python exercises – Page 3 – Pythonista Planet

In Python, a list is a data structure that stores a list of items in an arranged order. We can create a list by using square brackets with items inside and use commas to separate each item. In this post, I have compiled some examples of using lists in Python. I hope these examples would help you understand the working of lists in Python. Let's dive right in. 1. Python list of strings groceryList = ["Rice","Wheat","Barley"] print(groceryList) 2. Python list of numbers myNumbers = [1,5,9,16,28] print(myNumbers) 3. Python list with duplicate values myNumbers = [1,5,5,9,9,9,16,28] print(myNumbers) 4. Python list that contains different data type values heterogeneousList = ["Python",123,24.5,True,35,"a"] print(heterogeneousList) 5. Finding the length of a list in Python ProgrammingList = ["CSharp","Python","PHP","R"] print(len(ProgrammingList)) 6. Finding the index of items in a Python list fruits = ["apple","banana","mango"] bananaIndex = fruits.index("banana") mangoIndex = fruits.index("mango") print(bananaIndex) print(mangoIndex) pythonList = ["p","y","t","h","o","n"] # to get the 1st item print(pythonList[0]) #to get the 4th item print(pythonList[3]) # Negative indexing to get last item print(pythonList[-1]) # To get second last item print(pythonList[-2]) 7. Slicing of lists in Python myList = ['p','y','t','h','o','n','i','s','t','a'] # elements from 5 to 8 print(myList[4:8]) # from 1st element to 4th element print(myList[:4]) # from 8th element to last element print(myList[7:]) # from 1st to last elements print(myList[:]) # negative slicing print(myList[-1:-9]) print(myList[-5:]) print(myList[:-4]) 8. Adding items to a list using insert() and append() in Python If we use the append method to add an item to a list, the new item will be added at the end of the list. numbers = [10,20,30,40,50,60] numbers.append(70) print(numbers) If we use the insert method to add items to a list, we have to specify the position at which we want to insert an item. The insert() method takes two arguments [ insert(position,item) ]. numbers = [10,20,30,40,50,60] numbers.insert(0,5) print(numbers) 9. Merging two lists using extend method in Python list1 = ["Apple","Orange","Mango"] list2 = ["Grape","Strawberry"] list1.extend(list2) print(list1) 10. Removing items from a list using pop() in Python x = [23,45,67,89,34,12] # removing the last element x.pop() print(x) # removing the 0th index element x.pop(0) print(x) 11. Removing items from a list using remove() in Python dryFruits = ["Cashew nuts","Dates","Almonds","Raisins"] dryFruits.remove("Raisins") print(dryFruits) 12. Remove all the elements from a list in Python dryFruits = ["Cashew nuts","Dates","Almonds","Raisins"] dryFruits.clear() print(dryFruits) 13. Creating a copy of a list in Python dryFruits = ["Cashew nuts","Dates","Almonds","Raisins"] d = dryFruits.copy() print(d) 14. Finding the number of times an item is present in a list myList = [1,2,2,3,3,3,4,4,4,4] count = myList.count(4) print(count) 15. Reversing a list in Python myList = ["Pen","Pencil","Book"] myList.reverse() print(myList) 16. Sorting a list in Python myList = ["Pen","Pencil","Book","Eraser"] myList.sort() print(myList) 17. Deleting items in a list using del keyword colorList = ["Red","Blue","Green","Yellow","Orange","Purple"] # deleting an item del colorList[2] print(colorList) # deleting multiple items del colorList[1:3] print(colorList) # deleting the entire list del colorList 18. Nested list in Python nestedList = ["Apple",["Ball",1,2.5],['a',128]] print(nestedList) print(nestedList[0]) print(nestedList[1]) print(nestedList[2]) 19. Creating a list using the list() constructor myList = list(("Mac","Windows","Linux")) print(myList) 20. Checking whether an item exists in a list or not myList = list(("Mac","Windows","Linux")) if "Mac" in myList: print("Yes") else: print("No") if "Linux" not in myList: print("Yes") else: print("No") 21. Concatenating lists in Python myList1 = ["Mac","Windows","Linux"] myList2 = ["Book","Pencil","Pen"] combinedList = myList1 + myList2 print(combinedList) 22. Repeating a list in Python myList1 = ["Mac","Windows"] combinedList = myList1 * 3 print(combinedList) 23. Python list of numbers of the power of 2 myList = [2**x for x in range(10)] print(myList)