在将列表转换为数据框或数据时处理缺失信息 table

Dealing with missing information while converting a list into data frame or data table

相关,是否有任何方法可以将其中一些名称重复的命名元素列表转换为数据 table,其中 NA 值实际显示在数据中 table 按照它们在列表中出现的顺序?

例如:列表

testlist <- list("Blue", "405", "Truck", "400", "Car", "White", "500", "Truck")
testnames <- c("Color", "HP", "Type", "HP", "Type", "Color", "HP", "Type")
names(testlist) <- testnames

$Color
[1] "Blue"

$HP
[1] "405"

$Type
[1] "Truck"

$HP
[1] "400"

$Type
[1] "Car"

$Color
[1] "White"

$HP
[1] "500"

$Type
[1] "Truck"

可以更改为数据 table 使用:

dcast(setDT(melt(testlist))[, N:=1:.N, L1], N~L1, value.var='value')

但输出是这样的:

  N Color  HP  Type
1 1  Blue 405 Truck
2 2 White 400   Car
3 3  <NA> 500 Truck

当我想要的时候:

  N Color  HP  Type
1 1  Blue 405 Truck
2 2  <NA> 400   Car
3 3 White 500 Truck

有人对如何解决这个问题有建议吗?感谢您的帮助。

可能不是最佳解决方案,因为它使用了 while 循环。但是,使用 tidyr 或您最喜欢的其他整形包。

testlist <- c("Blue", "405", "Truck", "400", "Car", "White", "500", "Truck")
testnames <- c("Color", "HP", "Type", "HP", "Type", "Color", "HP", "Type")

df <- data.frame(names = testnames, attributes = testlist, stringsAsFactors = FALSE)



# need to count number of vehicles inside data frame

# initialise while loop counters
df_index = 1
vehicle_index = vector(mode = "integer", length = nrow(df))
vehicle_count = 1

# now loop through the data frame to find attributes 
# which belong to vehicle 1, 2, 3, etc...
while(df_index <= nrow(df)){
    if (sum(c("Color", "HP", "Type") == df$names[df_index:(df_index+2)]) == 3) {
        vehicle_index[df_index:(df_index+2)] <- vehicle_count
        df_index = df_index + 3
        vehicle_count = vehicle_count + 1
    } else if (sum(c("Color", "HP", "Type") %in% df$names[df_index:(df_index+1)]) == 2) {
        vehicle_index[df_index:(df_index+1)] <- vehicle_count
        df_index = df_index + 2
        vehicle_count = vehicle_count + 1
    } else {
        vehicle_index[df_index:(df_index)] <- vehicle_count
        df_index = df_index + 1
        vehicle_count = vehicle_count + 1
    }

}

# finally, label the vehicle attributes with the vehicle number,
# and spread the data.
df_final <- data.frame(df, vehicle_index = vehicle_index)

tidyr::spread(df_final, key = "names", value = "attributes")

一种方法是用正确的行数和正确的列数、名称和类型预分配 table,然后通过索引分配原始列表覆盖的单元格来填充它.

cns <- c('Color','HP','Type');
lcis <- match(names(testlist),cns);
lris <- c(1L,cumsum(diff(lcis)<=0L)+1L);
df <- as.data.frame(testlist[match(1:length(cns),lcis)],stringsAsFactors=F)[0,];
df[max(lris),] <- NA;
df;
##   Color   HP Type
## 1  <NA> <NA> <NA>
## 2  <NA> <NA> <NA>
## 3  <NA> <NA> <NA>
for (ci in 1:length(cns)) { m <- lcis==ci; df[lris[m],ci] <- do.call(c,testlist[m]); };
df;
##   Color  HP  Type
## 1  Blue 405 Truck
## 2  <NA> 400   Car
## 3 White 500 Truck

在我的解决方案中,我小心翼翼地分别处理每一列,如果输出中的不同列 table(对应于输入列表中不同的组件子集)具有不同的数据类型,这提供了潜在的好处,那么这些数据类型将被保留在最后的 table 中。这就是我为索引分配选择 for 循环的原因。对于只有字符类型的精确输入列表,这当然不是必需的,但无论如何我认为这是一个值得的目标。

中间变量的解释

  • cns 输出中的列名 table.
  • lcis 每个输入列表组件将在输出中具有的列索引 table。这是通过简单地将输入列表组件的名称与 cns.
  • 进行匹配来计算的
  • lris 每个输入列表组件将在输出中具有的行索引 table。这个变量的计算有点有趣并且是解决方案的核心。由于输入列表中的列表示不完整(IOW 在输入列表中可以有 "missing columns"),但您认为输入列表组件是根据它们在输出中的按行出现来排序的 [=96= 】,我们不能使用常规索引(比如将每三个组件作为一行),我们也不能使用任何单个列名作为每一行的标记,因为任何列都可以在任何行中丢失。根据我的想法,唯一正确的方法是确定输入列表中的低索引(或实际上是等索引)列何时紧接在高索引(或等索引)列之后出现,并将其作为换行符.因此,我们可以取 diff(lcis)<=0L 得到一个表示换行的逻辑向量,取 cumsum() 加 1 得到行索引,我们还必须手动添加 1 来完成向量。
  • ci 输出中的列索引 table。在 for 循环期间用于迭代每个输出列。
  • mfor 循环中的每个 ci 计算。一个逻辑向量,表示哪些输入列表组件属于当前列 ci。用于索引 lris(提取行索引进行分配)和输入列表本身(提取实际值进行分配)。

