我正在尝试对一些大小约为2GB的文件进行fread操作,这些文件看起来像这样:
head file.bed
chr1 19922471 19924471 + NM_001204088 tss 1 0
chr1 19922471 19924471 + NM_001204088 tss 2 0
chr1 19922471 19924471 + NM_001204088 tss 3 0
chr1 19922471 19924471 + NM_001204088 tss 4 0
chr1 19922471 19924471 + NM_001204088 tss 5 0
chr1 19922471 19924471 + NM_001204088 tss 6 0
chr1 19922471 19924471 + NM_001204088 tss 7 0
chr1 19922471 19924471 + NM_001204088 tss 8 0
chr1 19922471 19924471 + NM_001204088 tss 9 0
chr1 19922471 19924471 + NM_001204088 tss 10 0
第四列也有相似数量的“-”。在R中读取时,“+/-”会变成0:
cov.data <- fread(file)
head(cov.data)
V1 V2 V3 V4 V5 V6 V7 V8
1: chr1 19922471 19924471 0 NM_001204088 tss 1 1
2: chr1 19922471 19924471 0 NM_001204088 tss 2 1
3: chr1 19922471 19924471 0 NM_001204088 tss 3 1
4: chr1 19922471 19924471 0 NM_001204088 tss 4 1
5: chr1 19922471 19924471 0 NM_001204088 tss 5 1
6: chr1 19922471 19924471 0 NM_001204088 tss 6 0
我查阅了文档,但是没能找出原因。有什么建议吗?由于fread仍在开发中,所以这可能是一个bug吗?