我正在尝试使用fread函数将基因组比对结果读入R中的data.table对象。以下是比对结果文件的快照:
USI-EAS28:1:100:1786:674#0/1 + 1_maternal 68326824 CTCAATTATACTGAAAGAAACACAATATATCATA IIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIII 0
USI-EAS28:1:100:1786:940#0/1 + 16_maternal 11407541 CTATTAGTGACCTGCTGTGGGACCTTGGGATGGT IIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIII 0
USI-EAS28:1:100:1786:705#0/1 + 1_maternal 63849584 CTGAGGGTTTGTGTCAGGAAGGGGTGTGGAATTG IIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIII 0 0:T>C
USI-EAS28:1:100:1786:1168#0/1 - 5_maternal 31381649 GCATCATTCATGAAACAATTTTCAAGAGAGGAAA IIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIII 0
USI-EAS28:1:100:1787:582#0/1 + 10_maternal 54587781 CTACAATAATAATAGGGGACTAAAACACCCCACT IIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIII 0
USI-EAS28:1:100:1787:62#0/1 + 10_maternal 70390747 CTATTTGCTACTGAATTGTTAATTTTAAAACAGT IIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIII 0
USI-EAS28:1:100:1788:573#0/1 - 7_maternal 92583837 CACTGTCAACATTAGACAGACCAATGAGACAAAG IIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIII 0
USI-EAS28:1:100:1788:854#0/1 + 7_maternal 129611206 GTTTGTTTTTTTTTTTGAGATGGAGTCTCATTTT IIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIII 0 32:C>T
USI-EAS28:1:100:1788:185#0/1 - 13_maternal 23694307 CAAACAAACTCAAAATGGACTATCGACTGAAAAA IIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIII 0
USI-EAS28:1:100:1788:1339#0/1 - 13_maternal 33699510 TTAACTCTAGTTTTTAGGGATTGCAAATTAGACG IIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIII 0 0:A>G
第二列报告了读取对齐到的链 (+
表示正向,-
表示反向)。不幸的是,fread 试图将此列读入整数,并始终将该值分配为0。应该将此列读取为字符,甚至是布尔值。尝试使用参数 sep
和 sep2
并没有帮助。
colClasses
。如果在+
或-
后面没有数字,它现在会将其读取为character
。可以从R-Forge repo获取,通常几个小时内就可以获得(当它显示 rev 849 和状态:current 时)。 - Matt Dowle