Re: How to draw several contours for one function, while

*To*: mathgroup at smc.vnet.net*Subject*: [mg127709] Re: How to draw several contours for one function, while*From*: analysismath <loveinla at gmail.com>*Date*: Thu, 16 Aug 2012 01:56:36 -0400 (EDT)*Delivered-to*: l-mathgroup@mail-archive0.wolfram.com*Delivered-to*: l-mathgroup@wolfram.com*Delivered-to*: mathgroup-newout@smc.vnet.net*Delivered-to*: mathgroup-newsend@smc.vnet.net*References*: <20120814082402.2D8BD6862@smc.vnet.net> <k0fjnc$qba$1@smc.vnet.net>

On Wednesday, August 15, 2012 3:39:24 AM UTC-4, Bob Hanlon wrote: > Without knowing the functions it is difficult to guess the best way to > > show what you might want to see. Manipulate may be a better way than > > Animate to examine what is going on. > > > > Manipulate[ > > pts = {x, y} /. > > Solve[{ > > f[x, y, a] == intersect, > > g[x, y, a] == 0}, > > {x, y}, Reals]; > > Show[ > > ContourPlot[f[x, y, a], > > {x, -8, 8}, {y, -8, 8}, > > Contours -> Range[0, 75, 15], > > ContourStyle -> Hue /@ (.7 Range[0, 1, 15/75] + .15), > > ContourShading -> None, > > ContourLabels -> All], > > ContourPlot[g[x, y, a] == 0, > > {x, -8, 8}, {y, -8, 8}, > > ContourShading -> None, > > ContourLabels -> All], > > Graphics[{Red, AbsolutePointSize[4], > > Tooltip[Point[#], #] & /@ pts}], > > PlotRange -> {{-8, 8}, {-7, 8}}], > > {{a, 0}, -5, 5, .5, Appearance -> "Labeled"}, > > {{intersect, 0}, 0, 75, 5, Appearance -> "Labeled"}, > > Initialization :> { > > f[x_, y_, a_] = (x - a/2)^2 + (y - a/4)^2 - 2, > > g[x_, y_, a_] = x + y - a}] > > > > > > Bob Hanlon > > > > > > On Tue, Aug 14, 2012 at 4:24 AM, <loveinla at gmail.com> wrote: > > > Dear all, > > > > > > Suppose I have two implicit functions, say, F(x, y) and G(x, y); both involve a parameter a. > > > > > > In one Animate, I need: > > > (1) several contours for function F(x, y) with its Max and Min values; > > > (2) only one contour for function G(x, y)==0. > > > (3) because I need to see how they change as parameter a changes, I want to use Animate to generate animation. > > > > > > Can anybody help? Thanks. > > > Thank you very much, Bob.

**References**:**How to draw several contours for one function, while only one contour***From:*loveinla@gmail.com