emptyList = [] lst = ['one', 'two', 'three', 'four'] # list of strings lst2 = [1, 2, 3, 4] #list of integers lst3 = [[1, 2], [3, 4]] # list of lists lst4 = [1, 'ramu', 24, 1.24] # list of different datatypes print(lst4)

lst = ['one', 'two', 'three', 'four'] #find length of a list print(len(lst))

lst = ['one', 'two', 'three', 'four'] lst.append('five') # append will add the item at the end print(lst)

#syntax: lst.insert(x, y) lst = ['one', 'two', 'four'] lst.insert(2, "three") # will add element y at location x print(lst)

#syntax: lst.remove(x) lst = ['one', 'two', 'three', 'four', 'two'] lst.remove('two') #it will remove first occurence of 'two' in a given list print(lst)

lst = ['one', 'two', 'three', 'four'] lst2 = ['five', 'six'] #append lst.append(lst2) print(lst)

lst = ['one', 'two', 'three', 'four'] lst2 = ['five', 'six'] #extend will join the list with list1 lst.extend(lst2) print(lst)

#del to remove item based on index position lst = ['one', 'two', 'three', 'four', 'five'] del lst[1] print(lst) #or we can use pop() method a = lst.pop(1) print(a) print(lst)

lst = ['one', 'two', 'three', 'four'] #remove an item from list lst.remove('three') print(lst)

#keyword 'in' is used to test if an item is in a list lst = ['one', 'two', 'three', 'four'] if 'two' in lst: print('AI') #keyword 'not' can combined with 'in' if 'six' not in lst: print('ML')

#reverse is reverses the entire list lst = ['one', 'two', 'three', 'four'] lst.reverse() print(lst)

#create a list with numbers numbers = [3, 1, 6, 2, 8] sorted_lst = sorted(numbers) print("Sorted list :", sorted_lst) #original list remain unchanged print("Original list: ", numbers)

#print a list in reverse sorted order print("Reverse sorted list :", sorted(numbers, reverse=True)) #orginal list remain unchanged print("Original list :", numbers)

lst = [1, 20, 5, 5, 4.2] #sort the list and stored in itself lst.sort() # add element 'a' to the list to show an error print("Sorted list: ", lst)

lst = [1, 20, 'b', 5, 'a'] print(lst.sort()) # sort list with element of different datatypes.

lst = [1, 2, 3, 4, 5] abc = lst abc.append(6) #print original list print("Original list: ", lst)

#let's take a string s = "one,two,three,four,five" slst = s.split(',') print(slst)

s = "This is applied AI Course" split_lst = s.split() # default split is white-character: space or tab print(split_lst)

lst = [1, 2, 3, 4] print(lst[1]) #print second element #print last element using negative index print(lst[-2])

numbers = [10, 20, 30, 40, 50,60,70,80] #print all numbers print(numbers[:]) #print from index 0 to index 3 print(numbers[0:4])

print (numbers) #print alternate elements in a list print(numbers[::2]) #print elemnts start from 0 through rest of the list print(numbers[2::2])

lst1 = [1, 2, 3, 4] lst2 = ['varma', 'naveen', 'murali', 'brahma'] new_lst = lst1 + lst2 print(new_lst)

numbers = [1, 2, 3, 1, 3, 4, 2, 5] #frequency of 1 in a list print(numbers.count(1)) #frequency of 3 in a list print(numbers.count(3))

#loop through a list lst = ['one', 'two', 'three', 'four'] for ele in lst: print(ele)

# without list comprehension squares = [] for i in range(10): squares.append(i**2) #list append print(squares)

#using list comprehension squares = [i**2 for i in range(10)] print(squares)

#example lst = [-10, -20, 10, 20, 50] #create a new list with values doubled new_lst = [i*2 for i in lst] print(new_lst) #filter the list to exclude negative numbers new_lst = [i for i in lst if i >= 0] print(new_lst) #create a list of tuples like (number, square_of_number) new_lst = [(i, i**2) for i in range(10)] print(new_lst)

#let's suppose we have a matrix matrix = [ [1, 2, 3, 4], [5, 6, 7, 8], [9, 10, 11, 12] ] #transpose of a matrix without list comprehension transposed = [] for i in range(4): lst = [] for row in matrix: lst.append(row[i]) transposed.append(lst) print(transposed)

#with list comprehension transposed = [[row[i] for row in matrix] for i in range(4)] print(transposed)