实际数据

我从 dropbox 中抓取了你的真实数据并将其存储为 testlist。以下是我的调查结果。

首先,我按照出现的顺序检查了唯一的组件名称,将它们设为 cns:

## first reasonable assumption about cns
cns <- unique(names(testlist));
cns;
##  [1] "Status"              "Make"                "Model"
##  [4] "Kilometres"          "Stock Number"        "Engine"
##  [7] "Number of Hours"     "Front axle"          "Rear axle"
## [10] "Suspension"          "Wheelbase"           "Transmission"
## [13] "Price"               "Style/Trim"          "Brakes"
## [16] "Mfg Exterior Colour" "Tires"               "Engine (HP)"
## [19] "Exterior Colour"

从中我们可以计算出一个新的暂定 lcis:

## examine lcis for ordering
lcis <- match(names(testlist),cns);
lcis;
##   [1]  1  2  3  4  5  6  7  8  9 10 11 12 13  1  2  3  4  5  6  7  8  9 10 11 12
##  [26] 13  1  2  3  4  5  6  7  8  9 10 11 12 13  1  2  3  4  5  6  7  8  9 10 11
##  [51] 12 13  1  2  3  4  5  6  7  8  9 10 11 12 13  1  2  3  4  5  6  7  8  9 10
##  [76] 11 12 13  1  2  3  4  5  6  7  8  9 10 11 12 13  1  2  3  4  5  6  7  8  9
## [101] 10 11 12 13  1  2  3  4  5  6  7  8  9 10 11 12 13  1  2  3  4  5  6  7  8
## [126]  9 10 11 12 13  1  2  3  4  5  6  7  8  9 10 11 12 13  1  2  3  4  5  6  7
## [151]  8  9 10 11 12 13  1  2  3  4 14 13  1  2  3  4  5  6  7  8  9 10 11 12 13
## [176]  1  2  3  4  5 15 16  6  8  9 10 17 11 18 12 19 13  1  2  3  4  5 15 16  6
## [201]  8  9 10 17 11 18 12 19 13

仔细观察上面的向量,我们可以看到它以1:13的许多规则重复开始。事实上,只有在向量的末尾,它才变得不规则,我们看到 14 后跟 13,16 后跟 6,10-11-12 与 17-18-19 交错,等等

但我们在这里可以做的一个重要观察是,向量似乎由 1 和 13 划定的组组成。换句话说,对于似乎具有某种规律性的所有范围(即使也存在一些不规则性) ,它们似乎以 1 开头,以 13 结尾。这一观察结果与您关于车辆数据中间无序的评论一致。让我们称之为 1/13 假设。

我们可以通过在这个 1/13 边界上拆分来更清楚地了解组:

## recognizing 1/13 consistency, split on it to see how each (possible) row looks under this assumption
split(lcis,cumsum(lcis==1L));
## $`1`
##  [1]  1  2  3  4  5  6  7  8  9 10 11 12 13
##
## $`2`
##  [1]  1  2  3  4  5  6  7  8  9 10 11 12 13
##
## $`3`
##  [1]  1  2  3  4  5  6  7  8  9 10 11 12 13
##
## $`4`
##  [1]  1  2  3  4  5  6  7  8  9 10 11 12 13
##
## $`5`
##  [1]  1  2  3  4  5  6  7  8  9 10 11 12 13
##
## $`6`
##  [1]  1  2  3  4  5  6  7  8  9 10 11 12 13
##
## $`7`
##  [1]  1  2  3  4  5  6  7  8  9 10 11 12 13
##
## $`8`
##  [1]  1  2  3  4  5  6  7  8  9 10 11 12 13
##
## $`9`
##  [1]  1  2  3  4  5  6  7  8  9 10 11 12 13
##
## $`10`
##  [1]  1  2  3  4  5  6  7  8  9 10 11 12 13
##
## $`11`
##  [1]  1  2  3  4  5  6  7  8  9 10 11 12 13
##
## $`12`
##  [1]  1  2  3  4  5  6  7  8  9 10 11 12 13
##
## $`13`
## [1]  1  2  3  4 14 13
##
## $`14`
##  [1]  1  2  3  4  5  6  7  8  9 10 11 12 13
##
## $`15`
##  [1]  1  2  3  4  5 15 16  6  8  9 10 17 11 18 12 19 13
##
## $`16`
##  [1]  1  2  3  4  5 15 16  6  8  9 10 17 11 18 12 19 13

现在,如果您 非常 仔细查看以上组,您会发现可以重新排序 cns,这样所有组都会升序排列。它们不会是连续的,但我为原始问题设计的解决方案不需要连续;所有必要的是升序。

