Python Advanced (2023-01-15 - 2024-01-17)

a = 42

type(a)

int

Die Function dir() wird verwendet, um die attribute von a anzuzeigen

dir(a)

['__abs__',
 '__add__',
 '__and__',
 '__bool__',
 '__ceil__',
 '__class__',
 '__delattr__',
 '__dir__',
 '__divmod__',
 '__doc__',
 '__eq__',
 '__float__',
 '__floor__',
 '__floordiv__',
 '__format__',
 '__ge__',
 '__getattribute__',
 '__getnewargs__',
 '__getstate__',
 '__gt__',
 '__hash__',
 '__index__',
 '__init__',
 '__init_subclass__',
 '__int__',
 '__invert__',
 '__le__',
 '__lshift__',
 '__lt__',
 '__mod__',
 '__mul__',
 '__ne__',
 '__neg__',
 '__new__',
 '__or__',
 '__pos__',
 '__pow__',
 '__radd__',
 '__rand__',
 '__rdivmod__',
 '__reduce__',
 '__reduce_ex__',
 '__repr__',
 '__rfloordiv__',
 '__rlshift__',
 '__rmod__',
 '__rmul__',
 '__ror__',
 '__round__',
 '__rpow__',
 '__rrshift__',
 '__rshift__',
 '__rsub__',
 '__rtruediv__',
 '__rxor__',
 '__setattr__',
 '__sizeof__',
 '__str__',
 '__sub__',
 '__subclasshook__',
 '__truediv__',
 '__trunc__',
 '__xor__',
 'as_integer_ratio',
 'bit_count',
 'bit_length',
 'conjugate',
 'denominator',
 'from_bytes',
 'imag',
 'is_integer',
 'numerator',
 'real',
 'to_bytes']

Syntax

a = 42
if a == 42:
    print('yay')

yay

if a == 42:
  print('yay')

yay

DocStrings

# the function foo foos's a bar
# and returns the square of it
def foo(bar):
    return bar**2

def foo(bar):
    """the function foo foos's a bar
    and returns the square of it"""
    return bar**2

type(foo)

function

foo.__doc__

"the function foo foos's a bar\n    and returns the square of it"

help(foo)

Help on function foo in module __main__:

foo(bar)
    the function foo foos's a bar
    and returns the square of it

Type System

a = 42
type(a)

int

b = 43

a + b

85

c = 'abc'

def maximum(l, r):
    if l < r:
        return r
    return l

maximum(1,2)

2

try:
    maximum(1, '2')
except Exception as e:
    print(type(e), e)

<class 'TypeError'> '<' not supported between instances of 'int' and 'str'

maximum(1.2, 2)

2

def maximum_number(l, r):
    if l < r:
        return r
    return l

try:
    maximum_number(1, '2')
except Exception as e:
    print(type(e), e)

<class 'TypeError'> '<' not supported between instances of 'int' and 'str'

try:
    maximum_number(1, [1, 2, 3])
except Exception as e:
    print(type(e), e)

<class 'TypeError'> '<' not supported between instances of 'int' and 'list'

Variables

Tuple Unpacking

a = 42

a, b = 42, 666

a

42

b

666

(a, b) = (42, 666)

def foo():
    return 42, 666

rv = foo()

rv

(42, 666)

a, b = foo()

a, b

(42, 666)

tmp = a
a = b
b = tmp

a, b

(666, 42)

a, b = b, a

a, b

(42, 666)

Assignment Details

a = 42

id(a)

140526007219432

b = a

id(b)

140526007219432

b += 1

b

43

a

42

xxx = 666

xxx

666

del xxx

try:
    xxx
except Exception as e:
    print(type(e), e)

<class 'NameError'> name 'xxx' is not defined

d = {
    'a': 1,
    'b': 2,
}

d

{'a': 1, 'b': 2}

globals()['a']

42

a = 1234

globals()['a']

1234

del a

Infinity?

a = 2**64-1

a

18446744073709551615

bin(a)

'0b1111111111111111111111111111111111111111111111111111111111111111'

len(bin(a))

66

a += 1

bin(a)

'0b10000000000000000000000000000000000000000000000000000000000000000'

len(bin(a))

