Movatterモバイル変換

ListIntroductionUsed for storing different types of data unlike arraysExample-1 student = [10, "Amar", 'M', 50, 55, 57, 67, 47]Example-2 e_list = [] #Empty ListIndexing + Slicing can be applied on listExample-1 print(student[1]) Gives "Amar"Example-2 print(student[0: 3: 1])Prints [10, "Amar", 'M']Example-3 student[::] Print all elements

ListExamplesExample-1 #Create list with integer numbersnum = [10, 20, 30, 40, 50]print(num)print("num[0]: %dtnum[2]: %dn" % (num[0], num[2]))Example-2 #Create list with stringsnames = ["Ram", "Amar", "Thomas"]print(names)print("names[0]: %stnames[2]: %sn" % (names[0], names[2]))Example-3 #Create list with different dtypesx = [10, 20, 1.5, 6.7, "Ram", 'M']print(x)print("x[0]: %dtx[2]: %ftx[4]: %stx[5]: %cn" %(x[0], x[2], x[4], x[5]))

ListCreating list using range()Example #Create listnum = list(range(4, 9, 2))print(num)

ListUpdating list1 Creation lst = list(range(1, 5))print(lst)[1, 2, 3, 4]2 append lst.append(9)print(lst)[1, 2, 3, 4, 9]3 Update-1 lst[1] = 8print(lst)[1, 8, 3, 4, 9]4 Update-2 lst[1: 3] = 10, 11print(lst)[1, 10, 11, 4, 9]5 delete del lst[1]print(lst)[1, 11, 4, 9]6 remove lst.remove(11)print(lst)[1, 4, 9]7 reverse lst.reverse()print(lst)[9, 4, 1]

ListConcatenation of Two List'+' operator is used to join two listExample x = [10, 20, 30]y = [5, 6, 7]print(x + y)

ListRepetition of List'*' is used to repeat the list 'n' timesExample x = [10, 20, 30]print(x * 2)

ListMembership of List'in' and 'not in' operators are used to check, whether an element belongs to the listor notExample x = [1, 2, 3, 4, 5]a = 3print(a in x)Returns True, if the item is foundin the listExample x = [1, 2, 3, 4, 5]a = 7print(a not in x)Returns True, if the item is notfound in the list

ListAliasing And Cloning ListsAliasing: Giving new name for the existing listExample x = [10, 20, 30, 40]y = xNote: No separate memory will be allocated for yCloning / Copy: Making a copyExample x = [10, 20, 30, 40]y = x[:] <=> y = x.copy()x[1] = 99print(x)print(y)Note: Changes made in one list will not reflect other

ListExercise1. To find the maximum & minimum item in a list of items2. Implement Bubble sort3. To know how many times an element occurred in the list4. To create employee list and search for the particular employee

ListTo find the common items#To find the common item in two listsl1 = ["Thomas", "Richard", "Purdie", "Chris"]l2 = ["Ram", "Amar", "Anthony", "Richard"]#Covert them into setss1 = set(l1)s2 = set(l2)#Filter intersection of two setss3 = s1.intersection(s2)#Convert back into the listcommon = list(s3)print(common)

ListNested List#To create a list with another list as elementlist = [10, 20, 30, [80, 90]]print(list)

ListList ComprehensionsExample-1: Create a list with squares of integers from 1 to 10#Version-1squares = []for x in range(1, 11):squares.append(x ** 2)print(squares)#Version-2squares = []squares = [x ** 2 for x in range(1, 11)]print(squares)List comprehensions represent creation of new lists from an iterable object(list, set,tuple, dictionary or range) that satisfies a given condition

ListList ComprehensionsExample-2: Get squares of integers from 1 to 10 and take only the even numbers from theresulteven_squares = [x ** 2 for x in range(1, 11) if x % 2 == 0]print(even_squares)List comprehensions represent creation of new lists from an iterable object(list, set,tuple, dictionary or range) that satisfies a given condition

ListList ComprehensionsExample-3: #Adding the elements of two list one by one#Example-1x = [10, 20, 30]y = [1, 2, 3, 4]lst = []#Version-1for i in x:for j in y:lst.append(i + j)#Version-2lst = [i + j for i in x for j in y]#Example-2lst = [i + j for i in "ABC" for j in "DE"]print(lst)List comprehensions represent creation of new lists from an iterable object(list, set,tuple, dictionary or range) that satisfies a given condition

TupleIntroductionA tuple is similar to list but it is immutable

TupleCreating TuplesTo create empty tupletup1 = ()Tuple with one itemtup1 = (10, )Tuple with different dtypestup3 = (10, 20, 1.1, 2.3, "Ram", 'M')Tuple with no bracest4 = 10, 20, 30, 40Create tuple from the listlist = [10, 1.2, "Ram", 'M']t5 = tuple(list)Create tuple from ranget6 = tuple(range(4, 10, 2))

TupleAccessing TuplesAccessing items in the tuple can be done by indexing or slicing method, similar tothat of list

TupleBasic Operations On Tupless = (10, "Ram", 10, 20, 30, 40, 50)To find the length of the tupleprint(len(s))Repetition operatorfee = (25.000, ) * 4print(fee)Concatenate the tuples using *ns = s + feeprint(ns)Membershipname = "Ram"print(name in s)Repetitiont1 = (1, 2, 3)t2 = t1 * 3print(t2)

TupleFunctions To Process Tupleslen() len(tpl) Returns the number of elements in the tuplemin() min(tpl) Returns the smallest element in the tuplemax() max() Returns the biggest element in the tuplecount() tpl.count(x) Returns how many times the element ‘x’ is found in the tupleindex() tpl.index(x) Returns the first occurrence of the element ‘x’ in tpl.Raises ValueError if ‘x’ is not found in the tuplesorted() sorted(tpl) Sorts the elements of the tuple into ascending order.sorted(tpl, reverse=True) will sort in reverse order

TupleExercise1. To accept elements in the form of a a tuple and display thier sum and average2. To find the first occurrence of an element in a tuple3. To sort a tuple with nested tuples4. To insert a new item into a tuple at a specified location5. To modify or replace an existing item of a tuple with new item6. To delete an element from a particular position in the tuple

Movatterモバイル変換

Change Language

Python programming : List and tuples

Embed presentation

Recommended

More Related Content

What's hot

Similar to Python programming : List and tuples

More from Emertxe Information Technologies Pvt Ltd

Recently uploaded

In this document

Python programming : List and tuples