Legend entries don't correspond to the desired plots

[kunalmenda]

Say I plot as follows:

ax = Axis()
push!(ax, Plots.Linear(x0,y0))
push!(ax, Plots.Linear(x1,y1), legendentry="leg1")
push!(ax, Plots.Linear(x2,y2), legendentry="leg2")

The resulting legend will have "leg1" and "leg2" correspond to the first and second lines respectively as opposed to the desired second and third lines. The suggested work around is:

ax = Axis()
push!(ax, Plots.Linear(x0,y0), style="forget plot")
push!(ax, Plots.Linear(x1,y1), legendentry="leg1")
push!(ax, Plots.Linear(x2,y2), legendentry="leg2")

Would it be possible to make "forget plot" a default option?

[tawheeler]

Want to make a branch, make the change, and see whether the behavior has any undesired consequences?

[mykelk]

I think forget plot might not be what we want. I'll take this one on, after it is working in Julia 1.0, which should be by tomorrow.

[mykelk]

Yeah, forget plot is not what we want. It will leave the plot out of the legend (which is good), but it won't advance the cycle list. I think we probably need to go about handling legends differently, perhaps with the \legend command, which allows us to add empty legends as mentioned here. Right now, the implementation uses the \addlegendentry command.

[mossr]

I submitted a PR #153 based on code Mykel passed along to me and got \legend{} working nicely. We can now handle the MWE that Kunal posted (and all examples in the Jupyter notebook passed):

using PGFPlots
x0,y0 = rand(10), rand(10)
x1,y1 = 1:10, 1:10
x2,y2 = 10:-1:1, 1:10
ax = Axis()
push!(ax, Plots.Linear(x0,y0))
push!(ax, Plots.Linear(x1,y1,legendentry="leg1"))
push!(ax, Plots.Linear(x2,y2,legendentry="leg2"))
ax