Question

我有这个数据集：我想找到wt.Df和创始人相同的任何行的平均生存能力。然后我想替换数据集中的那些值

 Store;

 founder wt.Df Replicate Block Food_Source Viability
 1       A4  5905         1     1     Regular 0.9523810
 2       A4 24834         1     1     Regular 0.8095238
 3       A4 24834         2     1     Regular 0.8571429
 4       A4 27861         1     1     Regular 0.8095238
 5       A4 27861         2     1     Regular 0.9230769
 12      A3  5905         1     1     Regular 0.9473684
 13      A3 24834         1     1     Regular 0.9047619
 14      A3 27861         1     1     Regular 0.8571429

我知道这段代码会找到相似点之间的平均值，但我不知道如何替换数据集

tmp<- with(Store, mean(Viability[wt.Df == 27861 & founder == "A4"]))

通缉输出：

founder wt.Df Replicate Block Food_Source Viability
1       A4  5905         1     1     Regular 0.9523810
2       A4 24834         1     1     Regular 0.8333333
4       A4 27861         1     1     Regular 0.8663004
12      A3  5905         1     1     Regular 0.9473684
13      A3 24834         1     1     Regular 0.9047619
14      A3 27861         1     1     Regular 0.8571429

Answer 1

有一些很好的选择让人想到。首先，来自aggregate包的普通旧base：

aggregate( Viability ~ wt.Df + founder , FUN = mean , data = store )
#  wt.Df founder Viability
#1  5905      A3 0.9473684
#2 24834      A3 0.9047619
#3 27861      A3 0.8571429
#4  5905      A4 0.9523810
#5 24834      A4 0.8333333
#6 27861      A4 0.8663003

另一个好的选择是使用data.table包并通过分组变量进行聚合。我还为剩下的列记录每组的第一条记录，例如Block = Block[1]这就是你在结果中所拥有的......

require( data.table )
store <- data.table( store )
store[ , list( Viability = mean(Viability) , Block = Block[1], Replicate = Replicate[1] ) , by = list( wt.Df , founder ) ]
#   wt.Df founder Viability Block Replicate
#1:  5905      A4 0.9523810     1         1
#2: 24834      A4 0.8333333     1         1
#3: 27861      A4 0.8663003     1         1
#4:  5905      A3 0.9473684     1         1
#5: 24834      A3 0.9047619     1         1
#6: 27861      A3 0.8571429     1         1

Answer 2

我会尝试生成摘要数据集然后合并它们。

library(gdata)
library(plyr)

avg_summary <- ddply(Store, .(wt.DF, founder), summary, viability1 = mean(Viability))
Store <- join(Store, avg_summary)

# delete original Viability column
Store$Viability <- NULL
# rename viability1 -> Viability
Store <- rename.vars(Store, 'viability1', 'Viability')

找到均值并替换R中相同数据帧中的值

2 个答案: