根据每个组的另一个查找 table 有条件地为一个数据帧插入值?

Conditionally interpolate values for one data frame based on another lookup table per group?

这类似于下面的 。不过,我还需要再做几步:

• 按列分组 IDorder

• 对于df_dat中的每个val,在df_lookup table中查找相应的ratio,条件如下:

o   If val < min(df_lookup$val), set new_ratio = min(df_lookup$ratio)

o   If val > max(df_lookup$val), set new_ratio = max(df_lookup$ratio)

o   If val falls within df_lookup$val range, do a simple linear interpolation

我的数据:

library(dplyr)

df_lookup <- tribble(
  ~ID, ~order, ~pct, ~val, ~ratio,
  "batch1", 1, 1,  1, 0.2,
  "batch1", 1, 10, 8, 0.5,
  "batch1", 1, 25, 25, 1.2,
  "batch2", 2, 1, 2, 0.1,
  "batch2", 2, 10, 15, 0.75,
  "batch2", 2, 25, 33, 1.5,
  "batch2", 2, 50, 55, 3.2,
)
df_lookup
#> # A tibble: 7 x 5
#>   ID     order   pct   val ratio
#>   <chr>  <dbl> <dbl> <dbl> <dbl>
#> 1 batch1     1     1     1  0.2 
#> 2 batch1     1    10     8  0.5 
#> 3 batch1     1    25    25  1.2 
#> 4 batch2     2     1     2  0.1 
#> 5 batch2     2    10    15  0.75
#> 6 batch2     2    25    33  1.5 
#> 7 batch2     2    50    55  3.2


df_dat <- tribble(
  ~order, ~ID, ~val,
  1, "batch1", 0.1,
  1, "batch1", 30,
  1, "batch1", 2,
  1, "batch1", 12,
  2, "batch1", 45,
  2, "batch2", 1.5,
  2, "batch2", 30,
  2, "batch2", 13,
  2, "batch2", 60,
)
df_dat
#> # A tibble: 9 x 3
#>   order ID       val
#>   <dbl> <chr>  <dbl>
#> 1     1 batch1   0.1
#> 2     1 batch1  30  
#> 3     1 batch1   2  
#> 4     1 batch1  12  
#> 5     2 batch1  45  
#> 6     2 batch2   1.5
#> 7     2 batch2  30  
#> 8     2 batch2  13  
#> 9     2 batch2  60

之前的解决方案不尊重生成错误结果的分组。

示例:

对于 order = 2ID = batch1new_ratio 应该是 NA,因为这些条件不在查找 table 中。

对于 order = 1ID = batch2val = 30new_ratio 不应高于 1.2(最大 ratio 值)。

对于order = 1ID = batch1val = 2new_ratio = 0.243是0.2和0.5之间的插值ratio

感谢任何帮助!

#error
df_dat %>%
  group_by(ID, order) %>%
  mutate(new_ratio = with(df_lookup, approx(val, ratio, val))$y)
#> Error: Column `new_ratio` must be length 4 (the group size) or one, not 7

#wrong output
df_dat %>%
  group_by(ID, order) %>%
  mutate(val1 = val) %>%
  mutate(new_ratio = with(df_lookup, approx(val, ratio, val1))$y)
#> # A tibble: 9 x 5
#> # Groups:   ID, order [3]
#>   order ID       val  val1 new_ratio
#>   <dbl> <chr>  <dbl> <dbl>     <dbl>
#> 1     1 batch1   0.1   0.1    NA    
#> 2     1 batch1  30    30       1.39 
#> 3     1 batch1   2     2       0.1  
#> 4     1 batch1  12    12       0.643
#> 5     2 batch1  45    45       2.43 
#> 6     2 batch2   1.5   1.5     0.15 
#> 7     2 batch2  30    30       1.39 
#> 8     2 batch2  13    13       0.679
#> 9     2 batch2  60    60      NA

预期输出

# A tibble: 9 x 4
  order ID       val new_ratio
  <dbl> <chr>  <dbl>     <dbl>
1     1 batch1   0.1     0.2  
2     1 batch1  30       1.2  
3     1 batch1   2       0.243
4     1 batch1  12       0.643
5     2 batch1  45      NA    
6     2 batch2   1.5     0.1 
7     2 batch2  30       1.38 
8     2 batch2  13       0.65 
9     2 batch2  60       3.2  
library(dplyr)
df_dat %>% 
left_join(df_lookup, by=c('ID','order'), suffix = c(".dat", ".lkp")) %>% 
group_by(ID, order, val.dat) %>% 
mutate(ratio_new = case_when(val.dat < min(val.lkp) ~ min(ratio),
                             val.dat > max(val.lkp) ~ max(ratio),
                             #Add ifelse to handle the scenarios where val.lkp and ratio are NAs as approx will fail in these scenarios  
                             between(val.dat, min(val.lkp), max(val.lkp)) ~ ifelse(all(is.na(ratio)), NA_real_, approx(x=val.lkp, y=ratio, xout=val.dat)$y), 
                             TRUE ~ NA_real_)) %>% 
slice(1)

