PYTHON LISTS

L
ISTS

Access Lists Items
list1 = ["abc", 34, True, 40, "male"]
print(list1)

['abc', 34, True, 40, 'male']

print(list1[-1],list1[0])

male abc

print(list1[-3:],list1[3:])

[True, 40, 'male'] [40, 'male']

print(list1[:-3],list1[:3])

['abc', 34] ['abc', 34, True]

print(list1[-4:-1],list1[1:4])

[34, True, 40] [34, True, 40]

if 34 in list1:
  print("Yes, '34' is in the fruits list")

Yes, '34' is in the fruits list

Change Lists Items
list1[1] = "def"
print("List :",list1)

List : ['abc', 'def', True, 40, 'male']

list1[1:3] = ["blackcurrant", "watermelon"]
print("List :",list1)

List : ['abc', 'blackcurrant', 'watermelon', 40, 'male']

list1[0:5] =["watermelon"]
print(list1)

['watermelon']

Add Lists Items
list1.append("orange")
print(list1)

['watermelon', 'orange']

list1.insert(-3,"bananna")
print(list1)

['bananna', 'watermelon', 'orange']

thislist = ["apple", "banana", "cherry"]
thistuple = ("kiwi", "apple")
list1.extend(thislist)
print(list1)

['bananna', 'watermelon', 'orange', 'apple', 'banana', 'cherry']

list1.extend(thistuple)
print(list1)

['bananna', 'watermelon', 'orange', 'apple', 'banana', 'cherry', 'kiwi', 'apple']

Remove Lists Items
list1.remove("apple")
print(list1)

['bananna', 'watermelon', 'orange', 'banana', 'cherry', 'kiwi', 'apple']

list1.pop(1)
print(list1)

['bananna', 'orange', 'banana', 'cherry', 'kiwi', 'apple']

list1.pop()
print(list1)

['bananna', 'orange', 'banana', 'cherry', 'kiwi']

del list1[0]
print(list1)

['orange', 'banana', 'cherry', 'kiwi']

Loop Lists Items
for x in list1:
  print(x)

orange
banana
cherry
kiwi

for k in range(len(list1)):
  print(list1[k])

orange
banana
cherry
kiwi

i = 0
while i < len(list1):
   print(list1[i])
  i = i + 1

orange
banana
cherry
kiwi

[print(j) for j in list1]

orange
banana
cherry
kiwi

Lists Comprehension
newlist = []
newlist.extend(list1)
print(newlist)

['orange', 'banana', 'cherry', 'kiwi']

newlist = []
for x in list1:
   if "a" in x:
   newlist.append(x)
print(newlist)

['orange', 'banana']

print([x for x in list1 if "e" in x])

['orange', 'cherry']

print([x for x in range(10) if x < 2])

[0, 1]

print([x for x in list1])

['orange', 'banana', 'cherry', 'kiwi']

print(['hello' for x in list1])

['hello', 'hello', 'hello', 'hello']

print([x if x != "banana" else "orange" for x in list1])

['orange', 'orange', 'cherry', 'kiwi']

Sort Lists
list1.sort()
print(list1)

['banana', 'cherry', 'kiwi', 'orange']

list1.sort(reverse = True)
print(list1)

['orange', 'kiwi', 'cherry', 'banana']

list1.reverse()
print(list1)

['banana', 'cherry', 'kiwi', 'orange']

def myfunc(n):
  return abs(n - 50)
thislist = [100, 50, 65, 82, 23]
thislist.sort(key = myfunc)
print(thislist)

[50, 65, 23, 82, 100]

list1.sort(key = str.upper)
print(list1)

['banana', 'cherry', 'kiwi', 'orange']

Copy Lists
thislist = list1.copy()
print(thislist)

['banana', 'cherry', 'kiwi', 'orange']

thislist = list(list1)
print(thislist)

['banana', 'cherry', 'kiwi', 'orange']

Join Lists
list1 = ["a", "b" , "c"]
thislist = [1, 2, 3]
list1.extend(thislist)
print(list1)

['a', 'b', 'c', 1, 2, 3]

list2 = list1 + thislist
print(list2)

['a', 'b', 'c', 1, 2, 3, 1, 2, 3]

list1.clear()
print("List Cleared:",list1)

List Cleared: []

del list1 It will be deleted.