Question

我有这种情况：

Animal  Date.1  Weight.1    Date.2  Weight.2    Date.3  Weight.3    Date.4  Weight.4
1       12/18/19    55      1/2/20  67                              6/6/20  101
2       12/18/19    64      1/3/20  69          2/4/20  80      
3       12/18/19    75                      
4                           1/3/20  85              
5       12/18/19    88      1/6/20  86          2/7/20  96          6/6/20  100

我想选择weight.1之后的最后一个重量，如下所示：

Animal  Date.last   Last Weight
1       6/6/20      101
2       2/4/20      80
3       NA          NA
4       1/3/20      85
5       6/6/20      100

对不起，我没有显示任何脚本，但我什至不知道从哪里开始。

Answer 1

在重塑为“长”格式后，这里是一个选项

TopAppBar(
            title = {
                Stack(modifier = Modifier.None) {
                    Align(alignment = Alignment.Center) {
                        Text(
                            text = "MyApp",
                            style = (+themeTextStyle { h6 }).withOpacity(0.7f)
                        )
                    }
                    Align(alignment = Alignment.CenterRight) {
                        CircleImageButton(
                            resource = Res.drawable.ic_action_reload,
                            onCLick = onRefreshClick
                        )
                    }
                }
            },
            color = Color.White
        )

数据

library(dplyr)    
library(tidyr)
library(stringr)
df1 %>% 
   pivot_longer(cols = -Animal, names_to = c(".value", "group"), 
        names_sep="[.]", values_drop_na = TRUE) %>%
   group_by(Animal) %>% 
   slice(n()) %>% 
   ungroup %>%
   mutate_at(vars(Date, Weight), ~ replace(., group == 1, NA)) %>%
   select(-group) %>%
   rename_at(2:3, ~ str_c(., 'last')) 
# A tibble: 5 x 3
#  Animal Datelast Weightlast
#   <int> <chr>         <int>
#1      1 6/6/20          101
#2      2 2/4/20           80
#3      3 <NA>             NA
#4      4 1/3/20           85
#5      5 6/6/20          100

Answer 2

在基数R中，您可以使用aggregate + reshape函数：

df1 <- reshape(`is.na<-`(df,df==""),2:ncol(df),idvar = "Animal",dir="long")

aggregate(cbind(Date,Weight)~Animal, df1,
           function(x)if(is.na(x[2])) NA else as.character(x[max(which(!is.na(x)))]),
           na.action = identity)

      Animal   Date Weight
1      1 6/6/20    101
2      2 2/4/20     80
3      3   <NA>   <NA>
4      4 1/3/20     85
5      5 6/6/20    100

在r的列中选择最后一个值

2 个答案:

数据