Dictionary_func.md

python Dictionary methods

Invalid dictionary
Error: using a list as a key is not allowed hence use tuple
dictionary cannot have duplicate keys

my_dict = {
1: "Hello",
(1, 2): "Hello Hi",
}
print(my_dict)
a= my_dict.items()
print(a)

print(my_dict)

v=[] k=[] for i,j in zip(my_dict.values(),my_dict.keys()): v.append(i) k.append(j)

print(v,k)

country_capitals = {
"United States": "New York",
"Italy": "Naples",
"England": "London"
}

print(country_capitals)
print("=====================================")

change the value of "Italy" key to "Rome"

country_capitals["Italy"] = "Rome"

print(country_capitals)

country_capitals = {
"United States": "New York",
"Italy": "Naples"
}
print("=====================================")

add an item with "Germany" as key and "Berlin" as its value

country_capitals["Germany"] = "Berlin"

print(country_capitals)

print("=====================================")

delete item having "United States" key or also pop or popitem() remove last element

country_capitals = {
"United States": "New York",
"Italy": "Naples" ,
"mars":"planet",
"earth":"ours"
}
print(country_capitals)

print(country_capitals.pop('Italy'))
del country_capitals["United States"]
print(country_capitals.popitem())
print(country_capitals)

print("=====================================")

to copy and clear dict

a=country_capitals.copy()
print(a,country_capitals)
a.clear()
print(a,country_capitals)

print("=====================================")

update dictionary value

print(country_capitals)
country_capitals['mars']='solar'
print(country_capitals)

sort dictionary by val and key

a = sorted(dict_name.items(), key=lambda x:x[0]) # by Key
a = sorted(dict_name.items(), key=lambda x:x[1]) # by Value