Re: PolarPlot
- To: mathgroup at smc.vnet.net
- Subject: [mg87678] Re: PolarPlot
- From: Helen Read <hpr at together.net>
- Date: Tue, 15 Apr 2008 05:54:28 -0400 (EDT)
- References: <ftmu5p$50d$1@smc.vnet.net> <ftv938$80f$1@smc.vnet.net>
- Reply-to: HPR <read at math.uvm.edu>
dh wrote: > Hi Bruce, > > the radius in polar coordinates has to be real and positive. Therefore, Actually, no. In polar coordinates r is a *directed* distance, which may be positive or negative. > r=Sqrt[Cos[phi]] can not be the correct formula, we would get imaginary > > values. To prevent this, we may e.g. write: r=Sqrt[Abs[Cos[phi]] what > > gives the plot you are looking for. > > hope this helps, Daniel -- Helen Read University of Vermont