例如,我们需要将第 14 列排在第 13 列之前,我们需要将第 15 和 16 列排在第 6、8、9 等列之前:

## recognizing the possibility of reordering to achieve perfect within-row ascending order, reorder cns to cns2
cns2 <- cns[c(1,2,3,4,14,5,15,16,6,7,8,9,10,17,11,18,12,19,13)];
cns2;
##  [1] "Status"              "Make"                "Model"
##  [4] "Kilometres"          "Style/Trim"          "Stock Number"
##  [7] "Brakes"              "Mfg Exterior Colour" "Engine"
## [10] "Number of Hours"     "Front axle"          "Rear axle"
## [13] "Suspension"          "Tires"               "Wheelbase"
## [16] "Engine (HP)"         "Transmission"        "Exterior Colour"
## [19] "Price"

现在我们可以重新计算 lcis,我现在将其称为 lcis2,并演示新的组订单:

## calculate lcis2 from cns2, and prove that we've successfully ordered each individual row under the 1/13 (now 1/19) break assumption
lcis2 <- match(names(testlist),cns2);
split(lcis2,cumsum(lcis2==1L));
## $`1`
##  [1]  1  2  3  4  6  9 10 11 12 13 15 17 19
##
## $`2`
##  [1]  1  2  3  4  6  9 10 11 12 13 15 17 19
##
## $`3`
##  [1]  1  2  3  4  6  9 10 11 12 13 15 17 19
##
## $`4`
##  [1]  1  2  3  4  6  9 10 11 12 13 15 17 19
##
## $`5`
##  [1]  1  2  3  4  6  9 10 11 12 13 15 17 19
##
## $`6`
##  [1]  1  2  3  4  6  9 10 11 12 13 15 17 19
##
## $`7`
##  [1]  1  2  3  4  6  9 10 11 12 13 15 17 19
##
## $`8`
##  [1]  1  2  3  4  6  9 10 11 12 13 15 17 19
##
## $`9`
##  [1]  1  2  3  4  6  9 10 11 12 13 15 17 19
##
## $`10`
##  [1]  1  2  3  4  6  9 10 11 12 13 15 17 19
##
## $`11`
##  [1]  1  2  3  4  6  9 10 11 12 13 15 17 19
##
## $`12`
##  [1]  1  2  3  4  6  9 10 11 12 13 15 17 19
##
## $`13`
## [1]  1  2  3  4  5 19
##
## $`14`
##  [1]  1  2  3  4  6  9 10 11 12 13 15 17 19
##
## $`15`
##  [1]  1  2  3  4  6  7  8  9 11 12 13 14 15 16 17 18 19
##
## $`16`
##  [1]  1  2  3  4  6  7  8  9 11 12 13 14 15 16 17 18 19

最后,我们可以 运行 整个解决方案,现在要小心使用 2 后缀的变量名:

