r - 在R中串联重复的数据框值

Question

我有一个很长的数据帧，其中将近56列中的1列具有许多不同的值，而其余数据根据第一列ID进行更改。这是一个例子

ID  chrom   left    right   ref_seq var_type    zygosity    transcript_name
0   chr1    1590327 1590328 a       SNP         Hom         NM_033486
0   chr1    1590327 1590328 a       SNP         Hom         NM_033487
0   chr1    1590327 1590328 a       SNP         Hom         NM_033488
0   chr1    1590327 1590328 a       SNP         Hom         NM_033489
0   chr1    1590327 1590328 a       SNP         Hom         NM_033492
0   chr1    1590327 1590328 a       SNP         Hom         NM_033493
1   chr1    1590526 1590527 g       SNP         Hom         NM_033486
1   chr1    1590526 1590527 g       SNP         Hom         NM_033487
1   chr1    1590526 1590527 g       SNP         Hom         NM_033488
1   chr1    1590526 1590527 g       SNP         Hom         NM_033489
1   chr1    1590526 1590527 g       SNP         Hom         NM_033492

理想的结果是将所有重复值连接到一个逗号分隔的字符串中，但仅维护一次ID，就像这样

ID  chrom   left    right   ref_seq var_type    zygosity    transcript_name
0   chr1    1590327 1590328 a       SNP         Hom         NM_033486NM_033487,NM_033488,NM_033489,NM_033492,NM_033493
1   chr1    1590526 1590527 g       SNP         Hom         NM_033486,NM_033487,NM_033488,NM_033489,NM_033492

我已经搜索了类似的问题，但the following solutions到目前为止还没有奏效。相反，他们返回了一个零行数据框。

Answer 1

data.table的一种方法：

library(data.table)
#setDT will convert the data.frame into data.table
#.SD gives you access to the groups of data.tables created by the 'by' argument
setDT(df)[, list(transcript_name = paste(transcript_name, collapse = ', ')), 
            by = c('ID', 'chrom', 'left', 'right', 'ref_seq', 'var_type', 'zygosity')]
#   ID chrom    left   right ref_seq var_type zygosity                                                  transcript_name
#1:  0  chr1 1590327 1590328       a      SNP      Hom NM_033486, NM_033487, NM_033488, NM_033489, NM_033492, NM_033493
#2:  1  chr1 1590526 1590527       g      SNP      Hom            NM_033486, NM_033487, NM_033488, NM_033489, NM_033492

数据

df <- read.table(header = TRUE, text = 'ID  chrom   left    right   ref_seq var_type    zygosity    transcript_name
0   chr1    1590327 1590328 a   SNP Hom NM_033486
                 0   chr1    1590327 1590328 a   SNP Hom NM_033487
                 0   chr1    1590327 1590328 a   SNP Hom NM_033488
                 0   chr1    1590327 1590328 a   SNP Hom NM_033489
                 0   chr1    1590327 1590328 a   SNP Hom NM_033492
                 0   chr1    1590327 1590328 a   SNP Hom NM_033493
                 1   chr1    1590526 1590527 g   SNP Hom NM_033486
                 1   chr1    1590526 1590527 g   SNP Hom NM_033487
                 1   chr1    1590526 1590527 g   SNP Hom NM_033488
                 1   chr1    1590526 1590527 g   SNP Hom NM_033489
                 1   chr1    1590526 1590527 g   SNP Hom NM_033492')