Layout Configuration

Advanced control over chord diagram layout.

Custom Layout

Compute layouts manually for advanced control:

config = LayoutConfig(
    inner_radius = 0.75,    # Ribbon attachment radius
    outer_radius = 1.0,     # Arc outer radius
    gap_fraction = 0.05,    # Gap between arcs
    start_angle = π/2,      # Start at top (0 = right)
    direction = 1,          # 1 = counterclockwise, -1 = clockwise
    sort_by = :group        # :group, :value, or :none
)

layout = compute_layout(cooc, config)

What is a custom layout? A custom layout allows you to control how labels are arranged around the circle, how arcs are sized, and the spacing between elements. This gives you fine-grained control over the visual appearance beyond the default settings.

What this shows: This example demonstrates several layout customizations applied together:

sort_by=:value - Labels are sorted by their total flow (largest first), so the most connected labels get the largest arcs and appear first. Compare this to the basic example where labels are sorted by group - here, the most important labels are visually emphasized.
inner_radius=0.85 - Ribbons start closer to the center (default is 0.92), creating more space between ribbon endpoints and the outer circle. This gives a different visual balance and can help when you have many connections.
gap_fraction=0.05 - Slightly larger gaps between arc segments (default is 0.03), making individual arcs more distinct and easier to identify.

These settings work together to create a layout that emphasizes the most important labels and creates a different visual hierarchy compared to the default group-sorted layout.

Sorting Options

:group - Keep groups together, sort within groups by value (default)
:value - Sort all labels by total flow (descending)
:none - Use original order

Accessing Layout Data

layout = compute_layout(cooc)

# Get information
narcs(layout)      # Number of arcs
nribbons(layout)   # Number of ribbons

# Access arcs
for arc in layout.arcs
    println("Label $(arc.label_idx): $(arc.start_angle) to $(arc.end_angle)")
end

# Access ribbons
for ribbon in layout.ribbons
    println("Connection: $(ribbon.source.label_idx) → $(ribbon.target.label_idx), value: $(ribbon.value)")
end