Re: newbie PolarPlot question

*To*: mathgroup at smc.vnet.net*Subject*: [mg25055] Re: newbie PolarPlot question*From*: quizzik at yahoo.com (Thomas Anderson)*Date*: Thu, 7 Sep 2000 22:27:59 -0400 (EDT)*Organization*: Stanford University*References*: <8ov0jn$9p8@smc.vnet.net>*Sender*: owner-wri-mathgroup at wolfram.com

>> I've defined: >> >> r[t] := 16/(5 + 3 Cos[t]) (when this is used in PolarPlot, error messages are generated) The problem here comes from an important bit of syntax that is missing from your definition. As stated above, 'r' is defined only for the symbol 't', not for a variable in general. What you want is: r[t_] := 16/(5 + 3 Cos[t]) The underscore indicates that 't_' is a *pattern* which stands for any value supplied as an argument to 'r'. Happy plotting! -Tom