提取表达量最高的基因

Question

请问一下这个数据怎么提取最大的前10位，这个gain是数据，显示是numeric类型，但是order后出现的不知道是按什么排的，想要提取表达量最高的10个基因，不知道如何操作

 order(GAIN,decreasing = TRUE)
 [1] 38 55 37 25  2 54 10  9 57 35 20 42 36 18 61 34 17 16 19 39 58 59 60 67  1
[26] 26 27  7 40 32 23 28  5 43 24 53 15 21  3 12  8 22 13 52 66  4 11 31 62 49
[51] 41 56 29 33 30  6 46 48 47 63 45 64 44 14 65 51 50
> GAIN
   SLC2A1      MUC1      RRM2     LPIN1    SLC1A4      DPP4     HSPD1      MAP2 
 5.877034 15.280289  4.159132  3.707052  4.972875  2.531646  5.424955  3.887884 
     TP63      TFRC      IDUA    MAPK10   SLC7A11       PAM      EGR1     DUSP1 
11.844485 12.567812  3.707052  3.978300  3.797468  1.627486  4.339964  6.781193 
    VEGFA       MYB    MAP3K5      ESR1      CYCS       MET    HILPDA     KCNH2 
 6.871609  7.594937  6.781193  9.674503  4.339964  3.887884  5.063291  4.792043 
     MTDH     VLDLR      IL33       CA9     NTRK2       TXN      TLR4      CDK1 
15.370705  5.605787  5.515371  5.063291  2.893309  2.712477  3.707052  5.334539 
       TH       WT1    SLC3A2       BAD       CCS     CCND1     GAPDH      KRAS 
 2.893309  7.052441  9.945750  8.589512 17.992767 28.028933  6.781193  5.424955 
     NOS1      FLT3     CDKN3       FOS       NGB     ACTC1     CHAC1     DUOX2 
 3.526221  9.041591  4.882459  1.717902  1.989150  2.350814  2.169982  2.350814 
   SLC7A5    ACADVL   ALOX15B     BRCA1      MAPT      NGFR     BIRC5      PRNP 
 3.616637  1.446655  1.537071  3.797468  4.611212 13.471971 19.258590  3.435805 
    AURKA       CBS      CSTB     TRPM2     S100B      XBP1      MAOA      MAOB 
11.211573  6.509946  6.509946  6.509946  7.142857  3.707052  2.079566  1.898734 
     PGK1     AIFM1      G6PD 
 1.627486  3.797468  6.148282 
> class（GAIN)
Error: unexpected input in "class（"
> class(GAIN)
[1] "numeric"