67

10**1000

10000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000

Datatype Conversions

a = '42'

type(a)

str

int(a)

42

try:
    int('42.0')
except Exception as e:
    print(type(e), e)

<class 'ValueError'> invalid literal for int() with base 10: '42.0'

str(42)

'42'

int('0x42', 16)

66

float(42)

42.0

float('42.666')

42.666

int(42.666)

42

Compound Datatypes

Lists

l = list()

type(l)

list

l = []

l = [1,2,'drei']

for elem in l:
    print(elem)

1
2
drei

l.append(4.0)

l

[1, 2, 'drei', 4.0]

l1 = [5, 6, 7]

l.extend(l1)

l

[1, 2, 'drei', 4.0, 5, 6, 7]

l2 = [8, 9, 10]

l.append(l2)

l

[1, 2, 'drei', 4.0, 5, 6, 7, [8, 9, 10]]

l[2]

'drei'

try:
    l[100]
except Exception as e:
    print(type(e), e)

<class 'IndexError'> list index out of range

try:
    l[100] = 666
except Exception as e:
    print(type(e), e)

<class 'IndexError'> list assignment index out of range

l += l2

l

[1, 2, 'drei', 4.0, 5, 6, 7, [8, 9, 10], 8, 9, 10]

6 in l

True

10 in l

True

666 in l

False

del l[2]

l

[1, 2, 4.0, 5, 6, 7, [8, 9, 10], 8, 9, 10]

l.pop()

10

l

[1, 2, 4.0, 5, 6, 7, [8, 9, 10], 8, 9]

Tuple

t = (1, 2, 'drei')

t[2]

'drei'

try:
    t.append(4.0)
except Exception as e:
    print(type(e), e)

<class 'AttributeError'> 'tuple' object has no attribute 'append'

2 in t

True

666 in t

False

Dictionary

d = {
    'one': 1,
    'two': 2,
}

type(d)

dict

d['one']

1

'one' in d

True

d['one'] = 1.0

try:
    d['three']
except Exception as e:
    print(type(e), e)

<class 'KeyError'> 'three'

del d['one']

d

{'two': 2}

d = {'one': 1, 'two': 2, 'three': 3}

for elem in d:
    print(elem)

one
two
three

for elem in d.keys():
    print(elem)

one
two
three

for elem in d.values():
    print(elem)

1
2
3

for elem in d.items():
    print(elem)

('one', 1)
('two', 2)
('three', 3)

a, b = 1, 2

for elem in d.items():
    # potschert
    k = elem[0]
    v = elem[1]
    print(k, v)

one 1
two 2
three 3

# Pythonic
for k, v in d.items():
    print(k, v)

one 1
two 2
three 3

Sets

s = set()

s= {}  # dict!

s = {1, 2, 'drei'}

for elem in s:
    print(elem)

1
2
drei

2 in s

True

s.add(4.0)

4.0 in s

True

try:
    s[3]
except Exception as e:
    print(type(e), e)

<class 'TypeError'> 'set' object is not subscriptable

s

{1, 2, 4.0, 'drei'}

print(s)

{1, 2, 'drei', 4.0}

enumerate()

l = [1, 2, 3, 4]

for elem in l:
    print(elem)

1
2
3
4

idx = 0
for elem in l:
    print(idx, elem)
    idx += 1

0 1
1 2
2 3
3 4

for elem in enumerate(l):
    print(elem)

(0, 1)
(1, 2)
(2, 3)
(3, 4)

for elem in enumerate(l):
    idx = elem[0]
    value = elem[1]
    print(idx, value)

0 1
1 2
2 3
3 4

for idx, value in enumerate(l):
    print(idx, value)

0 1
1 2
2 3
3 4

dict, and enumerate()

pairs = [('one', 1), ('two', 2)]

d = dict(pairs)
d

{'one': 1, 'two': 2}

l = ['zero', 'one']

for elem in l:
    print(elem)

zero
one

idx = 0
for elem in l:
    print(idx, elem)
    idx += 1

0 zero
1 one

for elem in enumerate(l):
    print(elem)

(0, 'zero')
(1, 'one')

for idx, value in enumerate(l):
    print(idx, value)

0 zero
1 one

dict(enumerate(l))

