当把一个factor转换成numeric时,数据会发生变化。
as.numeric(levels(f))[f]
# or
df$var <- as.numeric(levels(df$var))[df$var]
refer to How to convert a factor to an integer\numeric without a loss of information?
当把一个factor转换成numeric时,数据会发生变化。
as.numeric(levels(f))[f]
# or
df$var <- as.numeric(levels(df$var))[df$var]
refer to How to convert a factor to an integer\numeric without a loss of information?