dplyr tidyr擴大和總結特定的列

Question

我掙扎使用dplyr和tidyr採取DF這種形式：

myDf <- data.frame(id = c(1,1,1,1,2,2), 
        event = c('a','b','a','b','a','b'), 
        a_property = c(1,NA,2, NA, 3, NA), 
        b_property = c(NA,2,NA, 3, NA, 4)) 

> myDf 
id event a_property b_property 
1  a   1   NA 
1  b   NA   2 
1  a   2   NA 
1  b   NA   3 
2  a   3   NA 
2  b   NA   4  

，並轉換成以下所需的格式：

id count_event_a count_event_b sum_property_a sum_property_b 
1    2    2    3    5 
2    1    1    5    4 

Answer 1

多一點一般：

myDf %>% 
    gather(key, value, -id, -event) %>% 
    filter(!is.na(value)) %>% 
    group_by(id, event) %>% 
    summarise(count = n(), 
      sum = sum(value)) %>% 
    gather(key, value, -id, -event) %>% 
    unite(measure, key, event) %>% 
    spread(measure, value) 

Answer 2

myDf %>% 
    group_by(id) %>% 
    summarise(count_event_a = sum(!is.na(a_property)), 
      count_event_b = sum(!is.na(b_property)), 
      sum_property_a = sum(a_property, na.rm = TRUE), 
      sum_property_b = sum(b_property, na.rm = TRUE)) %>% 
    ungroup() 

您的示例中存在拼寫錯誤。答案應該是：

# A tibble: 2 × 5 
    id count_event_a count_event_b sum_property_a sum_property_b 
    <dbl>   <int>   <int>   <dbl>   <dbl> 
1  1    2    2    3    5 
2  2    1    1    3    4