Re: Asking PlotRange to take a Dynamic value

*To*: mathgroup at smc.vnet.net*Subject*: [mg98028] Re: Asking PlotRange to take a Dynamic value*From*: Andrew <dr.a.graham at googlemail.com>*Date*: Sat, 28 Mar 2009 05:43:17 -0500 (EST)*References*: <gqfl0o$kra$1@smc.vnet.net> <gqiab6$oq5$1@smc.vnet.net>

On Mar 27, 10:38 am, dh <d... at metrohm.com> wrote: > Hi Andrew, > > the whole Plot is dynamic, not simple the PlotRange. Therefore, put the > > "Dynamic" around Plot, not around "z": > > Manipulate[ > > Dynamic@Plot[{Log[x], x^0.2, x^0.25, x^0.3}, {x, 0.01, n}, > > PlotStyle -> {Red, Blue, Blue, Blue}, > > PlotRange -> {{1, z}, {0, 55}}], > > Style["Log[x] vs. \!\(\*SuperscriptBox[\"x\", \"a\"]\) for small \ > > positive a 0.2, 0.25 & 0.3", 12, Bold], > > Row[{Style["x", Bold], " from 1 to ", > > PopupMenu[Dynamic[z], {10, 500, 10000, 500000}]}], {n, 0.1, > > Dynamic[z], Appearance -> "Labeled"}] > > Allow me some criticism. I do not see the point of the manipulate, it > > simple hides part of the plot. Would it not make more sense, if you > > would "manipulate" e.g. the PlotRange and always draw the whole plot? > > Daniel > > Andrew wrote: > > Hello, > > > I apologise in advance for what is probably a stupid question, but I > > would appreciate some help in persuading PlotRange to take a Dynamic > > value - or suggesting another way to go about things entirely! > > > For teaching purposes I wanted to draw a series of graphs of Log[x] > > vs. x^a for small positive values of a at different scales (simply to > > illustrate how Log[x] is eventually < x^a, for any positive a). I > > thought I would use Manipulate to allow students to explore this > > interactively. > > > E.g for x=0 to 10: > > > Manipulate[ > > Plot[{Log[x], x^0.2, x^0.25, x^0.3}, {x, 0.001, n}, > > PlotStyle -> {Red, Blue, Blue, Blue}, > > PlotRange -> {{0, 10}, {0, 3}}], > > Style["Log[x] vs. \!\(\*SuperscriptBox[\"x\", \"a\"]\) for small \ > > positive a 0.2, 0.25 & 0.3", 12, Bold], > > Style["x = 0 to 10", 12, Bold], {n, 0.01, 10, > > Appearance -> "Labeled"}] > > > & for x=0 to 500,000: > > > Manipulate[ > > Plot[{Log[x], x^0.2, x^0.25, x^0.3}, {x, 0.001, n}, > > PlotStyle -> {Red, Blue, Blue, Blue}, > > PlotRange -> {{0, 500000}, {0, 55}}], > > Style["Log[x] vs. \!\(\*SuperscriptBox[\"x\", \"a\"]\) for small \ > > positive a 0.2, 0.25 & 0.3", 12, Bold], > > Style["x = 0 to 500,000", 12, Bold], {n, 0.01, 500000, > > Appearance -> "Labeled"}] > > > But rather than a series of separate graphs I thought it would be more > > elegant to combine them in one plot with a Dynamic value to choose the > > scale, e.g.: > > > Manipulate[ > > Plot[{Log[x], x^0.2, x^0.25, x^0.3}, {x, 0.01, n}, > > PlotStyle -> {Red, Blue, Blue, Blue}, > > PlotRange -> {{1, Dynamic[z]}, {0, 55}}], > > Style["Log[x] vs. \!\(\*SuperscriptBox[\"x\", \"a\"]\) for small \ > > positive a 0.2, 0.25 & 0.3", 12, Bold], > > Row[{Style["x", Bold], " from 1 to ", > > PopupMenu[Dynamic[z], {10, 500, 10000, 500000}]}], {n, 0.1, > > Dynamic[z], Appearance -> "Labeled"}] > > > Unfortunately, although the graphs will plot, with continually > > updating axes, what I really want is to change the plot range for each > > value of x & fix it so one can see the curves evolving more easily. I > > hope the 2 individual examples above make it clear what I hoped for - > > essentially, to click from one to the next with the PopupMenu. The > > error message reads (e.g. for x=10): > > > Plot::prng: Value of option PlotRange -> {{1,10},{0,55}} is not All, > > Full, Automatic, a positive machine number, or an appropriate list of > > range specifications. >> > > > What's gone wrong? PlotRange -> {{1,10},{0,55}} looks like "an > > appropriate list of range specifications" to me! > > > Any advice appreciated > > > Best regards > > > Andrew Graham Jens-Peer, Daniel - thank you! 1) I'm a fool - of course, PlotRange -> {{1, z}, {0, 55}}, not PlotRange -> {{1, Dynamic[z]}, {0, 55}} 2) Daniel, the aesthetic point is well taken Much appreciated Andrew