Python2

安裝pycharm專業版,不要漢化python

要想寫的代碼支持linux和2.0版本須要在開頭加上註釋linux

#/usr/bin/env pythongit

#-*- coding:utf-8 -*-api

運算符app

  結果是值ide

    算數運算spa

      a = 10*10code

    賦值運算orm

      a = a+1    即a+=1對象

  結果是布爾值(返還真或者假)

    比較運算

      a = 1>5

    邏輯運算

      a = 1>6 or 1==1

    成員運算

      a  = "tom" in "l"

基本數據類型

str用法:

 首字母變大寫

test = "tom"
v = test.capitalize()
print(v)
# 結果:Tom
全部的變小寫,有兩種方式,casefold和lower
test = "TOM"
v = test.casefold()
v = test.lower()
print(v)
#結果:tom
設置寬度,並將內容居中,*表明吧剩下的20個填充
test = "tom"
v = test.center(20,"*")
print(v)
# 結果:********tom*********
去字符串中尋找,尋找子序列出現的次數
test = "tomtomtomtom"
v = test.count("to")
# print(v)
以什麼什麼開頭什麼什麼結尾
test = "tomjerry"
v = test.endswith("to")  #不是以to結尾,返回值爲false
v = test.startswith("to")#是以to開頭,返回值爲True
print(v)
從開始日後找,找到第一個後,獲取其未知
test = "tomjerry"
v = test.find("p")
print(v)
 結果爲3 從第三個開始出現J若是找不到會返回值-1
test = "tomjerry"
print(test.index("j"))#若是找不到j會報錯
格式化,將一個字符串中的佔位符替換爲指定的值
test = "name{n},age{a}"
v = test.format(n="tom",a=106)
print(v)
結果:nametom,age106
字符串中是否只包含字母和數字
test = "tom19"
v = test.isalnum() 結果爲true
print(v)
斷句
test = "1234567\t9"
v = test.expandtabs(6)
print(v,len(v))
結果:1234567     9 13
字符串中是否包含字母漢字
test = "湯姆jerry"
v = test.isalpha()
print(v)
結果ture
是否包含數字
test = ""
v1 = test.isdecimal() #阿拉伯
v2 = test.isdigit()  #阿拉伯 ②
v3 = test.isnumeric()  #阿拉伯 ② 二
print(v1,v2,v3)
是否存在不可顯示的字符
#\t 製表符
#\n 換行
test = "tom\njerry\ttom\njerry\t"
v= test.isprintable()
print(v)
# 結果false 由於存在\n \t
判斷是否全是空格
test = " "
v = test.isspace()
print(v)
# 結果true
判斷是不是標題
test = "Tom and Jerry"
v1 = test.istitle()  # 結果: False
print(v1)  # v2 = test.title()  #
print(v2)  #結果:Tom And Jerry 變成標題格式
v3 = v2.istitle()
print(v3) #結果:ture
將字符串中的每個元素按照指定分隔符進行拼接
test = "tomjerry"
v= "_".join(test)
print(v)
# 結果:t_o_m_j_e_r_r_y
判斷是否所有是大小寫 和 轉換爲大小寫
test = "tOM"
v1 = test.islower()
v2 = test.lower()
print(v1, v2)
v1 = test.isupper()
v2 = test.upper()
print(v1,v2)
移除指定字符串
test = "tom"
#v = test.lstrip("t")  去掉t
v= test.strip("9")
print(v)
對應關係替換
test = "tomjerry"
test1 = "12345678"
v ="jason,enbo"
m = str.maketrans("tomjerry","12345678")
new_v = v.translate(m)
print(new_v)
分割爲三部分
test = "tomjerry"
v = test.partition("e")#('t', 'o', 'mjerry')
v1 = test.rpartition("e")
print(v)
分割爲指定個數
test = "tomjerry"
v = test.split("m",2) #'to', 'jerry's=吧m去掉剩下的分爲兩部分
print(v)
只能根據true false是否保留換行
test = "tom\njerry\nnatasha"
v = test.splitlines(False) #['tom', 'jerry', 'natasha']
print(v)
# test = "backend 1.1.1.1"
# v = test.startswith("b") 是否以b開頭
# v = test.endswith("1")是否以1結尾 返回true和false值
# print(v)
大小寫轉換
# test = "Tom"
# v = test.swapcase() #tOM  大小寫轉換
# print(v)
字母,數字,下劃線
# a = "tom_231"
# v= a.isidentifier() #判斷字母數字下劃線 true或者false
# print(v)
將指定字符串替換爲新的字符串
# test = "tom"
# #v = test.replace("tom","jerry") #將tom替換爲jerry
# print(v)
七個經常使用的:
join split find strip upper lower reolace
for循環:
# name = "tom" #一個一個字符輸出 t
# for test in name:              o
#     print(test)                m
# text = [5]
# index = 0
# while index <len(text):
#     v = text[index]
#     print(v)
#     index+=1
# print("========")
索引下標就是 tom 012 中的012就是索引 0對應t 1對應o 2對應m
# text = "tom"
# v = text[2]
# print(v)
切片
# text = "tom"  去除1和2 的值
# v = text[1:3]
# print(v)
獲取長度 len 獲取當前字符串有幾個字符組成
# text = "tom"
# v = len(text) #3個
# print(v)
range獲取連續或者不連續的數字 只有for循環的時候才顯示
# v = range(0,100,5)  #0 5 10 15 20 。。。
# for item in v:
#     print(item)
字符串一旦建立不可修改,一旦修改或者拼接,都會從新生成字符串
# text = "tom"
# age = "20"
# info = text + age
# print(info)
# #結果tom20
list列表
# li = [12,34,56,78,"tom"]
# #li.append(5) #追加
# #li.append("jerry")
# li.append([123,456]) #裏面再追加列表
# print(li)
#li = ["tom",123,"jerry",123]
# li.clear() #清除整個列表
#v = li.copy()#結果['tom', 123] copy拷貝命令
#v = li.count(123) #計算123出現的次數 2次
#li.extend(["natasha",123]) #擴展
#li = [0,456,789,123]
#v = li.index(123) #獲取123的位置,從左到右開始尋找
#li.insert(0,123) #在第一個插入123 0表明第一個
#li.remove(123) #刪除123
#li.reverse()#翻轉
#li.sort() [列表只能有數字才能排序]
#print(li)
#列表中能夠嵌套任何類型:[123,"tom",[0,[tom]]]
#列表中的元素能夠是數字,字符串,列表,布爾值。。。。全部的元素
#li = [123,"tom",True,456]
#print(li[3]) #索引取值第四個值
#print(li[0:2]) #切片取值
# for item in li: #也能夠循環
#     print(item)
# li = [123,"tom",True,456]
# #li[0] = 789 #修改,把123修改爲789 0表明第一個
# #del li[0:2] #刪除前兩個元素,也能夠刪除第一個
# print(li
字符串轉換成列表
# test = "name"
# li = list(test) #結果['n', 'a', 'm', 'e']把字符串指定成列表
# print(li)
列表換成字符串:既有數字又有字符串須要些for循環
# li = [123,"dsdas"]
# r = str(li)
# #print(li)
# s = ""
# for i in li:
#     s = s+str(i)

