如何提取R的strsplit()的结果

Question

关于问题 :

我有一个字符串向量foo:

>foo = c("1x2","3x4","5x6","7x8","9x10")

我将单个字符串拆分为"x"并将结果粘贴到goo中:

>goo = strsplit(foo, "x")
>goo
[[1]]
[1] "1" "2"

[[2]]
[1] "3" "4"

[[3]]
[1] "5" "6"

[[4]]
[1] "7" "8"

[[5]]
[1] "9"  "10"

如何从此列表中提取第一个和第二个"列"？(我想要(1,3,5,7,9)和(2,4,6,8,10))

Answer 1

用于sapply使用"[[")连续"提取":

 sapply(goo, "[[" , 1)
[1] "1" "3" "5" "7" "9"

我一直认为这应该是结果,但我可能不明白这些问题.