Re: Epilog in ListLogPlot

*To*: mathgroup at smc.vnet.net*Subject*: [mg81500] Re: Epilog in ListLogPlot*From*: "D. Grady" <D.C.Grady at gmail.com>*Date*: Wed, 26 Sep 2007 06:37:15 -0400 (EDT)*References*: <fd58sd$2i1$1@smc.vnet.net>

The coordinates displayed on the axis of any kind of Log plot apparently don't correspond to the actual coordinate system used in the graphic. If you take a look at the Options of one of the graphics you generated, the tick marks show that the actual graphics coordinates run across the logarithms of the y values of your data points, although the labels on the y-axis don't reflect this. Two possible workarounds are to use Scaled coordinates, e.g. ListLogPlot[X, Epilog -> {Red, Point@Scaled@{.2, .3}}] or to do something like this: ListLogPlot[X, Epilog -> {Red, Point@{7, Log[7] }} ] Hope that helps! -Daniel Grady On Sep 23, 3:41 am, Bruce Colletti <vze26... at verizon.net> wrote: > Re 6.0.1 under WinXP. > > Consider the code: > > X = {{2, 4}, {9, 5}, {12, 13}}; > ListPlot[X, Epilog -> {Red, Point@{4, 6}}] > ListLogPlot[X, Epilog -> {Red, Point@{7, 7}}] > > Helptext says ListLogPlot has ListPlot's options. > > Unlike Plot #1, why doesn't the red dot appear in Plot #2? > > Thankx. > > Bruce