Customization

Customize the appearance of your chord diagrams. Parameters are designed to work together: alpha controls opacity; alpha_by_value applies strength-based opacity; focus dimming affects labels, arcs, and ribbons automatically.

Layout Parameters

Control the overall layout:

chordplot!(ax, cooc;
    inner_radius = 0.92,    # Inner radius for ribbons
    outer_radius = 1.0,     # Outer radius for arcs
    arc_width = 0.08,       # Width of arc segments
    gap_fraction = 0.03,    # Gap between arcs
    sort_by = :group,       # :group, :value, or :none
    arc_scale = 1.0,        # Fraction of width for arcs; < 1 adds gaps
    ribbon_width_power = 1.0 # Exponent for ribbon thickness
)

Ribbon thickness (ribbon_width_power): Ribbon widths are scaled as (value/flow)^power. Use a value greater than 1 (e.g. 1.5 or 2.0) to make strong connections visibly thicker and weak ones thinner.

Gaps between arcs (gap_fraction and arc_scale): gap_fraction reserves that fraction of the circle for gaps. arc_scale < 1 adds further separation.

Ribbon Styling

chordplot!(ax, cooc;
    ribbon_tension = 0.5,   # Bezier curve tension (0 = straight, 1 = tight)
    min_ribbon_value = 0    # Hide ribbons below this value
)

Opacity Control

Use alpha to control opacity. It accepts:

• Single value: applies to ribbons, arcs, and labels equally
• Tuple (ribbons, arcs, labels): per-component control
• ComponentAlpha: named fields for clarity

# All components at 70% opacity
chordplot!(ax, cooc; alpha = 0.7)

# Semi-transparent ribbons, solid arcs and labels (tuple)
chordplot!(ax, cooc; alpha = (0.5, 1.0, 1.0))

# Named fields for clarity (recommended)
chordplot!(ax, cooc; alpha = ComponentAlpha(ribbons=0.5, arcs=1.0, labels=1.0))

Default is alpha = 1.0 (fully opaque).

Strength-based Opacity

Use alpha_by_value to scale opacity by strength. It accepts:

• true/false: simple on/off with defaults
• ValueScaling: full control over which components scale

# Scale all components by value
chordplot!(ax, cooc; alpha_by_value = true)

# Full control with ValueScaling
chordplot!(ax, cooc; alpha_by_value = ValueScaling(
    enabled = true,
    components = (true, true, false),  # ribbons, arcs, but not labels
    min_alpha = 0.2,
    scale = :log
))

ValueScaling Fields

• enabled::Bool: Whether scaling is active
• components::NTuple{3,Bool}: Which components scale (ribbons, arcs, labels)
• min_alpha::Float64: Minimum opacity for weakest values (default: 0.1)
• scale::Symbol: :linear or :log scaling

Components set to false remain fully opaque (alpha = 1.0).

Focus (Dim a Subset of Labels)

Set focus_group and focus_labels to highlight specific labels. Non-focused labels in that group are dimmed automatically.

chordplot!(ax, cooc; focus_group = :V_call, focus_labels = ["V1", "V2"])

Arc Styling

chordplot!(ax, cooc;
    arc_width = 0.08,
    arc_strokewidth = 0.5,
    arc_strokecolor = :black
)

Label Customization

chordplot!(ax, cooc;
    show_labels = true,
    label_offset = 0.12,        # Distance from arc
    label_fontsize = 10,
    label_color = :black,       # Use :group to color by category
    rotate_labels = true,       # Rotate to follow arc
    label_justify = :inside     # :inside or :outside
)

Tips for long labels:

• Increase label_offset (e.g., 0.18) to move labels further out
• Use label_justify = :inside to align toward circle center
• Adjust label_fontsize based on figure size