Gaston.jl

Gaston (source code here) is a Julia package for plotting. It provides an interface to gnuplot, a mature, powerful, and actively developed plotting package available on all major platforms.

Gaston emphasizes easy and fast plotting on the screen, notebook or IDE. Knowledge of gnuplot is not required, but some familiarity is beneficial. Gaston also exposes the full power of gnuplot, for more expert users.

using Gaston, SpecialFunctions
x = y = 0:0.075:10
surf(x, y, (x,y) -> besselj0(y)*x^2, with = "pm3d",
     Axes(view = (45, 45),
          pm3d = "lighting primary 0.5 specular 0.4",
          key = :off)
     )

(Image inspired by What's new in gnuplot 5.2?)

Gaston features

Plot using graphical windows, and keeping multiple plots active at a time, with mouse interaction. A browser is not required to show plots.
Plot also directly to the REPL, using text (ASCII) or sixels.
Plot in Jupyter, Juno or VS Code.
"Recipes" to generate common 2-D and 3-D plots, such as stem plots, histograms, images, surfaces, contour and heatmaps.
Easy definition of custom plotting commands for specific types, or with specific defaults.
Save plots to multiple formats, including pdf, png and svg.
Color palettes from ColorSchemes.jl.
Export plots for integration into Latex documents.
A simple interface to almost the full power of gnuplot, for users who have more experience with it.
Fast first plot: load package, plot, and save to pdf in less than six seconds. Subsequent plots take a few hundreds of milliseconds.
A simple interface to manage multiple plots, using commands such as figure(), closeall(), etc.

Gaston and Gnuplot.jl: two philosophies

Gnuplot.jl is another front-end for gnuplot, with comparable capabilities to Gaston. An example serves to illustrate the differences in how the two packages approach the interface problem. Consider this example plot:

x = 1:0.1:10
@gp    "set grid" "set key left" "set logscale y"
@gp :- "set title 'Plot title'" "set label 'X label'" "set xrange [0:*]"
@gp :- x x.^0.5 "w l tit 'Pow 0.5' dt 2 lw 2 lc rgb 'red'"
@gp :- x x      "w l tit 'Pow 1'   dt 1 lw 3 lc rgb 'blue'"
@gp :- x x.^2   "w l tit 'Pow 2'   dt 3 lw 2 lc rgb 'purple'"

This shows that Gnuplot.jl essentially allows one to write gnuplot commands directly in Julia. The same plot in Gaston would be:

x = 1:0.1:10
plot(x, x.^0.5,
     w = "l",
     legend = "'Pow 0.5'",
     dt = 2,
     lw = 2,
     lc = :red,
     Axes(grid = :on,
          key = "left",
          axis = "semilogy"))
plot!(x, x,
      w = :l,
      leg = :Pow_1,
      dt = 1,
      lw = 3,
      lc = :blue)
plot!(x, x.^2,
      curveconf = "w l tit 'Pow 2' dt 3 lw 2 lc 'purple'")

In summary, Gaston offers a function-based interface, and gnuplot commands can be specified in a few different ways, with convenient notation, such as the optional use of "legend" instead of gnuplot's "title", symbols to avoid typing quote marks (") all the time, and others that are described later in this document.

Installation

Gaston requires Julia version 1.3.0 or above, and requires Gnuplot version 5.0 or above (version 5.2.8 is recommended). You should install gnuplot on your system prior to using Gaston. On Linux, it is highly recommended that you select a version with support for Qt: on Debian and Ubuntu, you will need gnuplot-qt.

To install Gaston from the Julia REPL, run

julia> ]add Gaston

Typing ] switches the Julia REPL to the package manager, and the add command installs the package. To exit the package manager, hit the backspace key.

Gnuplot configuration

Gaston respects user configuration settings in gnuplot's startup file. Left un-configured, gnuplot's plots are less than attractive. The following minimum configuration is suggested (and was used to generate the plots in this document):

set linetype 1 lc rgb "blue" pt 3
set linetype 2 lc rgb "red" pt 4
set linetype 3 lc rgb "green" pt 6
set linetype 4 lc rgb "black" pt 12
set linetype 5 lc rgb "blue" pt 5
set linetype 6 lc rgb "red" pt 1
set linetype 7 lc rgb "green" pt 2
set linetype 8 lc rgb "black" pt 7
set linetype cycle 8
set style data lines
set key noautotitle
set auto fix
set offsets graph .05, graph .05, graph .05, graph .05

The configuration file is ~/.gnuplot in Unix-like systems, and %APPDATA%\GNUPLOT.INI in Windows.

Next steps

Load Gaston into your Julia session with

using Gaston

The Introduction to plotting has more information about basic use and configuration.

There is a 2-D plotting tutorial and a 3-D plotting tutorial.

The Extending Gaston section explains how to extend Gaston by creating your own "recipes", both for specific kinds of plots, and for plotting data of specific types.

There is a section on Managing multiple figures and all related commands.

The 2-D Examples and 3-D Examples pages show many plotting examples – because sometimes a bit of code is worth one thousand words.

The Usage notes and FAQ section includes additional usage examples and answers frequent questions.

Gnuplot resources

These websites have more information on gnuplot and how to use it:

Running tests

Gaston includes an extensive test suite, which can executed with:

julia> ]test Gaston

All tests should pass (but a few may be skipped).

Support

Please post support questions to Julia's discuss forum.

Contributing

Bug reports, suggestions and pull requests are welcome at Gaston's github page