#     print(s)
#只有字符串的話用join
# li = ["ddd","ddd","ddd"]
# v= "".join(li)
# print(v)
元祖,元素不可修改,不能增長或者刪除
# tu = (11,22,33,44)# tu.count(22),獲取指定元素在元組中出現的次數
# v = tu.index(22)
# print(v)
索引
# v = tu[0]
# print(v)
切片
# v = tu[0:2]
# print(v)
能夠被for循環,可迭代對象
# for item in tu:
#     print(item)
轉換
# s = "asdfasdf0"
# li = ["asdf","asdfasdf"]
# tu = ("asdf","asdf")
#
# v = tuple(s)
# print(v)

# v = tuple(li)
# print(v)

# v = list(tu)
# print(v)

# v = "_".join(tu)
# print(v)

# li = ["asdf","asdfasdf"]
# li.extend((11,22,33,))
# print(li)
元組的一級元素不可修改/刪除/增長
# tu = (111,"alex",(11,22),[(33,44)],True,33,44,)
# # 元組,有序。
# # v = tu[3][0][0]
# # print(v)
# # v=tu[3]
# # print(v)
# tu[3][0] = 567
# print(tu)
字典
根據序列,建立字典,並指定統一的值
# v = dict.fromkeys(["k1",123,"999"],123)
# print(v)
刪除並獲取值
 
 
dic = {'k1': 123, 123: 123, '999': 123}
v = dic.pop("k1")
print(v) #獲取你刪除的值
print(dic)# 刪除後的字典
 
