2. Python: Dictionaries Nicola Licata Charis Kao Dan Green

3. What Are Dictionaries? Similar to lists Separates the scrubs from the pros Indexed by keys that the programmer sets instead of numbers

4. Syntax #examplecode.exe loading….. #important thing to note, use {} instead of [] charizard = {‘name’: ‘Charizard’, ‘type’: ‘fire’, ‘trainer’: ‘Ash’} league = {'name': 'Zed', 'scaling': ‘AD’} print(charizard[‘type’]) print(league[‘scaling’]) >>>fire >>>AD

7. Adding Parts to a Dictionary You can easily add parts to a list by using the following code charizard = {‘name’: ‘Charizard’, ‘type’: ‘fire’, ‘trainer’: ‘Ash’} charizard[‘weakness’] = ‘water’ print(charizard) >>>{‘name’: ‘Charizard’, ‘type’: ‘fire’, ‘trainer’: ‘Ash’, ‘weakness’: water}

8. Deleting Parts of Your List Use del to delete individual parts of your list charizard = {‘name’: ‘Charizard’, ‘type’: ‘fire’, ‘trainer’: ‘Ash’} del charizard[‘trainer’] print(charizard) >>>{‘name’: ‘Charizard’, ‘type’: ‘fire’}

9. Printing The Keys You can print just the keys of the list by using the following code charizard = {‘name’: ‘Charizard’, ‘type’: ‘fire’, ‘trainer’: ‘Ash’} print(list(charizard.keys())) >>>[‘name’, ‘type’, ‘trainer’]

10. Dictionaryception You can have dictionaries within dictionaries charizard = {‘name’: ‘Charizard’, ‘type’: ‘fire’, ‘trainer’: ‘Ash’} raichu = {‘name’: ‘Raichu’, ‘type’: ‘fire’, ‘trainer’: ‘Gary’} pokemon = {‘charizard’: charizard, ‘raichu’: raichu} print(pokemon) >>> {‘charizard’: {‘name’: ‘Charizard’, ‘type’: ‘fire’, ‘trainer’: ‘Ash’}, ‘raichu’: {‘name’: ‘Raichu’, ‘type’: ‘fire’, ‘trainer’: ‘Gary’}}

11. Recap Video

12. Programming Challenge Write a code that sorts all items alphabetically in a dictionary without using any form of the sort command.

13. Just kidding, we’re reasonable.

14. Warm-Up Challenge Write a program that has multiple sub-dictionaries within one “master dictionary” print the “master dictionary” and then print each separate part of the master dictionary on its own separate line *Pro-Tip*: use other things you have learned in this class

15. Answer dict1 = {‘example’ = 1} dict2 = {‘example’ = 2} masterdict = {‘dict1’: dict1, ‘dict2’: dict2} masterlist = [dict1, dict2] print(masterdict) for x in range(len(masterlistprint)): print(masterlistprint[x])

16. Test to Separate The Men From The Boys Create a database that stores people’s names and the towns they live in Allow the user to add/remove entries Also allow the user to show specific entries