R（指标）中的条件语句基于匹配另一个数据集的值

Question

我有两个数据集

包含列水果的数据集1，customer_num

包含fruit2，customer_num

列的数据集2

因此，假设我使用customer_num作为joiner，将数据集1与数据集2进行左连接。现在我得到了一个包含fruit和fruit2作为列变量的数据集。

如何创建一个指示符来说明水果== fruit2然后1还是0？

Answer 1

如果ifelse最容易，假设它在同一个数据帧中。使用dplyr包的示例

    dataset1 %>%
    mutate(Match=ifelse(fruit==fruit2,1,0))

这将创建一个名为Match的列，如果匹配则执行1，如果不匹配则执行0

Answer 2

你可以这样做（我的例子）：

# I've created example of customer_num where I presumed that this are numbers
fruit <- data.frame(customer_num = c(1, 2, 3, 4, 5, 6))
fruit2 <- data.frame(customer_num = c(1, 2, 3, 10, 11, 12))

# Vector in data frame
df <- data.frame(fruit, fruit2)

# And match values / Indicator
dat<-within(df,match <- ifelse (fruit == fruit2,1,0))

# Output
  customer_num customer_num.1 customer_num
1            1              1            1
2            2              2            1
3            3              3            1
4            4             10            0
5            5             11            0
6            6             12            0