Many thanks to all for contributing to this thread. I felt sure that such a simple problem had been solved, but just couldn’t see it in the array of seemingly different options.
For the record, I’m coming from Mathematica where I’d use SciDraw to solve this problem.
Also for the record, assuming df_r has been read & populated, the code
fig = Figure(; size=(1000, 300))
ax = Axis(fig[1, 1],
xlabel="Easting (m)", ylabel="Inphase (ppm)",
yscale=log10,
yminorticksvisible=true, yminorticks=IntervalsBetween(9),
xtickformat = "{:.0f}",
xminorticksvisible=true, xminorticks=IntervalsBetween(9)
)
scatterlines!(df_r.Mid_E, ifelse.(df_r.FI_01 .> 0, abs.(df_r.FI_01), NaN); color=:blue, linestyle=:solid, markersize=0)
scatterlines!(df_r.Mid_E, abs.(df_r.FI_01); color=:blue, linestyle=:dash, markersize=0)
xlims!(418500,433500)
ylims!(.1, 10000)
fig
produces the desired panel which is
with labelling to be added.