麻烦大家帮我看一下下面的命令有问题吗?提示“unrecognized command: ( invalid command name”
twoway (scatter lnpatent lncharge) (lfit lnpatent lncharge)
(lfit lnpatent lncharge if id==1)
(lfit lnpatent lncharge if id==2)
(lfit lnpatent lncharge if id==3)
(lfit lnpatent lncharge if id==4)
(lfit lnpatent lncharge if id==5),
legend(off)