## now we can apply the preallocate/fill-in solution using cns2 and lcis2
## will use lris2 and df2 just to be consistent
lris2 <- c(1L,cumsum(diff(lcis2)<=0L)+1L);
df2 <- as.data.frame(testlist[match(1:length(cns2),lcis2)],stringsAsFactors=F)[0,];
df2[max(lris2),] <- NA;
df2;
##    Status Make Model Kilometres Style.Trim Stock.Number Brakes Mfg.Exterior.Colour Engine Number.of.Hours Front.axle Rear.axle Suspension Tires Wheelbase Engine..HP. Transmission Exterior.Colour Price
## 1    <NA> <NA>  <NA>       <NA>       <NA>         <NA>   <NA>                <NA>   <NA>            <NA>       <NA>      <NA>       <NA>  <NA>      <NA>        <NA>         <NA>            <NA>  <NA>
## 2    <NA> <NA>  <NA>       <NA>       <NA>         <NA>   <NA>                <NA>   <NA>            <NA>       <NA>      <NA>       <NA>  <NA>      <NA>        <NA>         <NA>            <NA>  <NA>
## 3    <NA> <NA>  <NA>       <NA>       <NA>         <NA>   <NA>                <NA>   <NA>            <NA>       <NA>      <NA>       <NA>  <NA>      <NA>        <NA>         <NA>            <NA>  <NA>
## 4    <NA> <NA>  <NA>       <NA>       <NA>         <NA>   <NA>                <NA>   <NA>            <NA>       <NA>      <NA>       <NA>  <NA>      <NA>        <NA>         <NA>            <NA>  <NA>
## 5    <NA> <NA>  <NA>       <NA>       <NA>         <NA>   <NA>                <NA>   <NA>            <NA>       <NA>      <NA>       <NA>  <NA>      <NA>        <NA>         <NA>            <NA>  <NA>
## 6    <NA> <NA>  <NA>       <NA>       <NA>         <NA>   <NA>                <NA>   <NA>            <NA>       <NA>      <NA>       <NA>  <NA>      <NA>        <NA>         <NA>            <NA>  <NA>
## 7    <NA> <NA>  <NA>       <NA>       <NA>         <NA>   <NA>                <NA>   <NA>            <NA>       <NA>      <NA>       <NA>  <NA>      <NA>        <NA>         <NA>            <NA>  <NA>
## 8    <NA> <NA>  <NA>       <NA>       <NA>         <NA>   <NA>                <NA>   <NA>            <NA>       <NA>      <NA>       <NA>  <NA>      <NA>        <NA>         <NA>            <NA>  <NA>
## 9    <NA> <NA>  <NA>       <NA>       <NA>         <NA>   <NA>                <NA>   <NA>            <NA>       <NA>      <NA>       <NA>  <NA>      <NA>        <NA>         <NA>            <NA>  <NA>
## 10   <NA> <NA>  <NA>       <NA>       <NA>         <NA>   <NA>                <NA>   <NA>            <NA>       <NA>      <NA>       <NA>  <NA>      <NA>        <NA>         <NA>            <NA>  <NA>
## 11   <NA> <NA>  <NA>       <NA>       <NA>         <NA>   <NA>                <NA>   <NA>            <NA>       <NA>      <NA>       <NA>  <NA>      <NA>        <NA>         <NA>            <NA>  <NA>
## 12   <NA> <NA>  <NA>       <NA>       <NA>         <NA>   <NA>                <NA>   <NA>            <NA>       <NA>      <NA>       <NA>  <NA>      <NA>        <NA>         <NA>            <NA>  <NA>
## 13   <NA> <NA>  <NA>       <NA>       <NA>         <NA>   <NA>                <NA>   <NA>            <NA>       <NA>      <NA>       <NA>  <NA>      <NA>        <NA>         <NA>            <NA>  <NA>
## 14   <NA> <NA>  <NA>       <NA>       <NA>         <NA>   <NA>                <NA>   <NA>            <NA>       <NA>      <NA>       <NA>  <NA>      <NA>        <NA>         <NA>            <NA>  <NA>
## 15   <NA> <NA>  <NA>       <NA>       <NA>         <NA>   <NA>                <NA>   <NA>            <NA>       <NA>      <NA>       <NA>  <NA>      <NA>        <NA>         <NA>            <NA>  <NA>
## 16   <NA> <NA>  <NA>       <NA>       <NA>         <NA>   <NA>                <NA>   <NA>            <NA>       <NA>      <NA>       <NA>  <NA>      <NA>        <NA>         <NA>            <NA>  <NA>
for (ci in 1:length(cns2)) { m <- lcis2==ci; df2[lris2[m],ci] <- do.call(c,testlist[m]); };
df2;
##    Status          Make                                          Model Kilometres    Style.Trim Stock.Number Brakes Mfg.Exterior.Colour                  Engine Number.of.Hours                     Front.axle                      Rear.axle                     Suspension    Tires Wheelbase Engine..HP.                   Transmission Exterior.Colour    Price
## 1     New     Peterbilt                 367 Tri-Drive c/w 58'' Sleeper   3,360 km          <NA>        12949   <NA>                <NA> Cummins ISX15  (550 hp)              44  Dana Spicer D2000  (20,000lb) Dana T69-170    (wide track) t Peterbilt Air-Trak  (66,000lb)     <NA>     267''        <NA>  RTLO18918B  Fuller (18 speed)            <NA> 7,770
## 2     New      Kenworth                               T800 T/A Tractor  82,230 km          <NA>        10720   <NA>                <NA>   Cummins ISX15 (550hp)           2,712 Dana Spicer D2000  (20,000 lb) Dana D46-170HPW (46,000 lb) ta Neway ADZ252    (52,000lb) Air     <NA>     244''        <NA> Fuller 18 spd main AT1202 2 sp            <NA> 9,500
## 3     New      Kenworth            