{0: 'zero', 1: 'one'}

while

summe = 0
num = 1
while num <= 100:
    summe += num
    num += 1
print(summe)

5050

sum(range(1, 101))    # so gehts auch

5050

import random
n_tries = 0
while True:
    n_tries += 1
    eyes = random.randrange(1, 7)
    if eyes == 6:
        print('hooray nach dem', n_tries, 'ten versuch')
        break

hooray nach dem 2 ten versuch

n_tries = 0
win = False
while n_tries < 10:
    n_tries += 1
    eyes = random.randrange(1, 7)
    if eyes == 6:
        win = True
        break
if win:
    print('win')
else:
    print('lose')

win

n_tries = 0
while n_tries < 10:
    n_tries += 1
    eyes = random.randrange(1, 7)
    if eyes == 6:
        print('win')
        break
else:
    print('lose')

win

range()

for elem in range(3):
    print(elem)

0
1
2

for elem in range(1, 4):
    print(elem)

1
2
3

for elem in range(1, 9, 2):
    print(elem)

1
3
5
7

l = [0,1,2]

for elem in l:
    print(elem)

0
1
2

for elem in range(3):
    print(elem)

0
1
2

r = range(3)
type(r)

range

print(r)

range(0, 3)

print(type(r))

<class 'range'>

for elem in r:
    print(elem)

0
1
2

r = range(3)

it = iter(r)

next(it)

0

next(it)

1

next(it)

2

try:
    next(it)
except Exception as e:
    print(type(e), e)

<class 'StopIteration'>

l = [0,1,2]

it = iter(l)

next(it)

0

next(it)

1

next(it)

2

try:
    next(it)
except Exception as e:
    print(type(e), e)

<class 'StopIteration'>

def even(maximum):
    rv = []
    num = 0
    while num < maximum:
        if num%2 == 0:
            rv.append(num)
        num += 1
    return rv

for elem in even(10):
    print(elem)

0
2
4
6
8

def even(maximum):
    print('start')
    num = 0
    while num < maximum:
        if num%2 == 0:
            print('suspend, produce', num)
            yield num
            print('wakeup')
        num += 1
    print('end')

nums = even(10)

print(nums)

<generator object even at 0x7fceb0516c20>

it = iter(nums)

next(it)

start
suspend, produce 0

0

next(it)

wakeup
suspend, produce 2

2

next(it)

wakeup
suspend, produce 4

4

next(it)

wakeup
suspend, produce 6

6

next(it)

wakeup
suspend, produce 8

8

try:
    next(it)
except Exception as e:
    print(type(e), e)

wakeup
end
<class 'StopIteration'>

cnt = 2
while cnt < 10:
    print(cnt)
    cnt += 1

2
3
4
5
6
7
8
9

for cnt in range(2, 10, 1):
    print(cnt)

2
3
4
5
6
7
8
9

Functions

def maximum(a: int, b: int) -> int:
    if a < b:
        return b
    return a

maximum('a', 'b')

'b'

maximum(1, 2)

2

maximum(1, 1.2)

1.2

try:
    maximum(1, '2')
except Exception as e:
    print(type(e), e)

<class 'TypeError'> '<' not supported between instances of 'int' and 'str'

1.0 == 1

True

f = 1.0

f.__eq__(1)

True

s = '1'

s.__eq__(1)

NotImplemented

i = 1

i.__eq__('1')

NotImplemented

id(maximum)

140525696085312

a = maximum

a(1, 2)

2

def create_print_function(msg):
    def inner():
        print(msg)
    return inner

joerg = create_print_function('Joerg')

joerg

<function __main__.create_print_function.<locals>.inner()>

joerg()

Joerg

References, (Im)mutability

a = 42
b = a

id(a)

140526007219432

id(b)

140526007219432

id(a) == id(b)

True

a is b

True

a == b

True

a += 1

id(a)

140526007219464

a is b

False

a == b

False

c

'abc'

del c

c = 666

id(c)

140525697462832

c += 1

id(c)

140525697462736

a = 42

id(a)

140526007219432

b = 42

id(b)

140526007219432

a = 666

id(a)

140525697463408

b = 666

id(b)

