python语言思想

python语言基础与应用
超级计算器

python语言解释器
为啥选用PYCHARM

create new project:
NANE+ 选择解释器
open ，选择打开文件或者加入project

注意对齐与缩进
注意字母大小写、空格
注意左右括号配对

错误是常见的，跟BUG和缺陷斗争得到过程
观察代码文本要求：注意上述的注意事项

对数据的抽象，对问题的处理采用的是对数据的抽象，避免处理其他杂糅的数据
何为大数据：

大数据分析处理语言
多种多样的数据类型
简单类型用来表示值
容器类型用来组织这些值


何为计算：
对现实世界处理和过程的抽象
控制流语句
定义语句：把一系列语句集合起来起一个名字 描述了一个包含一系列处理过程的计算单元 标签
基本类型：数值
整数类型：
双大小比较号 为比较判断 得到逻辑值 真或假
是很遵循数学逻辑
数的进制 所谓进制 9>0变两位加1 为10
整数的各种进制表示
0b 0o 0x
浮点数收到17位有限数字的限制
科学计数法：2.3*10^5
有效数字为2位

除了内置数学
还有math模块 面向整数浮点数
cmath 面向复数
基本类型：逻辑值
逻辑运算：双目运算 ：与 and 或or ，
单目运算：非not：
优先级not最高 and ，or最低
关于优先级往往会用括号进行提示，并非读代码人员运用所掌握的优先级方法转换

