# How do I flip the r-axis in polar plot?

I want to plot satellite track over a ground station, like how Gpredict and other ground station tool does it:

In that polar plot, for the r-axis, 90 degrees is at the center and 0 degrees is at the edge. In Julia its the other way, 0 is at the center and 90 is at the edge:

I want the plot to look like this, with 0 at the edge and 90 at the center:

I got that by subtracting the r-axis values from 90 degrees, something like this:

``````plot(azimuth[4149:4149+400], 90 .- elevation[4149:4149+400],proj = :polar, ylim=(0,90))
``````

It looks like this might be possible using Makie.jl insteads of Plots.jl: see the example on this page titled “Reoriented Axis”.

In `Plots.jl`, after the above-mentioned data flip transformation, we can deactivate the labeling of the radial axis and then manually annotate it:

``````using Plots; gr()

θ = range(0, 2π, 100)
rθ = 50 .+ 30*cos.(3*θ .- π/6).^3
plot(θ, 90 .- rθ, proj=:polar, c=:blue, yaxis=false, ylims=(0,90))
annotate!(zeros(3), 0:1/3:2/3, text.(string.(90:-30:30), 8, "Computer Modern"))
``````

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