Basically I have dataframe with two columns (target_id and fpkm). I want to keep only those row names in first column that are not duplicated. For example in the below dataframe you can see there are two row names with the same name (almost) comp267138_c0_seq1 comp267138_c0_seq2 and from both and I want to keep only one comp267138_c0_seq2 based of high value in column 2. target_id fpkm comp247393_c0_seq1 3.197885 comp257058_c0_seq4 1.624577 comp242590_c0_seq1 1.750319 comp77911_c0_seq1 1.293059 comp241426_c0_seq1 1.626589 comp288413_c0_seq1 14.828853 comp294436_c0_seq1 11.555596 comp63603_c0_seq1 1.982386 comp267138_c0_seq1 8.594494 comp267138_c0_seq2 11.134958 comp321623_c0_seq1 6.934149