> n<-10
> mycolors<-rainbow(n)
> pie(rep(1,n),labels=mycolors,col=mycolors)
> mycolors<-gray(0:n/n)
> pie(rep(1,n),labels=mygrays,col=mygrays)
Error in pie(rep(1, n), labels = mygrays, col = mygrays) :
  找不到对象'mygrays'