R语言 改变重置dataframe索引index

例如：

将

                   MsgType/Cxr NoOfMsgs AvgElpsdTime(ms)
    161                   AM       86            30.13
    171                   CM        1              104
    18                    CO       27          1244.81
    19                    US       23          1369.61
    20                    VK        2              245
    21                    VS       11          1273.82
    112                  fqa       78          1752.22
    24                    SN       78          1752.22

变为

                 MsgType/Cxr NoOfMsgs AvgElpsdTime(ms)
    1                   AM        86            30.13
    2                   CM         1              104
    3                    CO       27          1244.81
    4                    US       23          1369.61
    5                    VK        2              245
    6                    VS       11          1273.82
    7                   fqa       78          1752.22
    8                    SN       78          1752.22

代码

rownames(dfr) <- 1:nrow(dfr)

转自
https://stackoverflow.com/questions/7567790/change-the-index-number-of-a-dataframe