Dictionary and Set in Python | Shraddha Khapra #Lec 04

 # =============== Dictionary and set (built-in data  type) =====================
# Dictionaries are used to store to store in key:value paris
# They are unorderd,mutable(changable) & don't allow duplicate keys

dictionary = {
    "name" : "asad shams ud din",
    "age" : 20,
    "class" : "bscs",
    "language" : "english,urdu",
    "skill":["python","C++","Javascript"],    #we can store list in dictionary
    "expierence" : ("sotware engineer","data  science","machine learning"), #store tuple in dictionary
    2004:2025  #we can store like this
}

print(dictionary,type(dictionary))

print(dictionary["age"])

print(dictionary["name"])  #access values in dictionary

dictionary["age"] = 21

print(dictionary)     #change values in dictionary

dictionary["location"] = "bahawalpur,punjab,pakistan"   #adding new value in dictionary

print(dictionary)

dictionary["language"] = "saraiki"    #overwrite

null_dict =  {}       #create null dictionary

print(null_dict)

# Nested dictionary   (dictionary in dictionary)

student = {

    "st_name" :  "asad",

    "p_detail" :  {

        "cell" : 923055570630,

        "mail" : "asadshamsofficial@gmail.com",

        "locatiom" : "bahawalpur,punjab,pakistan"

    }

}

print(student["p_detail"]["cell"])  #access value in nested dictionary

# ========================= Dictionary Methoed ================================

data = {

    "name" : "asad",

    "age" : 40

}

#legenth of dictionary

print("legenth of dictionary key : ",len(data.keys()))

# data.keys()   #return all keys

print(data.keys())

print(list(data.keys()))    #type cast in  list convert in list data type we change values across  datatype store disctionary in list or list dictionary

#return all values   data.values()

print(data.values())

#return all key values as  a tuple  data.item()

pairs = list(data.items())

print(pairs[0])  #we can covert it into list and also apply list  methoeds

#returns the key  according the value   data.get()

# we have two methoeds to do this opreation

# 1. simple methoed

"""print(data["name2"])"""  #if error occur it will  give you  error

#2. Dictionary methoed

"""print(data.get("name2"))"""  #when error occur in this methoed it will return none

# we use the get methoed the major reason is if we got error then our next code will not execute(run) so thats a problem that's why we use get methoed or many other prefrence to get rid from this methoed

# insert the specified item to the dictionary   :  data.update({new item in dictionary})

#we can  update old value with this methoed

"""

print(data.update({"name":"asad shams ud din"})) # we can pass only one argument while use print statment

print(data.update({"is man" : True}))

height= {"height": 163.3}

print(data.update(height))   #we can also store like this

print(data)

"""

# ==================== Sets in Python ===========================

# sets:collection of unordered(index) methoed are called sets

# each item in set are unique and immutable

num = {1,2,3,"asad"}  #we can also store string in set

print(num,type(num))

num2 = {1,2,3,2,4} #repeated elements stored only once otherwise set will ignore same values

print(num2)  

print(len(num2))#set will not count duplicate values while we check its legenth

null_set = set()    #empty set syntax

print(null_set)

# we can print legeenth of set

print(len(num))

# =============================== Set Methoeds ====================================

set7 = set()   #sets are mutable bcz we can't change in set values but we can add or remove values in the sets

set7.add(4)   #adds an element  

set7.add("asad shams ud din")  #pass string in set

set7.add((1,2,3,4,5,6,7)) #pass tuple in sets  

set7.add(4)   #same value cannot be enterd in set  

# note: we can't  pass list in set bcz our set is mutable

"""set7.add([0,9])"""   #error: unhashable type: 'list'

"""print(set7)"""

# imutable = unhashable mean immutable values

# hashing : change original value and convert into in another algorithem

set7.remove(4)  #remove an element

"""set7.remove(8)"""  #error bcz value does not exits

print(set7)

# empties the set (clear the set)  set.clear()

set7.clear()

print(set7)

print(len(set7))     #check the legenth of set after clear methoed it will return 0

print("this is new block of code ouput = ")

# pop methoed in set

# remove random values from sets

new_set = {23,56,78,90,21,66}

print(new_set.pop())  #set.pop()#it deos not take any argument

print(new_set.pop())

# ============================= IMP sets Methoeds =====================================

# Union methoed in sets

set8 = {2,4,5,6,7,8,}

set9 = {3,0,1,8}

union = set8.union(set9)      #combines both set values and returns new

print(union)

# Intersection methoed in sets

seta = {"a","d","f","g"}

setb = {"b","a","e","d"}

intersection = seta.intersection(setb)    #combines common values and returns new

print(intersection)

# ============================== Lets Practice ==================================

# Qno = 01

# store following words meaning in python dictionary

words = {

    "table" : ("a piecec of furniture","list of facts and figure"),

    "cat" : "a small animal"

}

print(words)

# Qno = 02

# you are given a list of subjects for students.Assume one classromm is required for 1 subject. How many class needed by all students

# "python","java","c++","python","javascript","java","python","java","c++","c"

subjects = {"python","java","c++","python","javascript","java","python","java","c++","c"}

need_classrom = len(subjects)

print("Room needs for every subjets are :  " ,need_classrom)

# Qno = 03

# WAP to enter marks of 3 subjects from the user and store them in dictionary. start with an empty dictionary & add one by one. Use subject name as a key & marks as a value

"""

sub_dictionary = {}

subject1 = int(input("enter your first subject marks = "))

subject2 = int(input("enter your seconed subject marks = "))

subject3 = int(input("enter your third subject marks = "))

sub_dictionary.update({"phy" : subject1})

sub_dictionary.update({"che" : subject2})

sub_dictionary.update({"eng" : subject3})

print(sub_dictionary)

"""

# Qno 04

# Figure out a way to stote 9 and 9.0 as a seprate value in the set (you can take help of built-in data types)

val = {9,"9.0"}  #first possible solution

# using built-in data type

set_09 = {

    ("float",9.0),

    ("integer",9)

}

print(val)

print(set_09)