根据其他/以前的列名设置列名，可能使用 apply() 或 for 循环

Question

我有一个大型数据集，其中每 5 列对应于 1 条动脉的测量值，但只有五列中的第一列被命名。一个例子：

df <- structure(list("agatston", "area", "volume", "density", "mass", 
                     "agatston", "area", "volume", "density", "mass", "agatston", 
                     "area", "volume", "density", "mass"), 
                .Names = c("Artery_1", NA, NA, NA, NA, "Artery_2", NA, NA, NA, NA, "Artery_3", NA, NA, NA, NA), 
                row.names = c(NA, -1L), 
                class = c("tbl_df", "tbl", "data.frame"))

看起来像这样：

df

# A tibble: 1 x 15
  Artery_1 ``    ``     ``      ``    Artery_2 ``    ``     ``      ``    Artery_3 ``    ``     ``      ``   
  <chr>    <chr> <chr>  <chr>   <chr> <chr>    <chr> <chr>  <chr>   <chr> <chr>    <chr> <chr>  <chr>   <chr>
1 agatston area  volume density mass  agatston area  volume density mass  agatston area  volume density mass 

我正在尝试使用 for 循环或 apply() 来使用最新的非缺失列名填充缺失的列名。我想要实现的目标如下所示：

# A tibble: 1 x 15
  Artery_1 Artery_1 Artery_1 Artery_1 Artery_1 Artery_2 Artery_2 Artery_2 Artery_2 Artery_2 Artery_3 Artery_3 Artery_3 Artery_3 Artery_3
  <chr>    <chr>    <chr>    <chr>    <chr>    <chr>    <chr>    <chr>    <chr>    <chr>    <chr>    <chr>    <chr>    <chr>    <chr>   
1 agatston area     volume   density  mass     agatston area     volume   density  mass     agatston area     volume   density  mass 

有什么帮助吗？

编辑： 作为下一步，我想通过将列与它下面的行的名称组合来使列 non_unique，从而产生以下输出：

 # A tibble: 1 x 15
  Artery_1_agatson Artery_1_area Artery_1_volume Artery_1_density Artery_1_mass Artery_2_agatson Artery_2_area Artery_2_volume
  <chr>            <chr>         <chr>           <chr>            <chr>         <chr>            <chr>         <chr>          
1 agatston         area          volume          density          mass          agatston         area          volume         
# ... with 7 more variables: Artery_2_density <chr>, Artery_2_mass <chr>, Artery_3_agatson <chr>, Artery_3_area <chr>,
#   Artery_3_volume <chr>, Artery_3_density <chr>, Artery_3_mass <chr>

Answer 1

基础 R 解决方案：

names(df) <- paste(
  na.omit(names(df))[cumsum(!(is.na(names(df))))],
  df[1,,drop=TRUE],
  sep = "_"
)

或者删除第一行：

clean_df <- setNames(
  df[-1,],
  paste(
    na.omit(names(df))[cumsum(!(is.na(names(df))))],
    df[1,,drop=TRUE],
    sep = "_"
  )
)

Answer 2

您可以使用zoo::na.locf 替换NA 值。

names(df) <- zoo::na.locf(names(df))
names(df)

# [1] "Artery_1" "Artery_1" "Artery_1" "Artery_1" "Artery_1" "Artery_2"
# [7] "Artery_2" "Artery_2" "Artery_2" "Artery_2" "Artery_3" "Artery_3"
#[13] "Artery_3" "Artery_3" "Artery_3"```

但是，列名相同不是一个好习惯，因此您可以使用make.unique 使列名唯一。

names(df) <- make.unique(zoo::na.locf(names(df)))
names(df)

# [1] "Artery_1"   "Artery_1.1" "Artery_1.2" "Artery_1.3" "Artery_1.4"
# [6] "Artery_2"   "Artery_2.1" "Artery_2.2" "Artery_2.3" "Artery_2.4"
#[11] "Artery_3"   "Artery_3.1" "Artery_3.2" "Artery_3.3" "Artery_3.4"

---

要将列与第一行合并，我们可以使用

names(df) <- paste(zoo::na.locf(names(df)), df[1, ], sep = '_')
names(df)

# [1] "Artery_1_agatston" "Artery_1_area"     "Artery_1_volume"  
# [4] "Artery_1_density"  "Artery_1_mass"     "Artery_2_agatston"
# [7] "Artery_2_area"     "Artery_2_volume"   "Artery_2_density" 
#[10] "Artery_2_mass"     "Artery_3_agatston" "Artery_3_area"    
#[13] "Artery_3_volume"   "Artery_3_density"  "Artery_3_mass"    

然后可能使用df <- df[-1, ] 删除第一行。