如何插入计数器来计算客户在r中的贷款数量？

Question

拥有一组拥有多笔贷款的借款人的数据集。我想插入一个计算每笔贷款的贷款计数器。下面是我想让柜台看的桌子。我还会创建一个新的列，显示借款者拥有的最大贷款数量。我还想插入两栏。一种识别每个借款人的第一笔贷款，另一种识别每个借款人的最后一笔贷款。请看下表

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Answer 1

假设您的贷款是有序的(例如，通过Loan_Date)，您可以使用tidyverse采取这种方法。使用group_by计算给定Customer_ID的贷款，然后使用row_number和n()确定所需的列值。

library(tidyverse)

df %>%
  group_by(Customer_ID) %>%
  mutate(LoanCounter = row_number(),
         MaxLoan = n(),
         FirstLoan = ifelse(row_number() == 1, 1, 0),
         LastLoan = ifelse(row_number() == n(), 1, 0))

输出

# A tibble: 9 x 7
# Groups:   Customer_ID [2]
  Customer_ID Customer_Account Loan_Date LoanCounter MaxLoan FirstLoan LastLoan
        <dbl>            <dbl>     <dbl>       <int>   <int>     <dbl>    <dbl>
1      100100             1001    200801           1       5         1        0
2      100100             1002    200902           2       5         0        0
3      100100             1003    201003           3       5         0        0
4      100100             1004    201105           4       5         0        0
5      100100             1005    201209           5       5         0        1
6      100102             2001    201805           1       4         1        0
7      100102             2006    201903           2       4         0        0
8      100102             2010    201905           3       4         0        0
9      100102              238    202002           4       4         0        1

数据

df <- structure(list(Customer_ID = c(100100, 100100, 100100, 100100, 
100100, 100102, 100102, 100102, 100102), Customer_Account = c(1001, 
1002, 1003, 1004, 1005, 2001, 2006, 2010, 238), Loan_Date = c(200801, 
200902, 201003, 201105, 201209, 201805, 201903, 201905, 202002
)), class = "data.frame", row.names = c(NA, -9L))