newbie PolarPlot question
- To: mathgroup at smc.vnet.net
- Subject: [mg25046] newbie PolarPlot question
- From: Doug Magnoli <dmagnoli at home.com>
- Date: Sun, 3 Sep 2000 22:11:05 -0400 (EDT)
- Sender: owner-wri-mathgroup at wolfram.com
I've defined:
r[t] := 16/(5 + 3 Cos[t])
Then I load Graphics, with:
<<Graphics`
and ask for:
PolarPlot[r, {t, 0, 2 Pi}], which tells me:
ParametricPlot::pptr:
{r Cos[t], r Sin[t]} does not evaluate to a pair
of real numbers at t = 2.617993877991494`*^-7
ParametricPlot::pptr:
{r Cos[t], r Sin[t]} does not evaluate to a pair
of real numbers at t = 0.25488992540742256`.
ParametricPlot::pptr:
{r Cos[t], r Sin[t]} does not evaluate to a pair
of real numbers at t = 0.5328694051959509`.
General::stop:
Further output of ParametricPlot ::pptr will be
suppressed during this calculation.
Near as I can make out, x and y should both evaluate to real numbers for
any value of theta between 0 and 2 Pi, so I don't know what I'm doing
wrong.
....and, BTW, how do you get all those quotes from mathematica pages into
this newsgroup without having to edit? I tried to copy, e.g.,
In[32]:= PolarPlot[4, {t, 0, 2 Pi}]
and I don't get the In[32]:= part. Also, when copying those error
messages, I had to edit extensively, or else they look like this when
copied / pasted:
ParametricPlot::"pptr": "\!\({\(\(r\\ \(\(Cos[t]\)\)\)\), \(\(r\\ \
\(\(Sin[t]\)\)\)\)}\) does not evaluate to a pair of real numbers at
\!\(t\) \
= \!\(2.617993877991494`*^-7\)."
tia,
-Doug Magnoli