基于3列组合并排除重复组合的R子集数据框

Question

我有一个看起来像这样的数据集:

Experiment  Sequence    Parameter   Time
Exp1    AAAA    2   10
Exp2    AAAA    2   11
Exp3    AAAA    2   12
Exp1    BBBB    2   13.1
Exp1    BBBB    3   13.2
Exp1    BBBB    4   13.3
Exp2    BBBB    2   14.1
Exp2    BBBB    3   14.2
Exp3    BBBB    2   16.3
Exp3    BBBB    3   16.4
Exp3    BBBB    4   16.5
Exp3    BBBB    5   16.6
Exp1    CCCC    2   20
Exp2    CCCC    2   22.2
Exp1    DDDD    3   22.3
Exp1    DDDD    2   22.4
Exp2    DDDD    3   25.2
Exp2    DDDD    2   25.3
Exp3    DDDD    3   27
Exp1    EEEE    2   28
Exp2    EEEE    3   29
Exp3    EEEE    4   30
Exp1    FFFF    2   33.2
Exp1    FFFF    3   33.4
Exp1    FFFF    4   33.6
Exp2    FFFF    2   35.1
Exp2    FFFF    3   35.2
Exp1    GGGG    2   40.1
Exp1    GGGG    2   40.2
Exp1    GGGG    2   40.3
Exp1    GGGG    2   42
Exp2    GGGG    2   42.3
Exp2    GGGG    2   44.3
Exp3    GGGG    2   45.3
Exp3    GGGG    2   45.4

真实数据集有:

• 许多实验
• 许多序列，可以出现在一个或多个实验中
• 每个Sequence可以有3-4个不同的参数

对于我的分析(当时)，我首先需要根据前 3 列的组合对数据帧进行子集化:实验、序列和参数。规则是:

• 序列+参数组合应该存在于数据框的所有实验中。如果不是，则应将其排除在外。在示例中:BBBB+4, BBBB+5, CCCC+2, ... 应该离开，BBBB+2, DDDD+3,... 可以留下
• 如果序列+参数组合在同一实验中多次出现，则也应排除这些组合。在示例中:GGGG+2

所以例子中的dataframe经过子集化后应该变成这样:

Experiment  Sequence    Parameter   Time
Exp1    AAAA    2   10
Exp2    AAAA    2   11
Exp3    AAAA    2   12

Exp1    BBBB    2   13.1
Exp2    BBBB    2   14.1
Exp3    BBBB    2   16.3

Exp1    BBBB    3   13.2
Exp2    BBBB    3   14.2
Exp3    BBBB    3   16.4

Exp1    DDDD    3   22.3
Exp2    DDDD    3   25.2
Exp3    DDDD    3   27

有人可以帮助我吗？谢谢!

Experiment <- c("Exp1", "Exp2", "Exp3", "Exp1", "Exp1", "Exp1", "Exp2", "Exp2", "Exp3", "Exp3", "Exp3", "Exp3", "Exp1", "Exp2", "Exp1", "Exp1", "Exp2", "Exp2", "Exp3", "Exp1", "Exp2", "Exp3", "Exp1", "Exp1", "Exp1", "Exp2", "Exp2", "Exp1", "Exp1", "Exp1",   "Exp1", "Exp2", "Exp2", "Exp3", "Exp3")
Sequence <- c("AAAA", "AAAA", "AAAA", "BBBB", "BBBB", "BBBB", "BBBB", "BBBB", "BBBB", "BBBB","BBBB", "BBBB", "CCCC", "CCCC", "DDDD", "DDDD", "DDDD", "DDDD", "DDDD", "EEEE", "EEEE", "EEEE", "FFFF", "FFFF", "FFFF", "FFFF", "FFFF", "GGGG", "GGGG", "GGGG", "GGGG", "GGGG", "GGGG", "GGGG", "GGGG")
Parameter <- c("2", "2", "2", "2", "3", "4", "2", "3", "2", "3", "4", "5", "2", "2", "3", "2", "3", "2", "3", "2", "3", "4", "2", "3", "4", "2", "3", "2", "2", "2", "2", "2", "2", "2", "2")
Time <- c(10.0, 11.0, 12.0, 13.1, 13.2, 13.3, 14.1, 14.2, 16.3, 16.4, 16.5, 16.6, 20.0, 22.2, 22.3, 22.4, 25.2, 25.3, 27.0, 28.0, 29.0, 30.0, 33.2, 33.4, 33.6, 35.1, 35.2, 40.1, 40.2, 40.3, 42.0, 42.3, 44.3, 45.3, 45.4)
df <- data.frame(Experiment, Sequence, Parameter, Time)

Answer 1

一个选项是data.table。我们将“data.frame”转换为“data.table”(setDT(df)，按“Sequence”、“Parameter”、if 的频率分组>unique 'Experiment' 中的元素是 3，我们对 Data.table (.SD) 进行子集化，然后，我们按 'Experiment'、'Sequence' 和 'Parameter' 分组，如果nrow 等于 1 (.N==1) 我们子集 Data.table (.SD)。

library(data.table)
setDT(df)[, if(uniqueN(Experiment)==3) .SD, by = .(Sequence, Parameter)
        ][,if(.N ==1) .SD , by = .(Experiment,Sequence, Parameter)]
#      Experiment Sequence Parameter Time
# 1:       Exp1     AAAA         2 10.0
# 2:       Exp2     AAAA         2 11.0
# 3:       Exp3     AAAA         2 12.0
# 4:       Exp1     BBBB         2 13.1
# 5:       Exp2     BBBB         2 14.1
# 6:       Exp3     BBBB         2 16.3
# 7:       Exp1     BBBB         3 13.2
# 8:       Exp2     BBBB         3 14.2
# 9:       Exp3     BBBB         3 16.4
#10:       Exp1     DDDD         3 22.3
#11:       Exp2     DDDD         3 25.2
#12:       Exp3     DDDD         3 27.0