140525697463280

Shallow copy

a = [1,2,3]
b = a[:]

b.append(4)

b

[1, 2, 3, 4]

a

[1, 2, 3]

a = [1,2,[3,4,5],6, 7]
b = a[:]

b[2].append(666)

b

[1, 2, [3, 4, 5, 666], 6, 7]

a

[1, 2, [3, 4, 5, 666], 6, 7]

More About Strings

path = 'C:\no\name'
print(path)

C:
o
ame

line = '     \t  joerg     666\n'

match_expression = r'^\s*(\S+)\s*(\d+)\s*$'

import re

compiled_expression = re.compile(match_expression)

match = compiled_expression.search(line)

match.group(1)

'joerg'

match.group(2)

'666'

String Methods

s = 'mississippi'

s.count('ss')

2

s.find('ss')

2

s.find('ss', 3)

5

s.find('xxx')

-1

s.index('ss')

2

try:
    s.index('xxx')
except Exception as e:
    print(type(e), e)

<class 'ValueError'> substring not found

'XXX'.isupper()

True

'xxx'.islower()

True

'file.csv'.endswith('.csv')

True

'file.csv'.startswith('file')

True

'abc123'.isalnum()

True

'***'.center(100)

'                                                ***                                                 '

s

'mississippi'

s.rfind('ss')

5

'    xxx '.strip()

'xxx'

'   xxx '.rstrip()

'   xxx'

'   xxx '.lstrip()

'xxx '

'123   abc    1 2 3 '.strip(' 123')

'abc'

line = 'root:x:0:0:Super User:/root:/bin/bash\n'

line = line.rstrip()

line

'root:x:0:0:Super User:/root:/bin/bash'

elems = line.split(':')

elems[0]

'root'

name, passwd, uid, gid, descr, home, loginshell = line.split(':')

name

'root'

l = ['xxx', 'yyy', 'zzz']

joined_l = '-'.join(l)

l

['xxx', 'yyy', 'zzz']

joined_l

'xxx-yyy-zzz'

line = 'root:x:0:0:Super User:/root:/bin/bash\n'

line.split(':', 2)

['root', 'x', '0:0:Super User:/root:/bin/bash\n']

More About Lists

l = ['a', 'b', 'c']

l.append('d')

l

['a', 'b', 'c', 'd']

l.extend(['e', 'f'])

l

['a', 'b', 'c', 'd', 'e', 'f']

l.extend('ghi')

l

['a', 'b', 'c', 'd', 'e', 'f', 'g', 'h', 'i']

for c in 'ghi':
    print(c)

g
h
i

l.extend(range(3, 6))

l

['a', 'b', 'c', 'd', 'e', 'f', 'g', 'h', 'i', 3, 4, 5]

try:
    l.extend(666)
except Exception as e:
    print(type(e), e)

<class 'TypeError'> 'int' object is not iterable

try:
    for i in 666:
        print(i)
except Exception as e:
    print(type(e), e)

<class 'TypeError'> 'int' object is not iterable

rv = l.append(100)

type(rv)

NoneType

print(rv)

None

def f(): pass

rv = f()

print(rv)

None

More About Dictionaries

d = {'one': 1,
     'two': 2,
    }

rv = d.get('three')

print(rv)

None

rv = d.get('three')
if rv:
    print(rv)
else:
    print(3)

3

rv = d.get('three', 3)
print(rv)

3

rv = d.get('four')
if rv is not None:
    print(rv)
else:
    d['four'] = 4
    rv = d.get('four')
    print(rv)

4

rv = d.setdefault('five', 5)

print(rv)

5

d

{'one': 1, 'two': 2, 'four': 4, 'five': 5}

d2 = {'five': 5.5, 'six': 6, 'seven': 7.0}

d.update(d2)

d

{'one': 1, 'two': 2, 'four': 4, 'five': 5.5, 'six': 6, 'seven': 7.0}

list(d.keys())

['one', 'two', 'four', 'five', 'six', 'seven']

d[666] = 'crap'

d

{'one': 1,
 'two': 2,
 'four': 4,
 'five': 5.5,
 'six': 6,
 'seven': 7.0,
 666: 'crap'}

for elem in d:
    print(elem)

one
two
four
five
six
seven
666

for key in d.keys():
    print(key)

one
two
four
five
six
seven
666

for v in d.values():
    print(v)

