Thread Subject: stem not connected with the axis

hi,

I want to produce a figure showing the function -(x-3)^2-20
with a line joining the optimum point M(3,-20) with the
frame of the plot. How can I say MatLab this?

x=-50:50; plot(x,-(x-3).^2-20 ); stem(-3,-20); ??


Thank you

Thomas

Thomas Clerc:
<SNIP abusing <stem>...

> x=-50:50; plot(x,-(x-3).^2-20 ); stem(-3,-20); ??

should read:

     x=-50:50;
     plot(x,-(x-3).^2-20);
     yl=get(gca,'ylim');
     line([3;3],[yl(1);-20],'color',[1,0,0]);

us

"us " <us@neurol.unizh.ch> wrote in message
<f978s4$lo5$1@fred.mathworks.com>...
> Thomas Clerc:
> <SNIP abusing <stem>...
>
> > x=-50:50; plot(x,-(x-3).^2-20 ); stem(-3,-20); ??
>
> should read:
>
> x=-50:50;
> plot(x,-(x-3).^2-20);
> yl=get(gca,'ylim');
> line([3;3],[yl(1);-20],'color',[1,0,0]);
>
> us

us you are the best ever!!