Lists: storing many values

marks = [78, 85, 90, 62]

print(marks[0])       # First item
print(marks[-1])      # Last item
print(marks[1:3])     # A slice
print(len(marks))     # How many
print(sum(marks))     # Total
print(max(marks), min(marks))

78
62
[85, 90]
4
315
90 62

fruits = ["apple", "mango"]

fruits.append("banana")      # Add to the end
fruits.insert(0, "kiwi")     # Add at a position
print(fruits)

fruits[1] = "orange"         # Replace
fruits.remove("mango")       # Remove by value
last = fruits.pop()          # Remove and hand back the last item
print(fruits, last)

numbers = [3, 1, 2]
numbers.sort()
print(numbers)
numbers.reverse()
print(numbers)

['kiwi', 'apple', 'mango', 'banana']
['kiwi', 'orange'] banana
[1, 2, 3]
[3, 2, 1]

a = [1, 2, 3]
b = a            # NOT a copy: two names for one list
b.append(4)
print(a)         # a changed too!

c = a.copy()     # A real copy
c.append(5)
print(a)
print(c)

[1, 2, 3, 4]
[1, 2, 3, 4]
[1, 2, 3, 4, 5]

marks = [78, 35, 90, 22]

# The long way
doubled = []
for m in marks:
    doubled.append(m * 2)
print(doubled)

# The short way
print([m * 2 for m in marks])

# With a filter
print([m for m in marks if m >= 40])

[156, 70, 180, 44]
[156, 70, 180, 44]
[78, 90]