行数发生改变，请删除缺失值。

谢谢您
请问用哪个命令删除缺失值

rq(formula, tau=.5, data, subset, weights, na.action,
   method="br", model = TRUE, contrasts, ...)
Argument中设置na.action
na.action       
a function to filter missing data. This is applied to the model.frame after any subset argument has been used. The default (with na.fail) is to create an error if any missing values are found. A possible alternative is na.omit, which deletes observations that contain one or more missing values.

lm1<-lm(ln_n2o ~ soil_moisture+nh4+no3+soil_temp+doc, flux, na.action="na.omit")
step(lm1)
还是出现上述问题，老师您指的Argument中设置na.action，应该怎么写代码
后来用多重插补把数据补全，就没再出现这问题了