
for element in [1,2,3]:
    print(element)

1
2
3


for element in (1,2,3):
    print(element)

1
2
3


for key in {'one':1,'two':2,'three':3}:
    print(key)

three
two
one


for char in "abc":
    print(char)

a
b
c


s = "123"
it = iter(s)
it

<str_iterator at 0x7fc78c071400>


next(it)

'1'


next(it)

'2'


next(it)

'3'


next(it)

---------------------------------------------------------------------------
StopIteration                             Traceback (most recent call last)
<ipython-input-9-2cdb14c0d4d6> in <module>()
----> 1 next(it)

StopIteration:


l = [1,2,3]
it = iter(l)
it

<list_iterator at 0x7fc78c0655f8>


next(it)

1


next(it)

2


next(it)

3


next(it)

---------------------------------------------------------------------------
StopIteration                             Traceback (most recent call last)
<ipython-input-14-2cdb14c0d4d6> in <module>()
----> 1 next(it)

StopIteration:


class Reverse:
    def __init__(self, data):
        self.data = data
        self.index = len(data)
    
    def __next__(self):
        if self.index == 0:
            raise StopIteration
        self.index = self.index-1
        return self.data[self.index]
    
    def __iter__(self):
        return self


rev = Reverse("spam")
it = iter(rev)
it

<__main__.Reverse at 0x7fc777774748>


next(it)

'm'


next(it)

'a'


next(it)

'p'


next(it)

's'


next(it)

---------------------------------------------------------------------------
StopIteration                             Traceback (most recent call last)
<ipython-input-21-2cdb14c0d4d6> in <module>()
----> 1 next(it)

<ipython-input-15-36508ed79b6d> in __next__(self)
      6     def __next__(self):
      7         if self.index == 0:
----> 8             raise StopIteration
      9         self.index = self.index-1
     10         return self.data[self.index]

StopIteration:


for char in Reverse("spam"):
    print(char)

m
a
p
s


L = [1,2,3]
it = iter(L)
it

<list_iterator at 0x7fc77777b390>


tuple(it)

(1, 2, 3)


mon = {'Jan':1,'Feb':2,'Mar':3,'Apr':4,'May':5,'Jun':6,
       'Jul':7,'Aug':8,'Sep':9,'Oct':10,'Nov':11,'Dec':12}
it = iter(mon)
it

<dict_keyiterator at 0x7fc77776fc28>


next(it)

'Mar'


next(it)

'Aug'


for key in mon:
    print(key,mon[key])

Mar 3
Aug 8
May 5
Nov 11
Jun 6
Feb 2
Oct 10
Apr 4
Dec 12
Jul 7
Sep 9
Jan 1


next(it)

'May'


for k,v in sorted(mon.items(),key=lambda x: x[1]):
    print(k,v)

Jan 1
Feb 2
Mar 3
Apr 4
May 5
Jun 6
Jul 7
Aug 8
Sep 9
Oct 10
Nov 11
Dec 12


%%writefile myfile.txt
Dies ist wieder
ein mehrzeiliger
Text

mit einigen

Leerzeilen

dazwischen

Writing myfile.txt


f = open("myfile.txt")
for line in f:
    if line.strip() != "":
        print(line,end="")

Dies ist wieder
ein mehrzeiliger
Text
mit einigen
Leerzeilen
dazwischen

NBA_02_Iteratoren¶

Iteratoren¶