the name of attribute.

• value - Desire value given to the attribute

setattr() function in python doesn't return the value.

Example program for setattr() function in Python

class Person:
    name = 'Adam'
    
p = Person()
print('Before modification:', p.name)

# setting name to 'John'
setattr(p, 'name', 'John')

print('After modification:', p.name)

Output:-

program for setattr() function in Python

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Example for getattr() function in python

 getattr() function in python is sued to get the value of an object attribute and it return the default value if no attribute of that object is found.

Example for getattr() function in python

 

The reason of using getattr() function because it return the default value.Now let see the basic syntax : -

getattr(object_name, attribute_name[, default_value])

Example of getattr() function in python

this program will help you to teach about how to use the getattr() function in python

class Student:
    student_id=""
    student_name=""

    # initial constructor to set the values
    def __init__(self):
        self.student_id = "101"
        self.student_name = "Adam Lam"

student = Student()
# get attribute values by using getattr() function
print('\ngetattr : name of the student is =', getattr(student, "student_name"))

# but you could access this like this
print('traditional: name of the student is =', student.student_name)

Why use getattr() function

• This function helps to get the object attribute value with the help of Name of that attr. or you can also manually set the input attribute name by console.

• This function also give the freedom for set the default value according to your need.

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