·Python基础语法
@ Python之禅
>>> import this
Beautiful is better than ugly. # 优美胜于丑陋(Python以编写优美的代码为目标) Explicit is better than implicit. # 明了胜于晦涩(优美的代码应当是明了的,命名规范,风格相似) Simple is better than complex. # 简洁胜于复杂(优美的代码应当是简洁的,不要有复杂的内部实现) Complex is better than complicated. # 复杂胜于凌乱(如果复杂不可避免,那代码间也不能有难懂的关系,要保持接口简洁) Flat is better than nested. # 扁平胜于嵌套(优美的代码应当是扁平的,不能有太多的嵌套) Sparse is better than dense. # 间隔胜于紧凑(优美的代码有适当的间隔,不要奢望一行代码解决问题) Readability counts. # 可读性很重要(优美的代码是可读的) Special cases aren‘t special enough to break the rules. Although practicality beats purity. # 即便假借特例的实用性之名,也不可违背这些规则(这些规则至高无上) Errors should never pass silently. Unless explicitly silenced. # 不要包容所有错误,除非你确定需要这样做(精准地捕获异常,不写except:pass风格的代码) In the face of ambiguity, refuse the temptation to guess. # 当存在多种可能,不要尝试去猜测 There should be one-- and preferably only one --obvious way to do it. # 而是尽量找一种,最好是唯一一种明显的解决方案(如果不确定,就用穷举法) Although that way may not be obvious at first unless you‘re Dutch. # 虽然这并不容易,因为你不是 Python 之父(这里的Dutch是指Guido) Now is better than never. Although never is often better than *right* now. # 做也许好过不做,但不假思索就动手还不如不做(动手之前要细思量) If the implementation is hard to explain, it‘s a bad idea. If the implementation is easy to explain, it may be a good idea. # 如果你无法向人描述你的方案,那肯定不是一个好方案;反之亦然(方案测评标准) Namespaces are one honking great idea -- let‘s do more of those! # 命名空间是一种绝妙的理念,我们应当多加利用(倡导与号召)
@ 交互式编程
交互式编程不需要创建脚本文件,而是直接通过Python解释器的交互模式进来编写代码。下面我们来打开python自带的交互式编程客户端,打印一个hello,world!
@ 脚本式编程
通过脚本参数调用解释器开始执行脚本,直到脚本执行完毕。当脚本执行完成后,解释器不再有效。所有Python文件将以.py为扩展名。
让我们用记事本写一个print("hello,world !")。并把后缀名改为hello.py,把hello.py放到D:\Desktop
" win+r快速打开运行窗口" >>> "输入 ‘cmd‘ 打开命令窗口" >>> "输入 d: 按回车(进入d盘)" >>> "输入 cd d:\desktop 按回车(进入desktop工作目录)" >>> "运行python hello.py+回车" >>> 打印结果如下:
@ python文本编辑器
Geany官网:http://geany.org/(界面友好,适合新手)
pychrm官网:https://www.jetbrains.com/pycharm/download/#section=windows(选择社区免费版)
Anaconda官网:https://www.anaconda.com/download/(丘比特笔记本,继承环境。可以边记笔记边打代码)
@ python的字符编码
第一种:
#!/usr/bin/env python # _*_ coding:utf-8 _*_
第二种:
#!/usr/bin/env python # -*- coding:utf-8 -*-
第三种:
#!/usr/bin/env python # coding:utf-8
@ python的注释
单行注释: