Re: How to draw an ellipse?
- To: mathgroup@smc.vnet.net
- Subject: [mg10393] Re: How to draw an ellipse?
- From: Allan Hayes <hay@haystack.demon.co.uk>
- Date: Mon, 12 Jan 1998 04:10:32 -0500
- References: <694b5p$kjs@smc.vnet.net>
Krishnan Jayakrishnan wrote: > Does any one know how to construct an ellipse? For example an ellipse > centered at (0,0) with intercepts at (-a,0,(a,0),(0,-b),(0,b) with > parametric equation > x(t) = a*cos(t) > y(t) = b*sin(t) > with t increasin from 0 to 2pi radians. -- In[2]:= x[t_] = a*Cos[t]; y[t_] = b*Sin[t]; In[3]:= a= 2; b = 1; In[4]:= ParametricPlot[{x[t],y[t]},{t,0,2Pi}, AspectRatio-> Automatic]; AspectRatio-> Automatic is needed to get the same scales in x and y directions. Instead of functions you can use formulas: In[5]:= Clear[x,y] In[6]:= {x,y} = {a Cos[t],b Sin[t]}; In[7]:= ParametricPlot[{x,y},{t,0,2Pi}, AspectRatio-> Automatic]; -- Allan Hayes Training and Consulting Leicester, UK hay@haystack.demon.co.uk http://www.haystack.demon.co.uk voice: +44 (0)116 271 4198 fax: +44 (0)116 271 8642