r - 将一列包含确切信息的列拆分为两列

Question

我的数据看起来像这样:

    SNP Geno Allele
marker1   G1    AA
marker2   G1    TT
marker3   G1    TT
marker1   G2    CC
marker2   G2    AA
marker3   G2    TT
marker1   G3    GG
marker2   G3    AA
marker3   G3    TT

我希望它看起来像这样:

    SNP Geno Allele1 Allele2
marker1   G1       A       A
marker2   G1       T       T
marker3   G1       T       T
marker1   G2       C       C
marker2   G2       A       A
marker3   G2       T       T
marker1   G3       G       G
marker2   G3       A       A
marker3   G3       T       T

我正在使用这个:

strsplit(Allele, split extended = TRUE)

但这是行不通的。我是否需要其他命令？

Answer 1

从头到尾的另一种方法:

制作可复制的数据:

dat <- read.table(header = TRUE,  text = "SNP Geno    Allele
marker1 G1  AA
marker2 G1  TT
marker3 G1  TT
marker1 G2  CC
marker2 G2  AA
marker3 G2  TT
marker1 G3  GG
marker2 G3  AA
marker3 G3  TT")

更新后的提取“等位基因”列，将其拆分为单个字符，然后将这些字符分成数据框的两列:

EITHER

dat1 <- data.frame(t(matrix(
                     unlist(strsplit(as.vector(dat$Allele), split = "")), 
                     ncol = length(dat$Allele), nrow = 2)))

@joran的建议后， 或

dat1 <- data.frame(do.call(rbind, strsplit(as.vector(dat$Allele), split = "")))

THEN

将列名称添加到新列:

names(dat1) <- c("Allele1", "Allele2")

将两个新列附加到原始数据表中的列，如@ user1317221所示:

dat3 <- cbind(dat$SNP, dat$Geno, dat1)
        dat$SNP dat$Geno Allele1 Allele2
1 marker1       G1       A       A
2 marker2       G1       T       T
3 marker3       G1       T       T
4 marker1       G2       C       C
5 marker2       G2       A       A
6 marker3       G2       T       T
7 marker1       G3       G       G
8 marker2       G3       A       A
9 marker3       G3       T       T