1
2
4
5.5
6
7.0
crap

for elem in d.items():
    print(elem)

('one', 1)
('two', 2)
('four', 4)
('five', 5.5)
('six', 6)
('seven', 7.0)
(666, 'crap')

for k, v in d.items():
    print(k, v)

one 1
two 2
four 4
five 5.5
six 6
seven 7.0
666 crap

{}

{}

dict([('one', 1), ('two', 2)])

{'one': 1, 'two': 2}

{
    'one': 1,
    'two': 2,
}

{'one': 1, 'two': 2}

More About Sets

s = set()

s.add(42)

s.add('abc')

s

{42, 'abc'}

42 in s

True

try:
    s.add([1,2,'drei'])
except Exception as e:
    print(type(e), e)

<class 'TypeError'> unhashable type: 'list'

i = 666

hash(i)

666

i.__hash__()

666

l = [1, 2, 'drei']

try:
    hash(l)
except Exception as e:
    print(type(e), e)

<class 'TypeError'> unhashable type: 'list'

list.__dict__.get('__hash__')

Comprehensions (List, Dictionary, Set)

l = [0, 1, 2, 3, 4, 5]

l = list(range(6))

l

[0, 1, 2, 3, 4, 5]

squares = []
for elem in l:
    squares.append(elem**2)
squares

[0, 1, 4, 9, 16, 25]

squares = [elem**2 for elem in l]

squares

[0, 1, 4, 9, 16, 25]

even_squares = [elem**2 for elem in l if elem%2 == 0]

even_squares

[0, 4, 16]

l

[0, 1, 2, 3, 4, 5]

d = {}

for elem in l:
    d[elem] = elem**2

d

{0: 0, 1: 1, 2: 4, 3: 9, 4: 16, 5: 25}

{elem: elem**2 for elem in l}

{0: 0, 1: 1, 2: 4, 3: 9, 4: 16, 5: 25}

s = set()
for elem in l:
    s.add(elem**2)

s

{0, 1, 4, 9, 16, 25}

{elem**2 for elem in l}

{0, 1, 4, 9, 16, 25}

squares = []
for elem in l:
    squares.append(elem**2)
squares

[0, 1, 4, 9, 16, 25]

[elem**2 for elem in l]

[0, 1, 4, 9, 16, 25]

for num in [elem**2 for elem in l]:
    print(num)

0
1
4
9
16
25

for num in (elem**2 for elem in l):
    print(num)

0
1
4
9
16
25

File I/O

f = open('/etc/passwd', encoding='utf-8')

for line in f:
    print(line, end='')

