239 lines
3.1 KiB
Markdown
239 lines
3.1 KiB
Markdown
# 原创
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： Python数据结构（一）——Python数据类型
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# Python数据结构（一）——Python数据类型
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## 回顾Python数据类型
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本系列需要用到的源码：[Python数据结构类封装](https://download.csdn.net/download/ds19991999/10571330)
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>
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Python支持面向对象的编程模式，这意味这Python在解决问题的过程中重点是数据.
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### 基本类型
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```
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False or True
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```
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```
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True
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```
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```
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not (False or True)
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```
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```
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False
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```
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```
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myList = [1,2,3,4]
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A = [myList]*3
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print(A)
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myList[2]=45
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print(A)
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```
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```
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[[1, 2, 3, 4], [1, 2, 3, 4], [1, 2, 3, 4]]
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[[1, 2, 45, 4], [1, 2, 45, 4], [1, 2, 45, 4]]
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```
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```
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# 与sort方法合用有效果
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myList.sort()
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myList
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```
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```
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[1, 2, 4, 45]
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```
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```
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myList.reverse()
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print myList
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```
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```
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[45, 4, 2, 1]
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```
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```
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myName = 'dsdshahahads'
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myName.split('s')
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```
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```
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['d', 'd', 'hahahad', '']
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```
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```
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{3,6,"cat",4.5,False,6,6,6,6,6,6,6}
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```
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```
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{False, 3, 4.5, 6, 'cat'}
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```
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### 输入与输出
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```
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aName = input("Please enter your name ")
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print("Your name in all capitals is",aName.upper(),
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"and has length", len(aName))
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```
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```
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Please enter your name 'ds'
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Your name in all capitals is 'DS' and has length 4
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```
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```
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# Python3支持，Python2不支持
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print("Hello","World", sep = "***")
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print("Hello","World", end = "***")
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```
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```
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Hello***World
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Hello World***
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```
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### 控制结构
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### 异常
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```
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import math
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try:
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anumber = int(input("Please enter an integer "))
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print(math.sqrt(anumber))
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except:
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print("Bad Value for square root")
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print("Using absolute value instead")
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print(math.sqrt(abs(anumber)))
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```
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```
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Please enter an integer -3
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Bad Value for square root
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Using absolute value instead
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1.73205080757
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```
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```
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import math
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try:
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anumber = int(input("Please enter an integer "))
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print(math.sqrt(anumber))
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except Exception as msg:
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print msg
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```
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```
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Please enter an integer -33
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math domain error
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```
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### 定义函数
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```
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def f(x):
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x *= x
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if not x < 100:
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return x
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else:
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return f(x)
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```
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```
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f(5)
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```
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```
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625
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```
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```
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f(f(3))
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```
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```
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43046721
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```
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### 类
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```
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def gcd(m,n):
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"""取余的公约数求法"""
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while m%n != 0:
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m,n = n,m%n
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return n
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class Fraction:
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def __init__(self,top,bottom):
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self.num = top
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self.den = bottom
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def __str__(self):
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return str(self.num)+"/"+str(self.den)
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def show(self):
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print(self.num,"/",self.den)
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def __add__(self,otherfraction):
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newnum = self.num*otherfraction.den + \
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self.den*otherfraction.num
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newden = self.den * otherfraction.den
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common = gcd(newnum,newden)
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return Fraction(newnum//common,newden//common)
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def __eq__(self, other):
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"""
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覆盖__eq__方法，通过相同的值创建深相等,而不是相同的引用
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即"=="，返回bool值
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"""
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firstnum = self.num * other.den
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secondnum = other.num * self.den
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return firstnum == secondnum
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x = Fraction(1,2)
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y = Fraction(2,3)
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print(x+y)
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print(x == y)
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```
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```
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7/6
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False
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```
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### 面向对象编程详见专题笔记
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### 总结
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