Indentations and not braces
less = []
greater = []
for x in [1, 2, 3, 4]:
if x < 3:
less.append(x)
else:
greater.append(x)
print("less = ", less, "greater = ", greater)
Variables and Argument Passing
a = [1, 2, 3]
a
b = a
b
a.append(4)
b
Conditionals: if else and elif
x = -5
if x < 0:
print("It's negative")
if int(x) < 0:
print("It's negative")
elif int(x) == 0:
print("Equal to zero")
elif 0 < int(x) < 5:
print("Positive but smaller than 5")
else:
print("Positive and larger than or equal to 5")
Loops
sequence = [1, 2, 0, 4, 6, 5, 2, 1]
total = 0
for value in sequence:
total += value
print(total)
Continue and break statements
sequence = [1, 2, None, 4, None, 5]
total = 0
for value in sequence:
if value is None:
continue
total += value
print(total)
sequence = [1, 2, 0, 4, 6, 5, 2, 1]
total_until_5 = 0
for value in sequence:
if value == 5:
break
total_until_5 += value
print(total_until_5)
Break only breaks the loop its in not all the loops its nested in
for i in range(4):
for j in range(4):
if j > i:
break
print((i, j))
While loops
x = 256
total = 0
while x > 0:
print(x)
if total > 500:
break
total += x
print(total)
x //= 2
Range
seq = [10, 20, 30, 40]
for i in range(len(seq)):
print("element %d: %d" %(i, seq[i]))
Enumerate
# enumerate function
l1 = ["eat", "sleep", "repeat"]
# creating enumerate objects
obj1 = enumerate(l1)
print ("Return type:", type(obj1))
print (list(enumerate(l1)))
sorted
a = [7, 1, 2, 6, 0, 3, 2]
sorted(a)
a
print(sorted("COP2000 Python Programming"))
zip
seq1 = ["Un", "Dos", "Tres"]
seq2 = ["one", "two", "three"]
zipped = zip(seq1, seq2)
list(zipped)
seq3 = [False, True]
list(zip(seq1, seq2, seq3))
for index, (a, b) in enumerate(zip(seq1, seq2)):
print(f"{index}: {a}, {b}") # https://realpython.com/python-f-strings/
reversed
list(reversed(range(10)))
Lambda function is an anon function
def apply_to_list(some_list, f):
return [f(x) for x in some_list]
ints = [2, 4, 6, 8, 1, 3, 5]
apply_to_list(ints, lambda x: x ** 2)
File and OS
getting and open files for manipulating it
! wget "https://www.gutenberg.org/files/76/76-0.txt" -O adventures.txt
! ( head -10 adventures.txt) > adventures10.txt
manipulation of the file
f = open("adventures10.txt", encoding="utf-8")
for line in f:
print(line)