T800 Tandem Tractor w/ 38'' Sleeper  98,521 km          <NA>        10722   <NA>                <NA>   Cummins ISX15 (550hp)           2,790 Dana Spicer D2000  (20,000 lb) Dana D46-170HPW (46,000 lb) ta Neway ADZ252    (52,000lb) Air     <NA>     244''        <NA> Fuller 18 spd main AT1202 2 sp            <NA> 9,500
## 4    Used      Kenworth           W900 Tri-Drive Sleeper Truck Tractor 170,422 km          <NA>        13227   <NA>                <NA> Cummins ISX15  (600 hp)           4,925 Meritor FL941      (20,000 lb)  Meritor RZ-166    (69,000 lb)  Kenworth AG690 (69,000lb) Air     <NA>     259''        <NA> 18 speed main &     4 speed au            <NA> 7,750
## 5     New     Peterbilt       367 T/A Wet-Kit Tractor c/w 58'' Sleeper   3,367 km          <NA>        12180   <NA>                <NA>  Cummins ISX15  (550hp)              38 Dana Spicer E14621  (14,600 lb Dana D46-170     (46,000lb) ta Peterbilt Air-Trak  (46,000lb)     <NA>     244''        <NA>  RTLO18918B  Fuller (18 speed)            <NA> 3,300
## 6     New     Peterbilt       367 T/A Wet-Kit Tractor c/w 58'' Sleeper   3,421 km          <NA>        12179   <NA>                <NA>  Cummins ISX15  (550hp)              46 Dana Spicer E14621  (14,600 lb Dana D46-170     (46,000lb) ta Peterbilt Air-Trak  (46,000lb)     <NA>     244''        <NA>  RTLO18918B  Fuller (18 speed)            <NA> 3,300
## 7     New     Peterbilt       367 T/A Wet-Kit Tractor c/w 58'' Sleeper   2,157 km          <NA>        12181   <NA>                <NA>  Cummins ISX15  (550hp)              64 Dana Spicer E14621  (14,600 lb Dana D46-170     (46,000lb) ta Peterbilt Air-Trak  (46,000lb)     <NA>     244''        <NA>  RTLO18918B  Fuller (18 speed)            <NA> 9,880
## 8     New     Peterbilt       367 T/A Wet-Kit Tractor c/w 58'' Sleeper   3,444 km          <NA>        12954   <NA>                <NA>  Cummins ISX15  (550hp)              45 Dana Spicer E14621  (14,600 lb Dana D46-170     (46,000lb) ta Peterbilt Air-Trak  (46,000lb)     <NA>     244''        <NA>  RTLO18918B  Fuller (18 speed)            <NA> 9,880
## 9     New     Peterbilt       367 T/A Wet-Kit Tractor c/w 58'' Sleeper   3,427 km          <NA>        12955   <NA>                <NA>  Cummins ISX15  (550hp)              43 Dana Spicer E14621  (14,600 lb Dana D46-170     (46,000lb) ta Peterbilt Air-Trak  (46,000lb)     <NA>     244''        <NA>  RTLO18918B  Fuller (18 speed)            <NA> 9,880
## 10    New     Peterbilt       367 T/A Wet-Kit Tractor c/w 58'' Sleeper   3,982 km          <NA>        12182   <NA>                <NA>  Cummins ISX15  (550hp)              78 Dana Spicer E14621  (14,600 lb Dana D46-170     (46,000lb) ta Peterbilt Air-Trak  (46,000lb)     <NA>     244''        <NA>  RTLO18918B  Fuller (18 speed)            <NA> 9,880
## 11    New     Peterbilt       367 T/A Wet-Kit Tractor c/w 58'' Sleeper  23,293 km          <NA>        12953   <NA>                <NA>  Cummins ISX15  (550hp)             394 Dana Spicer E14621  (14,600 lb Dana D46-170     (46,000lb) ta Peterbilt Air-Trak  (46,000lb)     <NA>     244''        <NA>  RTLO18918B  Fuller (18 speed)            <NA> 9,880
## 12    New     Peterbilt       367 T/A Wet-Kit Tractor c/w 58'' Sleeper  27,215 km          <NA>        12509   <NA>                <NA>  Cummins ISX15  (550hp)             458 Dana Spicer E14621  (14,600 lb Dana D46-170     (46,000lb) ta Peterbilt Air-Trak  (46,000lb)     <NA>     244''        <NA>  RTLO18918B  Fuller (18 speed)            <NA> 6,600
## 13   Used         Volvo                                 VNL64T 780-730  72,000 km VNL64T780-730         <NA>   <NA>                <NA>                    <NA>            <NA>                           <NA>                           <NA>                           <NA>     <NA>      <NA>        <NA>                           <NA>            <NA> 5,000
## 14    New     Peterbilt 367 T/A Wet Kit Tractor c/w       58'' Sleeper  60,657 km          <NA>        10838   <NA>                <NA>  Cummins ISX15  (550hp)           1,822 Dana Spicer E14621  (14,600 lb Dana D46-170HP (46,000lb) tand Peterbilt Air-Trak  (46,000lb)     <NA>     244''        <NA>  RTLO18918B  Fuller (18 speed)            <NA> 1,800
## 15   Used International                                   ProStar +122  36,236 km          <NA>       463555    Air               White             Cummins ISX            <NA>         Arvin Meritor 13200 lb         Arvin Meritor 40000 lb                     Int'l IROS  11R22.5    228 in         450      Eaton Fuller D/O (18 spd)           White 8,750
## 16   Used International                                   ProStar +122  33,000 km          <NA>       463543    Air               White             Cummins ISX            <NA>         Arvin Meritor 13200 lb         Arvin Meritor 46000 lb                     Int'l IROS 11R/22.5    236 in         475      Eaton Fuller D/O (18 spd)           White 5,900

