根据 R 中具有不同数据框输入的多个条件创建列类型答案

【问题标题】：Create a column Type based on several conditions with different dataframe inputs in R根据 R 中具有不同数据框输入的多个条件创建列类型
【发布时间】：2021-12-08 19:03:25
【问题描述】：

我有一个这样的数据框

id <- c(100,101,102,103,104,105,106,107,108,109,110)
state_code <- c("CA","CA","CA","CA","CA","CA","TX","TX","AZ","MN","CO")
df.sample <- data.frame(id,state_code,stringsAsFactors=FALSE)

我正在尝试对不同情况的数据框输入使用多个过滤器。

这是我正在使用的条件

如果整个数据帧的总行数

示例：

id <- c(100,101,102,103)
state_code <- c("CA","CA","TX","CA")
df.sample <- data.frame(id,state_code,stringsAsFactors=FALSE)

期望的输出

"Not enough ids"

如果总行数 >=5 并且如果 state_code >=5 中的任何单个状态的行，则创建列 Type = state_code 或 Type = "combined"

示例：

id <- c(100,101,102,103,104,105,106,107,108,109,110,111,112,113,114)
state_code <- c("CA","CA","CA","CA","CA","CA","TX","TX","TX","TX","TX","TX","AZ","MN","CO")
df.sample <- data.frame(id,state_code,stringsAsFactors=FALSE)

期望的输出

    id state_code     Type
   100         CA       CA
   101         CA       CA
   102         CA       CA
   103         CA       CA
   104         CA       CA
   105         CA       CA
   106         TX       TX
   107         TX       TX
   108         TX       TX
   109         TX       TX
   110         TX       TX
   111         TX       TX
   112         AZ Combined
   113         MN Combined
   114         CO Combined

如果总行数 >=5 并且如果 state_code are not >=5 中有任何单个州的行，则为所有值创建一个列 Type = "combined"

示例：

id <- c(100,101,102,103,104,105,106,107,108,109,110)
state_code <- c("CA","CA","CA","CA","TX","TX","TX","TX","AZ","MN","CO")
df.sample <- data.frame(id,state_code,stringsAsFactors=FALSE)

期望的输出

    id state_code     Type
   100         CA Combined
   101         CA Combined
   102         CA Combined
   103         CA Combined
   104         TX Combined
   105         TX Combined
   106         TX Combined
   107         TX Combined
   108         AZ Combined
   109         MN Combined
   110         CO Combined

我正在尝试为第一种情况这样做，但无法为其他人这样做

if(nrow(df.sample < 5){
    cat("Not enough ids")
}

如何将所有这些逻辑封装到一个代码中？有人能指出我正确的方向吗？

【问题讨论】：

如果总行数您是指整个数据帧还是每个代码？您的示例数据框（第一个）的期望结果是什么？
@Sotos，我刚刚编辑过。感谢您指出。这是整个数据框。

标签： r dplyr data.table tidyverse

【解决方案1】：

这行得通吗：

library(dplyr)

rowscount <- function(df, id_col){
  if(nrow(df) < 5)
    return('Not enough ids')
  else{
    op_df = df %>% group_by({{id_col}}) %>% mutate(Type = if_else(n() >= 5, 'state_code', 'combined'))
  return(op_df)
  }
}
rowscount(df.sample, state_code)
# A tibble: 11 x 3
# Groups:   state_code [5]
      id state_code Type      
   <dbl> <chr>      <chr>     
 1   100 CA         state_code
 2   101 CA         state_code
 3   102 CA         state_code
 4   103 CA         state_code
 5   104 CA         state_code
 6   105 CA         state_code
 7   106 TX         combined  
 8   107 TX         combined  
 9   108 AZ         combined  
10   109 MN         combined  
11   110 CO         combined  

id <- c(100,101,102,103)
state_code <- c("CA","CA","TX","CA")
df.sample <- data.frame(id,state_code,stringsAsFactors=FALSE)

rowscount(df.sample, state_code)
[1] "Not enough ids"

【讨论】：

【解决方案2】：

条件 2 和 3 相同，因此可以组合在一起。试试这个功能。

library(dplyr)

foo <- function(data){
  if(nrow(data) < 5 ) {
    return("Not enough ids")
  } else {
    data %>%
      group_by(state_code) %>%
      mutate(Type = case_when(n() < 5 ~ 'Combined', 
                              TRUE ~state_code)) %>%
      ungroup
  }
}

【讨论】：