設置值,
已存在,不設置,獲取當前key對應的值
不存在,設置,獲取當前key對應的值
dic = {'k1': 123, 123: 123, '999': 123}
v = dic.setdefault("k1","123")
print(v,dic)
更新
# dic = {'k1': 123, 123: 123, '999': 123}
# dic.update({"k3":"v3"})
# print(dic)
字典的value能夠是任何值
# info = {
#     "k1": 18,
#     "k2": True,
#     "k3": [
#         11,
#         [],
#         (),
#         22,
#         33,
#         {
#             'kk1': 'vv1',
#             'kk2': 'vv2',
#             'kk3': (11,22),
#         }
#     ],
#     "k4": (11,22,33,44)
# }
# print(info)
布爾值(1,0)、列表、字典不能做爲字典的key
# info ={
#     1: 'asdf',
#     "k1": 'asdf',
#     True: "123",
#     # [11,22]: 123
#     (11,22): 123,
#     # {'k1':'v1'}: 123
#
# }
# print(info)
字典無序
# info = {
#     "k1": 18,
#     "k2": True,
#     "k3": [
#         11,
#         [],
#         (),
#         22,
#         33,
#         {
#             'kk1': 'vv1',
#             'kk2': 'vv2',
#             'kk3': (11,22),
#         }
#     ],
#     "k4": (11,22,33,44)
# }
# print(info)
索引方式找到指定元素
#info = {
#     "k1": 18,
#     2: True,
#     "k3": [
#         11,
#         [],
#         (),
#         22,
#         33,
#         {
#             'kk1': 'vv1',
#             'kk2': 'vv2',
#             'kk3': (11,22),
#         }
#     ],
#     "k4": (11,22,33,44)
# }
# # v = info['k1']
# # print(v)
# # v = info[2]
# # print(v)
# v = info['k3'][5]['kk3'][0]
# print(v)
字典支持 del 刪除
# info = {
#     "k1": 18,
#     2: True,
#     "k3": [
#         11,
#         [],
#         (),
#         22,
#         33,
#         {
#             'kk1': 'vv1',
#             'kk2': 'vv2',
#             'kk3': (11,22),
#         }
#     ],
#     "k4": (11,22,33,44)
# }
# del info['k1']
#
# del info['k3'][5]['kk1']
# print(info
for循環
# dict
# info = {
#     "k1": 18,
#     2: True,
#     "k3": [
#         11,
#         [],
#         (),
#         22,
#         33,
#         {
#             'kk1': 'vv1',
#             'kk2': 'vv2',
#             'kk3': (11,22),
#         }
#     ],
#     "k4": (11,22,33,44)
# }
# for item in info:
#     print(item)
#
# for item in info.keys():
#     print(item)

# for item in info.values():
#     print(item)

# for item in info.keys():
#     print(item,info[item])

# for k,v in info.items():
#     print(k,v)

# True 1  False 0
# info ={
#     "k1": 'asdf',
#     True: "123",
#     # [11,22]: 123
#     (11,22): 123,
#     # {'k1':' v1'}: 123
#
# }
# print(info)

 

整理
# 1、數字
# int(..)
# 2、字符串
# replace/find/join/strip/startswith/split/upper/lower/format
# tempalte = "i am {name}, age : {age}"
# # v = tempalte.format(name='alex',age=19)
# v = tempalte.format(**{"name": 'alex','age': 19})
# print(v)
# 3、列表
# append、extend、insert
# 索引、切片、循環
# 4、元組
# 忽略
# 索引、切片、循環         以及元素不能被修改
# 5、字典
# get/update/keys/values/items
# for,索引

# dic = {
#     "k1": 'v1'
# }

# v = "k1" in dic
# print(v)

# v = "v1" in dic.values()
# print(v)
# 6、布爾值
# 0 1
# bool(...)
# None ""  () []  {} 0 ==> Fals
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