马上注册,结交更多好友,享用更多功能,让你轻松玩转社区。
您需要 登录 才可以下载或查看,没有账号?我要加入
x
- % pic 1
- close all
- a=2;b=1.2;
- c=sqrt(a^2+b^2);
- C='black';
- y=-3:.1:3;
- xa=sqrt(1+y.^2/b^2)*a;
- xd=-sqrt(1+y.^2/b^2)*a;
- figure;
- plot(xa,y,'linewidth',2,'color',C);
- hold on;
- plot(xd,y,'linewidth',2,'color',C);
- ylim([-4,4]);
- plot([0,0],[-4,4],'linewidth',2,'color',C);
- fill([-0.15,0,0.15],[3.5,4,3.5],'k');
- plot([-6,6],[0,0],'linewidth',2,'color',C);
- fill([5.5,6,5.5],[0.12,0,-0.12],'k')
- xf=a^2/c;
- plot([xf,xf],[-3.2,3.2],'linewidth',2,...
- 'linestyle',':','color',C);
- plot(c,0,'.','color',C,'markersize',16);
- plot(-c,0,'.','color',C,'markersize',16);
- text(5.6,-0.5,'X','fontsize',14,'fontname','宋体');
- text(0.4,3.5,'Y','fontsize',14,'fontname','宋体');
- text(-0.3,-0.3,'O','fontsize',14,'fontname','宋体');
- text(c+0.1,-0.3,'F2','fontsize',14,'fontname','宋体');
- text(-c-0.3,-0.3,'F1','fontsize',14,'fontname','宋体');
- plot(3,sqrt(9/a^2-1)*b,'.','color',C,'markersize',18);
- plot(xf,1,'.','color',C,'markersize',18);
- x1=3;y1=sqrt(9/a^2-1)*b;x2=xf;y2=1;
- P=polyfit([x1,x2],[y1,y2],1);
- xt=xf:.1:5;
- yt=polyval(P,xt);
- plot(xt,yt,'linewidth',2,'color',C);
- text(3+0.1,sqrt(9/a^2-1)*b-0.2,'P','fontsize',14,...
- 'fontname','宋体');
- text(x2-0.5,y2,'P1','fontsize',14,'fontname','宋体');
- plot(xt(end),yt(end),'.','color',C,'markersize',18);
- text(xt(end)+0.2,yt(end),'A','fontsize',14,...
- 'fontname','宋体');
- plot([xf,xt(end)],[yt(end),yt(end)],':',...
- 'linewidth',2,'color',C);
- plot([c,x1],[0,y1],'linewidth',2,'color',C);
- text(-0.4,-4.5,'图1','fontsize',14,'fontname','宋体');
- axis off;set(gcf,'color','w');
复制代码
来自萝卜驿站
[ 本帖最后由 suffer 于 2006-10-9 21:09 编辑 ] |