Pyothonインタプリタ

Pythonインタプリタは対話的に処理を行わせることができる仕組みです。
Perlのone-linerみたいなことをホイホイと実行できる。

Python 3.6.0 (v3.6.0:41df79263a11, Dec 22 2016, 17:23:13) 
[GCC 4.2.1 (Apple Inc. build 5666) (dot 3)] on darwin
Type "copyright", "credits" or "license()" for more information.
>>> WARNING: The version of Tcl/Tk (8.5.9) in use may be unstable.
Visit http://www.python.org/download/mac/tcltk/ for current information.

>>> version
Traceback (most recent call last):
  File "<pyshell#1>", line 1, in <module>
    version
NameError: name 'version' is not defined
>>> --version
Traceback (most recent call last):
  File "<pyshell#2>", line 1, in <module>
    --version
NameError: name 'version' is not defined
>>> python
Traceback (most recent call last):
  File "<pyshell#3>", line 1, in <module>
    python
NameError: name 'python' is not defined
>>> ls
Traceback (most recent call last):
  File "<pyshell#4>", line 1, in <module>
    ls
NameError: name 'ls' is not defined
>>> 1 + 2
3
>>> 1-2
-1
>>> 4*5
20
>>> 7/5
1.4
>>> 3 ** 2
9
>>> 3 ** 50
717897987691852588770249
>>> 3 ** 1000
1322070819480806636890455259752144365965422032752148167664920368226828597346704899540778313850608061963909777696872582355950954582100618911865342725257953674027620225198320803878014774228964841274390400117588618041128947815623094438061566173054086674490506178125480344405547054397038895817465368254916136220830268563778582290228416398307887896918556404084898937609373242171846359938695516765018940588109060426089671438864102814350385648747165832010614366132173102768902855220001
>>> type(10)
<class 'int'>
>>> type(2.718)
<class 'float'>
>>> type("miki is beautiful")
<class 'str'>
>>> x = 10
>>> print(x)
10
>>>  x = 100
 
SyntaxError: unexpected indent
>>> x=100
>>> print(x)
100
>>> y = 3.14
>>> x * y
314.0
>>> type(x * y)
<class 'float'>
>>> a = [1,2,3,4,5,6] # list
>>> print(a)
[1, 2, 3, 4, 5, 6]
>>> print(a)
[1, 2, 3, 4, 5, 6]
>>> print(a) #一個前の>>>カーソルをクリックしてエンターキーを押すとコピーされる
[1, 2, 3, 4, 5, 6]
>>> print(a) #十字キーでも移動してエンターキーを押すとコピーされる
[1, 2, 3, 4, 5, 6]
>>> len(a)
6
>>> a[0] #first element access
1
>>> a[4] #4th element access
5
>>> a[4] #change 4th element value.
5
>>> a[4]=100 #change 4th element value.
>>> print(a) #changed value check
[1, 2, 3, 4, 100, 6]
>>> a[4]
100
>>> a[0:2]
[1, 2]
>>> a[0:100]
[1, 2, 3, 4, 100, 6]
>>> a[1:]
[2, 3, 4, 100, 6]
>>> a[:3]
[1, 2, 3]
>>> a[:100]
[1, 2, 3, 4, 100, 6]
>>> a[:-1]
[1, 2, 3, 4, 100]
>>> a[:-100]
[]
>>> a[:-2]
[1, 2, 3, 4]

結構楽しい。