我的一直说xline无法识别  command xline is unrecognized
代码如下  有人知道么
twoway (scatter p_value beta)(kdensity beta, yaxis(2)),
xline(0.0138039, lc(black*0.5) lp(dash))
xline(0, lc(black*0.5) lp(solid))
yline(0.000,lc(black*0.5)lp(dash))
xlabel(-0.2(0.01)0.2)
xtitle("Estimator", size(*0.8)) xlabel(, format(%4.3f)labsize(small))
ytitle("Density",size(*0.8)) ylabel(, nogrid format(%4.3f) labsize(small))
ytitle("p value", size(*0.8) axis(2)) ylabel(, nogrid format(%4.3f) labsize(small) axis(2))
legend(r(1) order(1 "p value"2"Estimator"))
graphregion(fcolor(white)) ;