list

问题 Let's say I have a list that contains 10,000+ proxies proxy_list = ['ip:port','ip:port',.....10,000+ items] How do I iterate it to get the proxies that works for my pc? Using the following code it is possible to find it , but takes 5*10,000 seconds to get completed. How would I iterate through the list faster? import requests result=[] for I in proxy_list: try: requests.get('http:\\www.httpbin.org\ip',proxies = {'https' : I, 'http' : I } ,timeout = 5) result.append(I) except: pass 回答1: You

问题 I am trying to take a list of names, alphabetize them and print them to a new list. Here is my code: names = [] newnames = [] with open("C:/names.txt", "r") as infile: for row in infile.readlines(): name = row.split() names.append(name) for x in sorted(names): newnames.append(x) print newnames f = open("C:/newnames.txt", "w") f.write("\n".join(str(x) for x in newnames)) f.close() my problem is that it prints fine except for the brackets: ['Bradley'] ['Harold'] ['Jackson'] ['Lincoln'] [

问题 I am trying to take a list of names, alphabetize them and print them to a new list. Here is my code: names = [] newnames = [] with open("C:/names.txt", "r") as infile: for row in infile.readlines(): name = row.split() names.append(name) for x in sorted(names): newnames.append(x) print newnames f = open("C:/newnames.txt", "w") f.write("\n".join(str(x) for x in newnames)) f.close() my problem is that it prints fine except for the brackets: ['Bradley'] ['Harold'] ['Jackson'] ['Lincoln'] [

问题 I have a code like below,when i print the list1 and list2 it shows same elements but i have added the 9 after the assignment of existing list1 to list2 so it should not show 9 in list2. list1=[1,2,3,4] list2=list1 list1.insert(4,9) print(list1) print(list2) please clear my doubt. 回答1: In python, a variable name is a reference to the underlying variable. Both list1 and list2 refer to the same list, so when you insert 9 into that list, you see the change in both. You need to make an explicit

问题 I'm going through the Python tutorial and have no idea why my code isn't working. I know I need to tell Python to print an integer manually but I have already put str(sum(ages)) . Can anyone tell me why this is happening? ages = ['24','34','51','36','57','21','28'] print('The oldest in the group is ' + str(max(ages)) + '.') print('The youngest in the group is ' + str(min(ages)) + '.') print('The combined age of all in the list is ' + str(sum(ages)) + '.') Error: File "list2.py", line 4, in

问题 I want to transfer a list of tuples: [(1, 3, 5), (2, 4, 6), (7, 8, 9)] to a list of dict (in order to create a pandas dataframe) which looks like: [{'index':1, 'match':1},{'index':1, 'match':3},{'index':1, 'match':5}, {'index':2, 'match':2}, {'index':2, 'match':4},{'index':2, 'match':6}, {'index':3, 'match':7},{'index':3, 'match':8},{'index':3, 'match':9}] For performance reasons I wanted to use a list and dict comprehension: [{'index':ind, 'match': } for ind, s in enumerate(test_set, 1)] How

问题 I have a question: I have a List Java that I have populated with different values. For example, I have: List<String[]> l = new ArrayList(); String[] lis = new String[3]; lis[0] = "A"; lis[1] = "B"; lis[2] = "C"; l.add(lis); and I have other values too. Now, I want to get the search in this list only the first field. For example, I want the A's indexOf. I have tried to write this code: int index = l.indexOf("A"); but I get -1 as return. I would like to know how I can access to a field of the

问题 I have a question: I have a List Java that I have populated with different values. For example, I have: List<String[]> l = new ArrayList(); String[] lis = new String[3]; lis[0] = "A"; lis[1] = "B"; lis[2] = "C"; l.add(lis); and I have other values too. Now, I want to get the search in this list only the first field. For example, I want the A's indexOf. I have tried to write this code: int index = l.indexOf("A"); but I get -1 as return. I would like to know how I can access to a field of the

问题 I have a question: I have a List Java that I have populated with different values. For example, I have: List<String[]> l = new ArrayList(); String[] lis = new String[3]; lis[0] = "A"; lis[1] = "B"; lis[2] = "C"; l.add(lis); and I have other values too. Now, I want to get the search in this list only the first field. For example, I want the A's indexOf. I have tried to write this code: int index = l.indexOf("A"); but I get -1 as return. I would like to know how I can access to a field of the

问题 def convBin(): cont = [] rest = [] dev = [] decimal = [] print("Ingrese el valor a convertir: ") valor = ast.literal_eval(input()) if isinstance(valor, int): while valor > 0: z = valor // 2 resto = valor%2 valor = valor // 2 cont.append(z) rest.append(resto) cont.reverse() rest.reverse() dev.append(cont[0]) x = 0 while x <= (len(rest) - 1): dev.append(rest[x]) x += 1 print(" ") print("Lista de devoluciones: ") print(dev) print("") elif isinstance(valor, float): a = valor // 1 b = valor % 1