Plot Attributes and Color Palettes

Introduction to Data Visualization with Julia

Gustavo Vieira Suñe

Data Analyst

Color palettes

Many color palettes, including

A figure previewing different Julia color palettes.

¹ https://juliagraphics.github.io/ColorSchemes.jl/stable/catalogue/

Using palettes

# Set the theme
theme(:bright)


# Create a scatter plot
scatter(
    streaming.Age,
    streaming."Frequency [K pop]",
    group=streaming."Frequency [K pop]",
    label=false,

    # Set color palette
    palette=:Dark2_5
)

xlabel!("Age")
ylabel!("Frequency of Play")

A scatter plot depicting the frequency of respondents' K-Pop listening habits against their age.

Plot attributes

Previously encountered:

title, xlabel, ylabel
xticks, yticks
color
linecolor, linewidth
markercolor
framestyle

Many more:

xlims, ylims
alpha
linestyle
legend_title, legend_position
markersize, markershape

...

¹ https://docs.juliaplots.org/stable/attributes/#attributes

Marker attributes

theme(:bright)

scatter(
    streaming.Age,
    streaming."Frequency [K pop]",
    group=streaming."Frequency [K pop]",
    label=false,
    palette=:Dark2_5

    # Marker attributes
    markershape=:diamond,
    markersize=8,
)

xlabel!("Age")
ylabel!("Frequency of Play")

A scatter plot depicting the frequency of respondents' K-Pop listening habits against their age, with large diamond-shaped markers.

Opacity/Transparency

theme(:bright)

scatter(
    streaming.Age,
    streaming."Frequency [K pop]",
    group=streaming."Frequency [K pop]",
    label=false,
    palette=:Dark2_5
    markershape=:diamond,
    markersize=8,

    # Opacity
    alpha=0.25
)

xlabel!("Age")
ylabel!("Frequency of Play")

A scatter plot depicting the frequency of respondents' K-Pop listening habits against their age, with large diamond-shaped markers with some transparency.

Line attributes

# Set theme and default line width
theme(:dao, linewidth=4)

# Create histogram
histogram(streaming.BPM, label="Observed", 
    color=:lightslateblue, normalize=true)

# Add density plot
density!(streaming.BPM,
    label="Distribution", linecolor=:green2,

    # Line style
    linestyle=:dash)

xlabel!("BPM")
ylabel!("Probability")

A normalized histogram depicting the preferred beats per minute of the survey respondents with a density plot added to visualize the estimated distribution.

Axis bounds and legend attributes

theme(:dao, linewidth=4)

histogram(streaming.BPM, label="Observed", 
    color=:lightslateblue, normalize=true)
density!(streaming.BPM, label="Distribution",
    linecolor=:green2, linestyle=:dash

    # Customize legend
    legend_title="Type",
    legend_position=:topright)

# Set the x-axis bounds
xlims!(50, 230)

xlabel!("BPM")
ylabel!("Probability")

A normalized histogram depicting the preferred beats per minute of the survey respondents with a density plot added to visualize the estimated distribution.

Cheat sheet

Color palettes
- plot(..., palette=palette_symbol)
Marker attributes
- markersize
- markershape

A figure previewing marker shapes available in Plots.jl.

Opacity: alpha=opacity_value
Axis bounds: xlims!(), ylims!()

Line attribute: linetyle
Legend attributes
- legend_title
- legend_position (:right, :left, :top, :bottom, :topright, :topleft, ...)

Let's practice!

Introduction to Data Visualization with Julia