Re: Re: Needed Grid lines in Implicit Plot

*To*: mathgroup at smc.vnet.net*Subject*: [mg52828] Re: [mg52818] Re: [mg52648] Needed Grid lines in Implicit Plot*From*: Andrzej Kozlowski <akoz at mimuw.edu.pl>*Date*: Tue, 14 Dec 2004 05:59:22 -0500 (EST)*References*: <200412070909.EAA09155@smc.vnet.net> <200412130924.EAA23586@smc.vnet.net>*Sender*: owner-wri-mathgroup at wolfram.com

On 13 Dec 2004, at 18:24, Bob Walker wrote: > Remove ", {y, -4 , 4 }" iterator and it will work as you wish. > ImplicitPlot accepts only one iterator. You can inspect the > ImplicitPlot signature by: > ?ImplicitPlot > > I don't know why there is no error indication. > > Take care, > Bob Walker > > Narasimham wrote: > >> << Graphics`ImplicitPlot` >> ImplicitPlot[3 x + 5 y == 1, {x, -4 , 4}, {y, -4 , 4 }, >> GridLines ->{Range[-4, 4, 1], Range[-4, 4, 1]},AspectRatio -> >> Automatic]; >> >> This is quite simply false. There are two forms of Implicitplot. they are both described int he documentation (read till the end) ImplicitPlot[eqn, {x, a, b}] draws a graph of the set of points that satisfy \ the equation eqn. The variable x is associated with the horizontal axis and \ ranges from a to b. The remaining variable in the equation is associated \ with the vertical axis. ImplicitPlot[eqn, {x, a, x1, x2, ..., b}] allows the \ user to specify values of x where special care must be exercised. \ ImplicitPlot[{eqn1, eqn2, ...}, {x, a, b}] allows more than one equation to \ be plotted, with PlotStyles set as in the Plot function. ImplicitPlot[eqn, \ {x, a, b}, {y, a, b}] uses a contour plot method of generating the plot. \ This form does not allow specification of intermediate points The form of ImplicitPLot with one iterator only works on equations that can be "solved" algebraically using Solve. it produces a Graphics object, which is why it accepts the GridLines option. The other form of ImplicitPlot works much more generally, but it produces a CountourGraphics object, which needs to be converted to a Graphics object before using the GridLines option. Andrzej Kozlowski Chiba, Japan http://www.akikoz.net/~andrzej/ http://www.mimuw.edu.pl/~akoz/

**References**:**Needed Grid lines in Implicit Plot***From:*"Narasimham" <mathma18@hotmail.com>

**Re: Needed Grid lines in Implicit Plot***From:*Bob Walker <walkerbg@ieee.org>