Re: y-axis direction

*To*: mathgroup at smc.vnet.net*Subject*: [mg116567] Re: y-axis direction*From*: Syd Geraghty <sydgeraghty at me.com>*Date*: Sun, 20 Feb 2011 05:25:04 -0500 (EST)

Hi, For those lucky enough to have David Park's Presentations Package: Needs["Presentations`Master`"] yticks = CustomTicks[-# + 50 &, {0, 50, 10, 5}]; Draw2D[{ListLineDraw[Table[{i, i^2}, {i, {1, 2, 3, 4, 5, 6}}]] /. DrawingTransform[#1 &, -#2 + 50 &]}, AspectRatio -> 0.63, Frame -> True, FrameTicks -> {{yticks, yticks // NoTickLabels}, {Automatic, Automatic}}, PlotRange -> {{0, 8}, {0, 50}}, PlotRangePadding -> {0.1, 1}, PlotLabel -> "Reverse y Axis Plot"] The thread is from 2009 I believe: [mg103510] How to plot with a reversed Y-axis? Cheers .... Syd Syd Geraghty B.Sc, M.Sc. sydgeraghty at mac.com Mathematica 8.0 for Mac OS X x86 (64-bit) (November 6, 2010) MacOS X V 10.6.5 Snow Leopard MacBook Pro 2.33 GHz Intel Core 2 Duo 2GB RAM On Feb 18, 2011, at 1:36 AM, telefunkenvf14 wrote: > On Feb 17, 4:18 am, "Rob Y. H. Chai" <yhc... at ucdavis.edu> wrote: >> Hi all, >> >> In the Plot command, the convention for y-axis is up for positive values. Is >> there an easy way to reverse the y-axis direction i.e. pointing down for >> increasing positive y values? Thanks. >> >> Rob Chai > > I have encountered the same problem... economists like to graph > inverse demand and supply equations (i.e., price(quantity)) rather > than the true relationship of quantity(price). > > Possible ways around this: > > (1) solving for the inverse relationship and then using Plot[] (one > could also use InverseFunction[] ---- not always straightforward as > your function may not be clearly invertible w/o providing assumptions > on parameters) > (2) using ContourPlot[], which incorporates the functionality of the > legacy function ImplicitPlot (you can still use ImplicitPlot; search > documentation for details) > > For the most part, I've settled on (1). > > -RG >