[求助] 用LATEX软件画弧怎么画？

Originally posted by onesupeng at 2011-07-12 14:49:13:
\begin{picture}(80,160)
\textcolor{white}{\put(0,0){\vector(0,1){120}} \put(0,0){\vector(1,0){90}}
\put(90,0){x} \put(0,120){y}
\put(-90,80){\line(1,0){180}}\put(0,0){\line(-1,0){90}}\textcolor{ ...

Originally posted by saladin983 at 2011-07-05 16:08:39:
什么用的弧线？要什么样的效果？