现在,我意识到完全从 "ascending-order assumption"(我们称之为)转移到 1/13 假设可能更可取,我们可以通过更改 lris 计算。这将使我们无需根据从 unique() 调用收到的订单重新排序 cns

下面我将对此进行演示,恢复为无后缀的变量名,这将很有用,稍后将看到:

## change lris calculation to depend directly on 1/13 assumption; don't bother reordering
cns <- unique(names(testlist));
lcis <- match(names(testlist),cns);
lris <- c(1L,cumsum(lcis[-1]==1L)+1L);
df <- as.data.frame(testlist[match(1:length(cns),lcis)],stringsAsFactors=F)[0,];
df[max(lris),] <- NA;
for (ci in 1:length(cns)) { m <- lcis==ci; df[lris[m],ci] <- do.call(c,testlist[m]); };
df;
##    Status          Make                                          Model Kilometres Stock.Number                  Engine Number.of.Hours                     Front.axle                      Rear.axle                     Suspension Wheelbase                   Transmission    Price    Style.Trim Brakes Mfg.Exterior.Colour    Tires Engine..HP. Exterior.Colour
## 1     New     Peterbilt                 367 Tri-Drive c/w 58'' Sleeper   3,360 km        12949 Cummins ISX15  (550 hp)              44  Dana Spicer D2000  (20,000lb) Dana T69-170    (wide track) t Peterbilt Air-Trak  (66,000lb)     267''  RTLO18918B  Fuller (18 speed) 7,770          <NA>   <NA>                <NA>     <NA>        <NA>            <NA>
## 2     New      Kenworth                               T800 T/A Tractor  82,230 km        10720   Cummins ISX15 (550hp)           2,712 Dana Spicer D2000  (20,000 lb) Dana D46-170HPW (46,000 lb) ta Neway ADZ252    (52,000lb) Air     244'' Fuller 18 spd main AT1202 2 sp 9,500          <NA>   <NA>                <NA>     <NA>        <NA>            <NA>
## 3     New      Kenworth            T800 Tandem Tractor w/ 38'' Sleeper  98,521 km        10722   Cummins ISX15 (550hp)           2,790 Dana Spicer D2000  (20,000 lb) Dana D46-170HPW (46,000 lb) ta Neway ADZ252    (52,000lb) Air     244'' Fuller 18 spd main AT1202 2 sp 9,500          <NA>   <NA>                <NA>     <NA>        <NA>            <NA>
## 4    Used      Kenworth           W900 Tri-Drive Sleeper Truck Tractor 170,422 km        13227 Cummins ISX15  (600 hp)           4,925 Meritor FL941      (20,000 lb)  Meritor RZ-166    (69,000 lb)  Kenworth AG690 (69,000lb) Air     259'' 18 speed main &     4 speed au 7,750          <NA>   <NA>                <NA>     <NA>        <NA>            <NA>
## 5     New     Peterbilt       367 T/A Wet-Kit Tractor c/w 58'' Sleeper   3,367 km        12180  Cummins ISX15  (550hp)              38 Dana Spicer E14621  (14,600 lb Dana D46-170     (46,000lb) ta Peterbilt Air-Trak  (46,000lb)     244''  RTLO18918B  Fuller (18 speed) 3,300          <NA>   <NA>                <NA>     <NA>        <NA>            <NA>
## 6     New     Peterbilt       367 T/A Wet-Kit Tractor c/w 58'' Sleeper   3,421 km        12179  Cummins ISX15  (550hp)              46 Dana Spicer E14621  (14,600 lb Dana D46-170     (46,000lb) ta Peterbilt Air-Trak  (46,000lb)     244''  RTLO18918B  Fuller (18 speed) 3,300          <NA>   <NA>                <NA>     <NA>        <NA>            <NA>
## 7     New     Peterbilt       367 T/A Wet-Kit Tractor c/w 58'' Sleeper   2,157 km        12181  Cummins ISX15  (550hp)              64 Dana Spicer E14621  (14,600 lb Dana D46-170     (46,000lb) ta Peterbilt Air-Trak  (46,000lb)     244''  RTLO18918B  Fuller (18 speed) 9,880          <NA>   <NA>                <NA>     <NA>        <NA>            <NA>
## 8     New     Peterbilt       367 T/A Wet-Kit Tractor c/w 58'' Sleeper   3,444 km        12954  Cummins ISX15  (550hp)              45 Dana Spicer E14621  (14,600 lb Dana D46-170     (46,000lb) ta Peterbilt Air-Trak  (46,000lb)     244''  RTLO18918B  Fuller (18 speed) 9,880          <NA>   <NA>                <NA>     <NA>        <NA>            <NA>
## 9     New     Peterbilt       367 T/A Wet-Kit Tractor c/w 58'' Sleeper   3,427 km        12955  Cummins ISX15  (550hp)              43 Dana Spicer E14621  (14,600 lb Dana D46-170     (46,000lb) ta Peterbilt Air-Trak  (46,000lb)     244''  RTLO18918B  Fuller (18 speed) 9,880          <NA>   <NA>                <NA>     <NA>        <NA>            <NA>
## 10    New     Peterbilt       367 T/A Wet-Kit Tractor c/w 58'' Sleeper   3,982 km        12182  Cummins ISX15  (550hp)              78 Dana Spicer E14621  (14,600 lb Dana D46-170     (46,000lb) ta Peterbilt Air-Trak  (46,000lb)     244''  RTLO18918B  Fuller (18 speed) 9,880          <NA>   <NA>                <NA>     <NA>        <NA>            <NA>
## 11    New     Peterbilt       367 T/A Wet-Kit Tractor c/w 58'' Sleeper  23,293 km        12953  Cummins ISX15  (550hp)             394 Dana Spicer E14621  (14,600 lb Dana D46-170     (46,000lb) ta Peterbilt Air-Trak  (46,000lb)     244''  RTLO18918B  Fuller (18 speed) 9,880          <NA>   <NA>                <NA>     <NA>        <NA>            <NA>
## 12    New     Peterbilt       367 T/A Wet-Kit Tractor c/w 58'' Sleeper  27,215 km        12509  Cummins ISX15  (550hp)             458 Dana Spicer E14621  (14,600 lb Dana D46-170     (46,000lb) ta Peterbilt Air-Trak  (46,000lb)     244''  RTLO18918B  Fuller (18 speed) 6,600          <NA>   <NA>                <NA>     <NA>        <NA>            <NA>
## 13   Used         Volvo                                 VNL64T 780-730  72,000 km         <NA>                    <NA>            <NA>                           <NA>                           <NA>                           <NA>      <NA>                           <NA> 5,000 VNL64T780-730   <NA>                <NA>     <NA>        <NA>            <NA>
## 14    New     Peterbilt 367 T/A Wet Kit Tractor c/w       58'' Sleeper  60,657 km        10838  Cummins ISX15  (550hp)           1,822 Dana Spicer E14621  (14,600 lb Dana D46-170HP (46,000lb) tand Peterbilt Air-Trak  (46,000lb)     244''  RTLO18918B  Fuller (18 speed) 1,800          <NA>   <NA>                <NA>     <NA>        <NA>            <NA>
## 15   Used International                                   ProStar +122  36,236 km       463555             Cummins ISX            <NA>         Arvin Meritor 13200 lb         Arvin Meritor 40000 lb                     Int'l IROS    228 in      Eaton Fuller D/O (18 spd) 8,750          <NA>    Air               White  11R22.5         450           White
## 16   Used International                                   ProStar +122  33,000 km       463543             Cummins ISX            <NA>         Arvin Meritor 13200 lb         Arvin Meritor 46000 lb                     Int'l IROS    236 in      Eaton Fuller D/O (18 spd) 5,900          <NA>    Air               White 11R/22.5         475           White

