How to put characters in the vise of the X-axis in Julia Gadfly?

Question

I would like to plot a curve (e.g. sine) with the X axis at -pi / 2, 0, pi / 2, but I would like:

• have ticks only at these points;
• have the symbol pi (ie π, π / 2, etc.) in the tick, and not the text "pi", "pi / 2", etc.

How is this possible with Julia Gadfly?

Answer 1

To have ticks at any points. ex, at π/2and πtry this,

julia>plot([sin,cos],0,6, Stat.xticks(ticks=[π/2,π]))

It is impossible to have characters like π as ticks.

Answer 2

Julia supports utf encodings, so to display the pi character you do this

pi = char(960)

960 pi. Gadfly, 960 ( , ). , @sprintf.

:

using Gadfly
using DataFrames

Gadfly.set_default_plot_size(20cm, 12cm)
pi = @sprintf("%s", char(960))
df1 = DataFrame(x=rand(100), y=rand(100), label=s)
plot(df1, x="x", y="y", color="label")