Plots.jl: Bad ticklabels and unicode error for large values with GR

[AndiMD]

This plotting command

using Plots
gr()
plot(1:1000, x->x^6)

spams the REPL with messages
GKS: character ignored due to unicode error

and produces bad ticklabels like this:

My setup:

Plots v1.0.9
Julia Version 1.4.0
OS: Linux (x86_64-pc-linux-gnu)

Thanks!

[AndiMD]

Possibly related, most GR typesetting is broken. Until recently, the following produced a greek alpha. Now, the label does not show up anymore:
plot(1:10,xlabel="\\alpha")

EDIT: Reverting to 1.0.8 fixes both issues. The issue is also valid for 1.0.10

[daschw]

cc: @jheinen

[jheinen]

We should probably make UTF-8 the default. This works:

ENV["GKS_ENCODING"]="utf8"
using Plots
plot(1:1000, x->x^6)

[jheinen]

[daschw]

We should probably make UTF-8 the default.

In Plots or in GR?

[jheinen]

As a short-time solution, I'd define ENV["GKS_ENCODING"]="utf8" before the first GR function is called, e.g. in Plots' _display and _show methods.

[jheinen]

d00920ca0eff8b7c0826246ba16eeb8620195bfd should fix it.

[AndiMD]

Thanks! Plots#master fixes the ticklabels.
However, the label formatting
plot(1:10,xlabel="\\alpha")
is not fixed by that.

[jheinen]

I'll check that - in the meantime (and as a workaround), you can useL"\alpha" (via LaTeXStrings) which works fine.

[AndiMD]

Thanks again. I will simply use 1.0.8 in the meantime, since LaTeXStrings have always looked too pixelated for me

[jheinen]

Ok, so there are still some other problems. I'll check this tomorrow. Plots should use GR's new rendering engine, which - in this case - it does not.

[AndiMD]

Using 1.0.10, the LaTeXStrings actually look decent! Above image is from 1.0.8.

[AndiMD]

I realized that the utf-8 symbols now work plot(1:10,xlabel="α") (instead of "\\alpha").
With that, I think the issue is resolved.

[eike-fokken]

For future reference:
If you have Plots precompiled via PackageCompiler and none of this seems to work for you, the following might help (it helped me):
Prepend your call

julia --sysimage /path/to/sysimage_custom.so

with exporting GKS_ENCODING like so:

export GKS_ENCODING="utf-8" && julia --sysimage /path/to/sysimage_custom.so

I didn't test whether you also need (or don't need) to call these before compiling Plots (whatever I did, in the end it worked) but I think the call to export above is enough.