r - 合并(平均)具有部分匹配标题名称的列

Question

我有一个看起来像的数据:

   AAA_1   AAA_2  AAA_3  BBB_1  BBB_2  BBB_3 CCC
1   1       1      1       2     2      2     1
2   3       1      4       0     0      0     0
3   5       3      0       1     1      1     1

对于每一行，我想为那些具有共同特征的列求平均值，如下所示

feature <- c("AAA","BBB","CCC")

所需的输出应如下所示:

   AAA   BBB   CCC
1   1       2   1
2   2.6     0   0
3   2.6     1   1

对于每个模式，我都能够做到:

data <- read.table("data.txt",header=T,row.name=1)
AAA <- as.matrix(rowMeans(data[ , grepl("AAA" , names( data ) ) ])

但我不知道如何对一行中的不同模式进行部分匹配

还尝试了其他一些事情，例如:

for (i in 1:length(features)){
feature[i] <- as.matrix(rowMeans(data[ , grepl(feature[i] , names( data ) ) ]))
}

Answer 1

假设您的 colnames始终如您的示例所示结构化，然后您可以拆分名称和聚合。

new_names <-  unlist(strsplit(names(df),"\\_.*"))
colnames(df) <- new_names
#Testing with your data, we need to prevent the loss of dimension by using drop = FALSE  
sapply(unique(new_names), function(i) rowMeans(df[, new_names==i, drop = FALSE]))
#          AAA BBB CCC
#[1,] 1.000000   2   1
#[2,] 2.666667   0   0
#[3,] 2.666667   1   1

数据:

df <- structure(list(AAA_1 = c(1L, 3L, 5L), AAA_2 = c(1L, 1L, 3L), 
AAA_3 = c(1L, 4L, 0L), BBB_1 = c(2L, 0L, 1L), BBB_2 = c(2L, 
0L, 1L), BBB_3 = c(2L, 0L, 1L), CCC = c(1L, 0L, 1L)), .Names = c("AAA_1", 
"AAA_2", "AAA_3", "BBB_1", "BBB_2", "BBB_3", "CCC"), class = "data.frame", row.names = c(NA, 
-3L))