root:x:0:0:Super User:/root:/bin/bash
bin:x:1:1:bin:/bin:/usr/sbin/nologin
daemon:x:2:2:daemon:/sbin:/usr/sbin/nologin
adm:x:3:4:adm:/var/adm:/usr/sbin/nologin
lp:x:4:7:lp:/var/spool/lpd:/usr/sbin/nologin
sync:x:5:0:sync:/sbin:/bin/sync
shutdown:x:6:0:shutdown:/sbin:/sbin/shutdown
halt:x:7:0:halt:/sbin:/sbin/halt
mail:x:8:12:mail:/var/spool/mail:/usr/sbin/nologin
operator:x:11:0:operator:/root:/usr/sbin/nologin
games:x:12:100:games:/usr/games:/usr/sbin/nologin
ftp:x:14:50:FTP User:/var/ftp:/usr/sbin/nologin
nobody:x:65534:65534:Kernel Overflow User:/:/usr/sbin/nologin
dbus:x:81:81:System Message Bus:/:/usr/sbin/nologin
apache:x:48:48:Apache:/usr/share/httpd:/sbin/nologin
tss:x:59:59:Account used for TPM access:/:/usr/sbin/nologin
systemd-coredump:x:998:998:systemd Core Dumper:/:/usr/sbin/nologin
systemd-network:x:192:192:systemd Network Management:/:/usr/sbin/nologin
systemd-oom:x:997:997:systemd Userspace OOM Killer:/:/usr/sbin/nologin
systemd-resolve:x:193:193:systemd Resolver:/:/usr/sbin/nologin
systemd-timesync:x:996:996:systemd Time Synchronization:/:/usr/sbin/nologin
qemu:x:107:107:qemu user:/:/sbin/nologin
polkitd:x:114:114:User for polkitd:/:/sbin/nologin
avahi:x:70:70:Avahi mDNS/DNS-SD Stack:/var/run/avahi-daemon:/sbin/nologin
geoclue:x:995:994:User for geoclue:/var/lib/geoclue:/sbin/nologin
nm-openconnect:x:994:993:NetworkManager user for OpenConnect:/:/sbin/nologin
usbmuxd:x:113:113:usbmuxd user:/:/sbin/nologin
gluster:x:993:992:GlusterFS daemons:/run/gluster:/sbin/nologin
rtkit:x:172:172:RealtimeKit:/proc:/sbin/nologin
pipewire:x:992:990:PipeWire System Daemon:/run/pipewire:/usr/sbin/nologin
saslauth:x:991:76:Saslauthd user:/run/saslauthd:/sbin/nologin
chrony:x:990:989:chrony system user:/var/lib/chrony:/sbin/nologin
dnsmasq:x:989:988:Dnsmasq DHCP and DNS server:/var/lib/dnsmasq:/usr/sbin/nologin
rpc:x:32:32:Rpcbind Daemon:/var/lib/rpcbind:/sbin/nologin
rpcuser:x:29:29:RPC Service User:/var/lib/nfs:/sbin/nologin
openvpn:x:988:987:OpenVPN:/etc/openvpn:/sbin/nologin
nm-openvpn:x:987:986:Default user for running openvpn spawned by NetworkManager:/:/sbin/nologin
colord:x:986:985:User for colord:/var/lib/colord:/sbin/nologin
unbound:x:985:984:Unbound DNS resolver:/var/lib/unbound:/sbin/nologin
abrt:x:173:173::/etc/abrt:/sbin/nologin
flatpak:x:984:982:Flatpak system helper:/:/usr/sbin/nologin
gdm:x:42:42:GNOME Display Manager:/var/lib/gdm:/usr/sbin/nologin
gnome-initial-setup:x:983:981::/run/gnome-initial-setup/:/sbin/nologin
vboxadd:x:982:1::/var/run/vboxadd:/sbin/nologin
sshd:x:74:74:Privilege-separated SSH:/usr/share/empty.sshd:/usr/sbin/nologin
tcpdump:x:72:72:tcpdump:/:/usr/sbin/nologin
jfasch:x:1000:1000:Jörg Faschingbauer:/home/jfasch:/bin/bash

f = open('/etc/passwd', encoding='utf-8')

f.read(5)

'root:'

f.read(5)

'x:0:0'

f.readline()

':Super User:/root:/bin/bash\n'

f.readline()

'bin:x:1:1:bin:/bin:/usr/sbin/nologin\n'

f.read()

'daemon:x:2:2:daemon:/sbin:/usr/sbin/nologin\nadm:x:3:4:adm:/var/adm:/usr/sbin/nologin\nlp:x:4:7:lp:/var/spool/lpd:/usr/sbin/nologin\nsync:x:5:0:sync:/sbin:/bin/sync\nshutdown:x:6:0:shutdown:/sbin:/sbin/shutdown\nhalt:x:7:0:halt:/sbin:/sbin/halt\nmail:x:8:12:mail:/var/spool/mail:/usr/sbin/nologin\noperator:x:11:0:operator:/root:/usr/sbin/nologin\ngames:x:12:100:games:/usr/games:/usr/sbin/nologin\nftp:x:14:50:FTP User:/var/ftp:/usr/sbin/nologin\nnobody:x:65534:65534:Kernel Overflow User:/:/usr/sbin/nologin\ndbus:x:81:81:System Message Bus:/:/usr/sbin/nologin\napache:x:48:48:Apache:/usr/share/httpd:/sbin/nologin\ntss:x:59:59:Account used for TPM access:/:/usr/sbin/nologin\nsystemd-coredump:x:998:998:systemd Core Dumper:/:/usr/sbin/nologin\nsystemd-network:x:192:192:systemd Network Management:/:/usr/sbin/nologin\nsystemd-oom:x:997:997:systemd Userspace OOM Killer:/:/usr/sbin/nologin\nsystemd-resolve:x:193:193:systemd Resolver:/:/usr/sbin/nologin\nsystemd-timesync:x:996:996:systemd Time Synchronization:/:/usr/sbin/nologin\nqemu:x:107:107:qemu user:/:/sbin/nologin\npolkitd:x:114:114:User for polkitd:/:/sbin/nologin\navahi:x:70:70:Avahi mDNS/DNS-SD Stack:/var/run/avahi-daemon:/sbin/nologin\ngeoclue:x:995:994:User for geoclue:/var/lib/geoclue:/sbin/nologin\nnm-openconnect:x:994:993:NetworkManager user for OpenConnect:/:/sbin/nologin\nusbmuxd:x:113:113:usbmuxd user:/:/sbin/nologin\ngluster:x:993:992:GlusterFS daemons:/run/gluster:/sbin/nologin\nrtkit:x:172:172:RealtimeKit:/proc:/sbin/nologin\npipewire:x:992:990:PipeWire System Daemon:/run/pipewire:/usr/sbin/nologin\nsaslauth:x:991:76:Saslauthd user:/run/saslauthd:/sbin/nologin\nchrony:x:990:989:chrony system user:/var/lib/chrony:/sbin/nologin\ndnsmasq:x:989:988:Dnsmasq DHCP and DNS server:/var/lib/dnsmasq:/usr/sbin/nologin\nrpc:x:32:32:Rpcbind Daemon:/var/lib/rpcbind:/sbin/nologin\nrpcuser:x:29:29:RPC Service User:/var/lib/nfs:/sbin/nologin\nopenvpn:x:988:987:OpenVPN:/etc/openvpn:/sbin/nologin\nnm-openvpn:x:987:986:Default user for running openvpn spawned by NetworkManager:/:/sbin/nologin\ncolord:x:986:985:User for colord:/var/lib/colord:/sbin/nologin\nunbound:x:985:984:Unbound DNS resolver:/var/lib/unbound:/sbin/nologin\nabrt:x:173:173::/etc/abrt:/sbin/nologin\nflatpak:x:984:982:Flatpak system helper:/:/usr/sbin/nologin\ngdm:x:42:42:GNOME Display Manager:/var/lib/gdm:/usr/sbin/nologin\ngnome-initial-setup:x:983:981::/run/gnome-initial-setup/:/sbin/nologin\nvboxadd:x:982:1::/var/run/vboxadd:/sbin/nologin\nsshd:x:74:74:Privilege-separated SSH:/usr/share/empty.sshd:/usr/sbin/nologin\ntcpdump:x:72:72:tcpdump:/:/usr/sbin/nologin\njfasch:x:1000:1000:Jörg Faschingbauer:/home/jfasch:/bin/bash\n'

f.read(1)

''

f = open('/etc/passwd', 'rb')

b = f.read(5)

type(b)

bytes

Data Science

import pandas

df = pandas.read_csv('meine-cpu.csv', delimiter=';')

df

	hwmon2	hwmon4	hwmon5	hwmon7	hwmon8
0	37.85	41.0	41.0	49.0	30.0
1	37.85	40.0	40.0	42.0	31.0
2	37.85	41.0	41.0	43.0	31.0
3	37.85	41.0	41.0	43.0	31.0
4	37.85	41.0	41.0	43.0	31.0
...	...	...	...	...	...
83	43.85	78.0	78.0	59.0	32.0
84	44.85	76.0	76.0	67.0	32.0
85	44.85	75.0	75.0	71.0	32.0
86	44.85	74.0	74.0	66.0	33.0
87	44.85	73.0	73.0	67.0	33.0

88 rows × 5 columns

df['hwmon2'][0:7]

0    37.85
1    37.85
2    37.85
3    37.85
4    37.85
5    37.85
6    37.85
Name: hwmon2, dtype: float64

df['hwmon7']

0     49.0
1     42.0
2     43.0
3     43.0
4     43.0
      ...
83    59.0
84    67.0
85    71.0
86    66.0
87    67.0
Name: hwmon7, Length: 88, dtype: float64

len(df)

88

x = range(88)

y = df['hwmon7']

import matplotlib.pyplot as plt

plt.plot(x, y)

[<matplotlib.lines.Line2D at 0x7fce70506000>]