Question

我正在尝试在列表中打印列表。我知道，我之前发布了一个类似的问题 - Trouble printing a list within a list，但这是同一主题中的另一个问题，所以请不要将其标记为重复。我已将两个代码合并在一起，这是最终代码。在if语句中，我试图打印用户输入的某个客户的详细信息customer_number。代码搜索myList，Payments.txt已附加到[['E1234', '12/09/14', '440', 'A', '0']] Customer number: E1234 Date of payment: 12/09/14 Payment Amount: 440 Paid Amount: 0。代码可以完成所有这些，但问题是它多次打印出来;准确地说是6次：

print("Option A: Show a record\nOption Q: Quit")
decision = input("Enter A or Q: ")
myList = []

if decision == "A" or decision == "a":
    myFile = open("Payments.txt")
    customer_number = input("Enter a customer number to view their scores: ")
    record = myFile.readlines()
    for line in record:
        myList.append(line.strip().split(','))
        details = [x for x in myList if x[0] == customer_number]
        if details:
            print(details)
            print("Customer number: ", details[0][0])
            print("Date of payment: ", details[0][1])
            print("Payment Amount: ", details[0][2])
            print("Paid Amount: ", details[0][4])
    myFile.close()
    print(myList)

elif decision == "Q" or "q":
    exit

这是我的代码：

library(dplyr)
test %>% group_by(names, dates) %>% filter((n()>=2 & !is.na(values)) | n()==1)
Source: local data frame [8 x 3]
Groups: names, dates [8]

   names  dates values
  (fctr) (fctr)  (dbl)
1   Mike  04-26      1
2   Mike  04-27      2
3   John  04-28      4
4   John  04-27      5
5   John  04-26      6
6  David  04-01      1
7  David  04-02      2
8  David  04-03     NA

Answer 1

当您找到并打印答案时，您需要退出循环。

if details:
    print(details)
    print("Customer number: ", details[0][0])
    print("Date of payment: ", details[0][1])
    print("Payment Amount: ", details[0][2])
    print("Paid Amount: ", details[0][4])
    break

打印列表中的列表

1 个答案: