python list

inicjowanie listy

l=[]
l=["a","b","c",1]
l[2] = 3          #podmiana elementu 3 w liscie 

l=list(range(10)) # lista z liczbami od zera do 10 szybaka do wygenerowania 

dodawanie wstawiane elementów

l=["a","b","c",1]
l.insert(3,3)   #1.pozycja wstawienia 2.element do wstawienia 
l.append()      #wstawianie elementu na koniec 

ilosc powtarzalnych elementow (count)

print("ilosc:",list.count(3))   #count()3 # ilosc powtarzajacych sie w liscie w tym przypadku chodzi ile powtarza sie 3 

index

l=["a","b","c",1]
print(lista.index("c")    # zwraca pozycje w tym przykladzie pozycja jest 2 

usuwanie elementu z listy

 l.remove("f") #usuwa pierwsze wystepnie f !!!

list Slicing

listname[start_index : end_index : step] - wzor 
end index ostatniego elementu który już nie wchodzi wycinka 

edytowanie list

my_list = [5, 8, 'Tom', 7.50, 'Emma']

# slice first four items
print(my_list[:4])
# Output [5, 8, 'Tom', 7.5]

# print every second element
# with a skip count 2
print(my_list[::2])
# Output [5, 'Tom', 'Emma']

# reversing the list
print(my_list[::-1])
# Output ['Emma', 7.5, 'Tom', 8, 5]

# Without end_value
# Stating from 3nd item to last item
print(my_list[3:])
# Output [7.5, 'Emma']

Adding elements to the list

append() function add item to the last place 
list.append("kupa")

insert(position,elemnt) --- fuction add element on the position 
list.insert(3, [25, 50, 75])

function del

enumerate

names = ['Jerry', 'Kramer', 'Elaine', 'George', 'Newman']
# Rewrite the for loop to use enumerate
indexed_names = []
for i,name in enumerate(names):
    index_name = (i,name)
    indexed_names.append(index_name) 
print(indexed_names)

# Rewrite the above for loop using list comprehension
indexed_names_comp = [(i,name) for i,name in enumerate(names)]
print(indexed_names_comp)

# Unpack an enumerate object with a starting index of one
indexed_names_unpack = [*enumerate(names,1)]
print(indexed_names_unpack)

map

names = ['Jerry', 'Kramer', 'Elaine', 'George', 'Newman']

# Use map to apply str.upper to each element in names
names_map  = map(str.upper,names)

# Print the type of the names_map
print(type(names_map))

# Unpack names_map into a list
names_uppercase = [*names_map]

# Print the list created above
print(names_uppercase)

python_zip

![image](https://github.com/stachulemko/doc/assets/88165736/21c1f55f-7136-4cdc-8c35-56f38f1b9086)
---jak uzywac zipa !!!

collection_counter

![image](https://github.com/stachulemko/doc/assets/88165736/99e84ebc-351a-4c3b-a578-fa36c7e79a0e)