如何在R中获得分组计数(滚动总和)？

# 加载所需的包
library(dplyr)
library(tidyverse)

# 创建示例数据
data <- data.frame(variable1 = c("A", "B", "A", "B", "A"),
                   variable2 = c("X", "Y", "X", "Y", "Z"))

# 按照变量variable1和variable2进行分组计数
grouped_data <- group_by(data, variable1, variable2)
summary_data <- summarize(grouped_data, count = n())

# 打印结果
print(summary_data)

# A tibble: 4 x 3
# Groups:   variable1 [?]
  variable1 variable2 count
  <chr>     <chr>     <int>
1 A         X             2
2 A         Z             1
3 B         Y             2
4 B         Z             1

# 加载所需的包
library(zoo)

# 创建示例数据
data <- data.frame(variable1 = c("A", "A", "A", "B", "B"),
                   variable2 = c(1, 2, 3, 4, 5))

# 按照变量variable1进行分组，并计算滚动总和
grouped_data <- group_by(data, variable1)
summary_data <- summarize(grouped_data, rolling_sum = rollapply(variable2, width = 3, FUN = sum, align = "right", fill = NA))

# 打印结果
print(summary_data)

# A tibble: 5 x 3
# Groups:   variable1 [?]
  variable1 variable2 rolling_sum
  <chr>         <dbl>       <dbl>
1 A                 1          NA
2 A                 2          NA
3 A                 3           6
4 B                 4          NA
5 B                 5          NA