not None 变为真
字符数据类型：
三个连续单引号表示多行字符串 也就是包含了换行的位
转移符号：

字符串有哪些操作？：
小于0 的反方向编号

字符串是数据的本身
名字是数据的标签
名字和字符串是“名”与“值”之间的关系
常见的字符串操作：



序列：
字符串是一种序列

给数据的命名：

名字与变量
名字像一个标签
名字和数值之间的关联称为引用

设么是变量、何为变量？
与数值关联的名字也称作变量，


python语言是动态的语言
可以随时指向任何的类型，其他常见语言都是静态的
何为赋值？ 名字与数值关联的过程，称为给变量赋值，数值也称为数据对象

python 是语言大师创造的语言

上机练习时间：

要更注意错误，需要学会看错误，

Python 3.8.0 (tags/v3.8.0:fa919fd, Oct 14 2019, 19:37:50) [MSC v.1916 64 bit (AMD64)] on win32
Type "help", "copyright", "credits" or "license" for more information.
>>> 4.2+2.1==6.3
False
>>> print（4.2+2.1）
  File "<stdin>", line 1
    print（4.2+2.1）
          ^
SyntaxError: invalid character in identifier
>>> print(4+1)
5
>>> 4.2+2.1
6.300000000000001
>>> 1+3j
(1+3j)
>>> (1+2j).real
1.0
>>> (1+2j).imag
2.0
>>> import math
>>> dir(math)
['__doc__', '__loader__', '__name__', '__package__', '__spec__', 'acos', 'acosh', 'asin', 'asinh', 'atan', 'atan2', 'atanh', 'ceil', 'comb', 'copysign', 'cos', 'cosh', 'degrees', 'dist', 'e', 'erf', 'erfc', 'exp', 'expm1', 'fabs', 'factorial', 'floor', 'fmod', 'frexp', 'fsum', 'gamma', 'gcd', 'hypot', 'inf', 'isclose', 'isfinite', 'isinf', 'isnan', 'isqrt', 'ldexp', 'lgamma', 'log', 'log10', 'log1p', 'log2', 'modf', 'nan', 'perm', 'pi', 'pow', 'prod', 'radians', 'remainder', 'sin', 'sinh', 'sqrt', 'tan', 'tanh', 'tau', 'trunc']
>>> h=88
>>> m=g="dd"
>>> m
'dd'
>>> g
'dd'
>>> h
88
>>> type(h)
<class 'int'>
>>> type (m)
<class 'str'>
>>> len(m)
2
>>> n="qwertyuiop"
>>> n[1:6]
'werty'
>>> n*2
'qwertyuiopqwertyuiop'
>>> c=n*2
>>> c
'qwertyuiopqwertyuiop'
>>> c.isalpha
<built-in method isalpha of str object at 0x000001A0A09619E0>
>>> h.isdigit
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
AttributeError: 'int' object has no attribute 'isdigit'
>>> n=" ppq"
>>> c=n*3
>>> c
' ppq ppq ppq'
>>> c.split('')
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
ValueError: empty separator
>>> c.split(' ')
['', 'ppq', 'ppq', 'ppq']
>>> me="how are you, i an fine thankyou"
>>> me.split(" ")
['how', 'are', 'you,', 'i', 'an', 'fine', 'thankyou']
>>>  me[1]
  File "<stdin>", line 1
    me[1]
    ^
IndentationError: unexpected indent
>>> me[1:]
'ow are you, i an fine thankyou'
>>> me[1;2]
  File "<stdin>", line 1
    me[1;2]
        ^
SyntaxError: invalid syntax
>>> me[1:2]
'o'
>>> me[-1:-3]
''
>>> me[1:10]
'ow are yo'
>>> me[-3：-1]
  File "<stdin>", line 1
    me[-3：-1]
         ^
SyntaxError: invalid character in identifier
>>> me[-1:-3:1]
''
>>> me[-1:-10]
''
>>> me.upper
<built-in method upper of str object at 0x000001A0A0961940>
>>> me.upper()
'HOW ARE YOU, I AN FINE THANKYOU'
>>> "+++".join(me)
'h+++o+++w+++ +++a+++r+++e+++ +++y+++o+++u+++,+++ +++i+++ +++a+++n+++ +++f+++i+++n+++e+++ +++t+++h+++a+++n+++k+++y+++o+++u'
>>> "+".join(me,c,"nihaoma")
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
TypeError: join() takes exactly one argument (3 given)
>>> "+".join(me,c)
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
TypeError: join() takes exactly one argument (2 given)
>>> "+".join([me,c])
'how are you, i an fine thankyou+ ppq ppq ppq'
>>> "".join(["123456789"])
'123456789'
>>> "+".join("123456789")
'1+2+3+4+5+6+7+8+9'
>>> "+".join(["111"])
'111'
>>> me[0]
'h'
>>> me[-1]
'u'
>>> me[1]
'o'
>>> me[2]
'w'
>>> me.in("h"0
  File "<stdin>", line 1
    me.in("h"0
       ^
SyntaxError: invalid syntax
>>> me.in("h")
  File "<stdin>", line 1
    me.in("h")
       ^
SyntaxError: invalid syntax
>>> me.in"h"
  File "<stdin>", line 1
    me.in"h"
       ^
SyntaxError: invalid syntax
>>> me.in(h)
  File "<stdin>", line 1
    me.in(h)
       ^
SyntaxError: invalid syntax
>>> hex(33)
'0x21'
>>> oct(7)
'0o7'
>>> bin(7)
'0b111'
>>> 1.str()
  File "<stdin>", line 1
    1.str()
      ^
SyntaxError: invalid syntax
>>> str(1)
'1'
>>> int("abc")
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
ValueError: invalid literal for int() with base 10: 'abc'
>>> int(abc)
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
NameError: name 'abc' is not defined
>>> int(1)
1
>>> float(1)
1.0
>>> double(1)
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
NameError: name 'double' is not defined
>>> str(False)
'False'
>>> bool(1)
True
>>> bool(False)
False
>>> bool(false)
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
NameError: name 'false' is not defined
>>> int(sbc)
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
NameError: name 'sbc' is not defined
>>> 1 is None
<stdin>:1: SyntaxWarning: "is" with a literal. Did you mean "=="?
False
>>> 1 is None
<stdin>:1: SyntaxWarning: "is" with a literal. Did you mean "=="?
False
>>> me+c
'how are you, i an fine thankyou ppq ppq ppq'
>>> d=me+c
>>>
>>> d
'how are you, i an fine thankyou ppq ppq ppq'
>>> ord("A")
65
>>> chr("A")
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
TypeError: an integer is required (got type str)
>>> chr(65)
'A'
>>> chr(64)
'@'
>>> d.in
  File "<stdin>", line 1
    d.in
      ^
SyntaxError: invalid syntax
>>> d
'how are you, i an fine thankyou ppq ppq ppq'
>>> "h" in d
True
>>> p in d
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
NameError: name 'p' is not defined
>>> "w a" in d
True
>>> "wa"in d
False
>>> ord("猪")
29482
>>> chr(29482)
'猪'
>>> ord(d)
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
TypeError: ord() expected a character, but string of length 43 found
>>> ord("你好")
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
TypeError: ord() expected a character, but string of length 2 found
>>> len("你好“)
  File "<stdin>", line 1
    len("你好“)
             ^
SyntaxError: EOL while scanning string literal
>>> len("nihao")
5
>>> len("你好")
2
>>> d[1]
'o'
>>> s[-1]
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
NameError: name 's' is not defined
>>> d[-1]
'q'
>>> d[-1:-5]
''
>>> print(d[-1;-5])
  File "<stdin>", line 1
    print(d[-1;-5])
              ^
SyntaxError: invalid syntax
>>> d[-1:-5:]
''
>>> d[-1:]
'q'
>>> d[-2]
'p'
>>> d[::-1]
'qpp qpp qpp uoyknaht enif na i ,uoy era woh'
>>> d[-1:-5:-1]
'qpp '
>>> d.split(" ")
['how', 'are', 'you,', 'i', 'an', 'fine', 'thankyou', 'ppq', 'ppq', 'ppq']
>>> d.center
<built-in method center of str object at 0x000001A0A08D4BD0>
>>> d.center()
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
TypeError: center expected at least 1 argument, got 0
>>> center(d)
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
NameError: name 'center' is not defined
>>> d.center(30)
'how are you, i an fine thankyou ppq ppq ppq'
>>> "ppp".center(10)
'   ppp    '
>>> "ppp".center(100)
'                                                ppp                                                 '
>>> d.replace("how","mememe")
'mememe are you, i an fine thankyou ppq ppq ppq'
>>>
>>>> d.isdigit(
...
...
... )
False
>>> d.isdigit()
False
>>> d.isalpha()
False
>>> d.isalpha(h)
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
TypeError: isalpha() takes no arguments (1 given)
>>> f.isalpha("h")
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
NameError: name 'f' is not defined
>>> "123 ".isdigit()
False

数据收纳盒：
面临得需要处理的问题：如何使用? 名字[n]
列表，
元组（不可变序列）


字符串用“”
列表用[]
元组用()
列表的操作
容器，何为容器？是从简单数据类型引申出来的容器将简单类型数据组织起来

函数reversed不返回列表，而是返回一个迭代器。可使用list将返回的对象转换为列表。

>>> box["1",1,"a"]
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
NameError: name 'box' is not defined
>>> box[1]
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
NameError: name 'box' is not defined
>>> box=["ss","1",1]
>>> box
['ss', '1', 1]
>>> len.box
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
AttributeError: 'builtin_function_or_method' object has no attribute 'box'
>>> box.len
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
AttributeError: 'list' object has no attribute 'len'
>>> me.len
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
AttributeError: 'str' object has no attribute 'len'
>>> len(box)
3
>>> type(box)
<class 'list'>
>>> a1= list(m