self.dict[lastVal].add(index) self.dict[lastVal].remove(lastIndex) return exist def getRandom(self) -> int: """ Get a random element from the collection. """ index = random.randint(0, len(self.list) - 1) return self.list[index] 1. 2. 3. 4. 5. 6. 7. 8. 9. 10. 11. ...
The random library is a built-in Python library, i.e, you do not have to install it. You can directly import it. We will look at 3 different ways to select a random item from a list using the random library. 1. Random Index¶ importrandomnum_items=len(twitter_user_names)random_i...
"""将一颗色子掷6000次,统计每种点数出现的次数Author: 骆昊Version: 1.0"""importrandomf1=0f2=0f3=0f4=0f5=0f6=0for_inrange(6000):face=random.randrange(1,7)ifface==1:f1+=1elifface==2:f2+=1elifface==3:f3+=1elifface==4:f4+=1elifface==5:f5+=1else:f6+=1print(f'1点出...
random.choice()可以从任何序列,比如list列表中,选取一个随机的元素返回,可以用于字符串、列表、元组等。 random.sample()可以从指定的序列中,随机的截取指定长度的片断,不作原地修改。 ''' list_one=["name","age",18] choice_num=random.choice(list_one) print(choice_num) index_num=randint(1,1000)%l...
从集合中随机抽取元素(不放回) 1importmath2fromnumpyimport*345dataIndex=list(range(20))6print(dataIndex)7print('---')8foriinrange(20):9randIndex =random.choice(dataIndex)#go to 0 because of the constant10print(randIndex)11del(dataIndex[dataIndex.index(randIndex)])12print(dataIndex)13print...
1、list.append(obj):在列表末尾添加新的对象 2、list.count(obj):统计某个元素在列表中出现的次数 3、list.extend(seq):在列表末尾一次性追加另一个序列中的多个值(用新列表扩展原来的列表) 4、list.index(obj):从列表中找出某个值第一个匹配项的索引位置 ...
Let’s think about a simple example where we have a set of numbers contained in a list,and we would like to pick one of those numbers uniformly at random. 在本例中,我们需要使用的函数是random.choice,在括号内,我们需要一个列表。 The function we need to use in this case is random.choice...
import xlrd xlsx = xlrd.open_workbook('./3_1 xlrd 读取 操作练习.xlsx')# 通过sheet名查找:xlsx.sheet_by_name("sheet1")# 通过索引查找:xlsx.sheet_by_index(3)table = xlsx.sheet_by_index(0)# 获取单个表格值 (2,1)表示获取第3行第2列单元格的值value = table.cell_value(2, 1) print("...
如果你不想或不能命名索引,你可以在查询表达式中使用index指代 In [224]: df = pd.DataFrame(np.random.randint(n, size=(n, 2)), columns=list('bc')) In [225]: df Out[225]: b c 0 3 1 1 3 0 2 5 6 3 5 2 4 7 4 5 0 1 ...
con = cx_Oracle.connect('pythonhol/welcome@127.0.0.1/orcl') ver = con.version.split(".") print ver print ver.index("1") ver.remove("2") print ver ver1 = ["11", "g"] ver2 = ["R", "2"] print ver1 + ver2 con.close() 在命令行终端重新运行该脚本: python connect.py ind...