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plotting - How does epilog position work in logplots?


I'm trying to use Epilog in my plots but the way that Epilog uses coordinate positions isn't making sense to me. As a minimal example consider,


LogPlot[Sin[x], {x, 0, π}, Epilog -> {Text["x", {π/2, 0.2}]}]

I'd have expected this to put an "x" in the center of the graph but instead it shows up in the corner:


enter image description here


I've also tried ListLogplot and other graphics but they all produce similar results.


How do I force Epilog to use the same positions as the plot?



Note: I'm using Mathematica V10 on Linux.



Answer



As shown by the graphic, the Log is applied on the y-axis, thus you need to apply Log to the y coordinate of your point:


LogPlot[Sin[x], {x, 0, π}, Epilog -> {Text["x", {π/2, Log@0.2}]}]

Mathematica graphics


For completeness purposes as suggested by rcollyer:


LogLinearPlot[Tanh[x], {x, 1, 100}, Epilog -> {Text["x", {Log@10, 0.98}]}]

Mathematica graphics



LogLogPlot[
Sum[i/(x^2 - 2 i 0.99 x + i^2), {i, {1, 10, 100}}], {x, 0.1, 1000},
Epilog -> {Text["x", Log@{10, 10}]}]

Mathematica graphics


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