# A tibble: 9 x 7
# Groups:   ID, order, val.dat [9]
   order ID     val.dat   pct val.lkp ratio ratio_new
   <dbl> <chr>    <dbl> <dbl>   <dbl> <dbl>     <dbl>
1     1 batch1     0.1     1       1   0.2     0.2  
2     1 batch1     2       1       1   0.2     0.243
3     1 batch1    12       1       1   0.2     0.665
4     1 batch1    30       1       1   0.2     1.2  
5     2 batch1    45      NA      NA  NA      NA    
6     2 batch2     1.5     1       2   0.1     0.1  
7     2 batch2    13       1       2   0.1     0.65 
8     2 batch2    30       1       2   0.1     1.38 
9     2 batch2    60       1       2   0.1     3.2

data.table中使用rollrollends的选项:

df_lookup[, m := (ratio - shift(ratio, -1L)) / (val - shift(val, -1L))]

df_dat[, new_ratio := 
        df_lookup[.SD, on=.(order, ID, val), roll=Inf, rollends=c(FALSE, FALSE), 
            x.m * (i.val - x.val) + x.ratio]
    ]

#for val in df_dat that are more than those in df_lookup
df_dat[is.na(new_ratio), new_ratio := 
    df_lookup[copy(.SD), on=.(order, ID, val), roll=Inf, x.ratio]]

#for val in df_dat that are less than those in df_lookup
df_dat[is.na(new_ratio), new_ratio := 
        df_lookup[copy(.SD), on=.(order, ID, val), roll=-Inf, x.ratio]]

输出:

   order     ID  val new_ratio
1:     1 batch1  0.1 0.2000000
2:     1 batch1 30.0 1.2000000
3:     1 batch1  2.0 0.2428571
4:     1 batch1 12.0 0.6647059
5:     2 batch1 45.0        NA
6:     2 batch2  1.5 0.1000000
7:     2 batch2 30.0 1.3750000
8:     2 batch2 13.0 0.6500000
9:     2 batch2 60.0 3.2000000

数据:

library(data.table)
df_lookup <- fread('ID, order, pct, val, ratio
"batch1", 1, 1,  1, 0.2
"batch1", 1, 10, 8, 0.5
"batch1", 1, 25, 25, 1.2
"batch2", 2, 1, 2, 0.1
"batch2", 2, 10, 15, 0.75
"batch2", 2, 25, 33, 1.5
"batch2", 2, 50, 55, 3.2')

df_dat <- fread('order, ID, val
1, "batch1", 0.1
1, "batch1", 30
1, "batch1", 2
1, "batch1", 12
2, "batch1", 45
2, "batch2", 1.5
2, "batch2", 30
2, "batch2", 13
2, "batch2", 60')

最后两行代码也可以用非equi连接代替:

df_dat[is.na(new_ratio), new_ratio:= 
    df_lookup[copy(.SD), on=.(order, ID, val<val), x.ratio, mult="last"]]
df_dat[is.na(new_ratio), new_ratio:= 
    df_lookup[copy(.SD), on=.(order, ID, val>val), x.ratio, mult="first"]]
df_dat

这是我解决你的问题的方法,使用 data.table

我用了很多中间步骤,所以你可以检查结果和操作每个步骤,看看发生了什么/所以代码可以缩短很多。

library(data.table)

#set data to data.tables
setDT(df_dat); setDT(df_lookup)

#set range df_lookup values by ID and order combination
df_lookup[, `:=`( val2   = shift( val, type = "lead" ),
                  ratio2 = shift( ratio, type = "lead" ) ), 
          by = .( ID, order ) ][]

#join non-equi
df_dat[ df_lookup, 
        `:=`( val_start = i.val, 
              val_end = i.val2, 
              ratio_start = i.ratio, 
              ratio_end = i.ratio2 ), 
        on = .( ID, order, val > val, val < val2) ][]


#interpolatie new_ratio for values that fall within a range of dt_lookup
df_dat[, new_ratio := ratio_start + ( (val - val_start) * (ratio_end - ratio_start) / (val_end - val_start) )][]

#create data.table with ratio-value for minimum- and maximum value in df_lookup
df_lookup_min_max <- df_lookup[, .( val_min = min( val ), val_max = max( val ),
                                    ratio_min = min( ratio ), ratio_max = max( ratio ) ), 
                               by = .(ID, order) ]
df_lookup_min_max_melt <- melt( df_lookup_min_max, 
                                id.vars = c( "ID", "order" ),
                                measure.vars = patterns( val = "^val", 
                                                         ratio = "^ratio" ) )

df_dat[ is.na( new_ratio ), 
        new_ratio := df_lookup_min_max_melt[ df_dat[ is.na( new_ratio ), ],
                                             ratio, 
                                             on = .(ID, order, val ),
                                             roll = "nearest" ] ][]

df_dat[, `:=`(val_start = NULL, val_end = NULL, ratio_start = NULL, ratio_end = NULL)][]

最终输出

#    order     ID  val new_ratio
# 1:     1 batch1  0.1 0.2000000
# 2:     1 batch1 30.0 1.2000000
# 3:     1 batch1  2.0 0.2428571
# 4:     1 batch1 12.0 0.6647059
# 5:     2 batch1 45.0        NA
# 6:     2 batch2  1.5 0.1000000
# 7:     2 batch2 30.0 1.3750000
# 8:     2 batch2 13.0 0.6500000
# 9:     2 batch2 60.0 3.2000000

编辑

5: 2 batch1 45.0 NA 在这里是因为在您的 df_lookup...
中没有 order == 2 & ID == batch1 组合 也许这是一个错字?
尽管如此:代码似乎处理得很好 ;-)