可以看到,df的列顺序和df2不一样,但是可以证明数据是一致的:

## prove df2 and df are identical, ignoring the column order difference
identical(df,df2[names(df)]);
## [1] TRUE

我能想到的最佳解决方案

library(data.table)
listnames <- names(testlist) 
# "Color" "HP"    "Type"  "HP"    "Type"  "Color" "HP"    "Type" 

unames <- unique(listnames)
# "Color" "HP"    "Type"

a <- setNames(1:length(unames), unames)
# Color    HP  Type 
# 1     2     3 

d <- unname(a[listnames])
# [1] 1 2 3 2 3 1 2 3

splitted_list <- split(testlist, cumsum(shift(d, fill=0)>d))
# results in testlist splitted by increasing sequences in d
# (1,2,3), (2,3), (1, 2, 3)
# You can impose a different splitting condition here, for instance, 
# if each entry begins with 1, then cumsum(d==1) is adequate 

# and the last step is pretty much self explanatory
rbindlist(lapply(splitted_list, data.frame), fill=TRUE) 
#    Color  HP  Type
# 1:  Blue 405 Truck
# 2:    NA 400   Car
# 3: White 500 Truck

希望它能解决您的问题。

当从 Dropbox 应用拆分条件 cumsum(d==1) 的测试数据时,结果是

structure(list(Status = structure(c(1L, 1L, 1L, 2L, 1L, 1L, 1L, 
1L, 1L, 1L, 1L, 1L, 2L, 1L, 2L, 2L), .Label = c("New", "Used"
), class = "factor"), Make = structure(c(1L, 2L, 2L, 2L, 1L, 
1L, 1L, 1L, 1L, 1L, 1L, 1L, 3L, 1L, 4L, 4L), .Label = c("Peterbilt", 
"Kenworth", "Volvo", "International"), class = "factor"), Model = structure(c(1L, 
2L, 3L, 4L, 5L, 5L, 5L, 5L, 5L, 5L, 5L, 5L, 6L, 7L, 8L, 8L), .Label = c("367 Tri-Drive c/w 58'' Sleeper", 
"T800 T/A Tractor", "T800 Tandem Tractor w/ 38'' Sleeper", "W900 Tri-Drive Sleeper Truck Tractor", 
"367 T/A Wet-Kit Tractor c/w 58'' Sleeper", "VNL64T 780-730", 
"367 T/A Wet Kit Tractor c/w       58'' Sleeper", "ProStar +122"
), class = "factor"), Kilometres = structure(1:16, .Label = c("3,360 km", 
"82,230 km", "98,521 km", "170,422 km", "3,367 km", "3,421 km", 
"2,157 km", "3,444 km", "3,427 km", "3,982 km", "23,293 km", 
"27,215 km", "72,000 km", "60,657 km", "36,236 km", "33,000 km"
), class = "factor"), Stock.Number = structure(c(1L, 2L, 3L, 
4L, 5L, 6L, 7L, 8L, 9L, 10L, 11L, 12L, NA, 13L, 14L, 15L), .Label = c("12949", 
"10720", "10722", "13227", "12180", "12179", "12181", "12954", 
"12955", "12182", "12953", "12509", "10838", "463555", "463543"
), class = "factor"), Engine = structure(c(1L, 2L, 2L, 3L, 4L, 
4L, 4L, 4L, 4L, 4L, 4L, 4L, NA, 4L, 5L, 5L), .Label = c("Cummins ISX15  (550 hp)", 
"Cummins ISX15 (550hp)", "Cummins ISX15  (600 hp)", "Cummins ISX15  (550hp)", 
"Cummins ISX"), class = "factor"), Number.of.Hours = structure(c(1L, 
2L, 3L, 4L, 5L, 6L, 7L, 8L, 9L, 10L, 11L, 12L, NA, 13L, NA, NA
), .Label = c("44", "2,712", "2,790", "4,925", "38", "46", "64", 
"45", "43", "78", "394", "458", "1,822"), class = "factor"), 
    Front.axle = structure(c(1L, 2L, 2L, 3L, 4L, 4L, 4L, 4L, 
    4L, 4L, 4L, 4L, NA, 4L, 5L, 5L), .Label = c("Dana Spicer D2000  (20,000lb)", 
    "Dana Spicer D2000  (20,000 lb)", "Meritor FL941      (20,000 lb)", 
    "Dana Spicer E14621  (14,600 lb", "Arvin Meritor 13200 lb"
    ), class = "factor"), Rear.axle = structure(c(1L, 2L, 2L, 
    3L, 4L, 4L, 4L, 4L, 4L, 4L, 4L, 4L, NA, 5L, 6L, 7L), .Label = c("Dana T69-170    (wide track) t", 
    "Dana D46-170HPW (46,000 lb) ta", "Meritor RZ-166    (69,000 lb)", 
    "Dana D46-170     (46,000lb) ta", "Dana D46-170HP (46,000lb) tand", 
    "Arvin Meritor 40000 lb", "Arvin Meritor 46000 lb"), class = "factor"), 
    Suspension = structure(c(1L, 2L, 2L, 3L, 4L, 4L, 4L, 4L, 
    4L, 4L, 4L, 4L, NA, 4L, 5L, 5L), .Label = c("Peterbilt Air-Trak  (66,000lb)", 
    "Neway ADZ252    (52,000lb) Air", "Kenworth AG690 (69,000lb) Air", 
    "Peterbilt Air-Trak  (46,000lb)", "Int'l IROS"), class = "factor"), 
    Wheelbase = structure(c(1L, 2L, 2L, 3L, 2L, 2L, 2L, 2L, 2L, 
    2L, 2L, 2L, NA, 2L, 4L, 5L), .Label = c("267''", "244''", 
    "259''", "228 in", "236 in"), class = "factor"), Transmission = structure(c(1L, 
    2L, 2L, 3L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, NA, 1L, 4L, 4L
    ), .Label = c("RTLO18918B  Fuller (18 speed)", "Fuller 18 spd main AT1202 2 sp", 
    "18 speed main &     4 speed au", "Eaton Fuller D/O (18 spd)"
    ), class = "factor"), Price = structure(c(1L, 2L, 2L, 3L, 
    4L, 4L, 5L, 5L, 5L, 5L, 5L, 6L, 7L, 8L, 9L, 10L), .Label = c("7,770", 
    "9,500", "7,750", "3,300", "9,880", "6,600", 
    "5,000", "1,800", "8,750", "5,900"), class = "factor"), 
    Style.Trim = structure(c(NA, NA, NA, NA, NA, NA, NA, NA, 
    NA, NA, NA, NA, 1L, NA, NA, NA), .Label = "VNL64T780-730", class = "factor"), 
    Brakes = structure(c(NA, NA, NA, NA, NA, NA, NA, NA, NA, 
    NA, NA, NA, NA, NA, 1L, 1L), .Label = "Air", class = "factor"), 
    Mfg.Exterior.Colour = structure(c(NA, NA, NA, NA, NA, NA, 
    NA, NA, NA, NA, NA, NA, NA, NA, 1L, 1L), .Label = "White", class = "factor"), 
    Tires = structure(c(NA, NA, NA, NA, NA, NA, NA, NA, NA, NA, 
    NA, NA, NA, NA, 1L, 2L), .Label = c("11R22.5", "11R/22.5"
    ), class = "factor"), Engine..HP. = structure(c(NA, NA, NA, 
    NA, NA, NA, NA, NA, NA, NA, NA, NA, NA, NA, 1L, 2L), .Label = c("450", 
    "475"), class = "factor"), Exterior.Colour = structure(c(NA, 
    NA, NA, NA, NA, NA, NA, NA, NA, NA, NA, NA, NA, NA, 1L, 1L
    ), .Label = "White", class = "factor")), .Names = c("Status", 
"Make", "Model", "Kilometres", "Stock.Number", "Engine", "Number.of.Hours", 
"Front.axle", "Rear.axle", "Suspension", "Wheelbase", "Transmission", 
"Price", "Style.Trim", "Brakes", "Mfg.Exterior.Colour", "Tires", 
"Engine..HP.", "Exterior.Colour"), row.names = c(NA, -16L), class = "data.frame")