argscape.visualize()

The visualize() function is the main entry point for creating ARGscape visualizations from tree sequences.

import argscape
import tskit

ts = tskit.load("example.trees")
viz = argscape.visualize(ts, theme="liquid", max_samples=100)
viz.show()  # Opens in browser

Full Function Signature

def visualize(
    ts: tskit.TreeSequence,
    *,
    # Mode
    mode: Literal["force_graph", "spatial_3d"] = "force_graph",
    # Data selection
    max_samples: int | None = None,
    subset_mode: Literal["even", "random"] = "even",
    subset_seed: int | None = None,
    samples: list[int] | tuple[int, int] | None = None,
    genomic_range: tuple[float, float] | None = None,
    temporal_range: tuple[float, float] | None = None,
    # Focal node
    focal_node: int | None = None,
    focal_mode: Literal["subarg", "ancestors"] = "subarg",
    # Appearance
    theme: str | Theme = "liquid",
    width: int = 1200,
    height: int = 800,
    show_controls: bool = False,
    # Custom colors (override theme)
    sample_color: str | None = None,
    internal_color: str | None = None,
    root_color: str | None = None,
    edge_color: str | None = None,
    background_color: str | None = None,
    mutation_color: str | None = None,
    text_color: str | None = None,
    # Nodes
    sample_node_size: int = 8,
    internal_node_size: int = 4,
    root_node_size: int = 6,
    show_sample_ids: bool = False,
    show_internal_ids: bool = False,
    show_root_ids: bool = False,
    color_by_population: bool = False,
    # Edges
    edge_width: float = 1.0,
    edge_opacity: float = 0.6,
    show_edge_labels: bool = False,
    # Mutations
    show_mutations: bool = False,
    mutation_size: int = 6,
    # Layout (2D)
    sample_order: SampleOrderType = "consensus_minlex",
    temporal_spacing: Literal["equal", "linear", "log"] = "equal",
    vertical_spacing: float = 100.0,
    horizontal_spacing: float = 100.0,
    # Spatial (3D)
    shapefile: ShapefileInput = None,
    location_crs: str | None = None,
    shapefile_crs: str | None = None,
    geographic_base: Literal["unit_grid", "eastern_hemisphere", "world"] = "unit_grid",
    temporal_multiplier: float = 12.0,
    spatial_multiplier: float = 160.0,
    # Animation
    animation: TemporalAnimation | GenomicAnimation | tuple[TemporalAnimation, GenomicAnimation] | None = None,
    # Interactive filters
    active_genomic_filter: bool = False,
    active_temporal_filter: bool = False,
) -> VizResult

Parameters

Mode

Parameter	Type	Default	Description
mode	Literal["force_graph", "spatial_3d"]	"force_graph"	Visualization mode. "force_graph" creates a 2D network visualization with D3.js force-directed layout. "spatial_3d" creates a 3D visualization using Three.js, ideal for data with geographic coordinates.

Data Selection

These parameters control which data from the tree sequence is included in the visualization.

Parameter	Type	Default	Description
max_samples	int | None	None	Maximum number of samples to include. If None, all samples are used. Useful for large tree sequences.
subset_mode	Literal["even", "random"]	"even"	How to select samples when max_samples is set. "even" selects evenly spaced samples; "random" selects randomly.
subset_seed	int | None	None	Random seed for reproducibility when using subset_mode="random".
genomic_range	tuple[float, float] | None	None	Genomic position range (start, end) to filter the tree sequence. Only edges within this range are shown.
temporal_range	tuple[float, float] | None	None	Time range (min_time, max_time) to filter nodes. Sample nodes are always kept regardless of this filter.
samples	list[int] | tuple[int, int] | None	None	Direct sample selection. Provide a list of sample node IDs, or a (start, end) tuple for index range. Overrides max_samples when provided.

Examples:

# Visualize 50 evenly-spaced samples from a specific genomic region
viz = argscape.visualize(
    ts,
    max_samples=50,
    subset_mode="even",
    genomic_range=(10000, 20000)
)

# Visualize specific samples by node ID
viz = argscape.visualize(ts, samples=[0, 5, 10, 15, 20])

# Visualize a range of samples (indices 10-50)
viz = argscape.visualize(ts, samples=(10, 50))

# Random subset with reproducible seed
viz = argscape.visualize(ts, max_samples=30, subset_mode="random", subset_seed=42)

Focal Node

These parameters control focused views that show a node and its related nodes (descendants or ancestors).

Parameter	Type	Default	Description
focal_node	int | None	None	Node ID to focus on. If set, shows only this node and its descendants or ancestors based on focal_mode.
focal_mode	Literal["subarg", "ancestors"]	"subarg"	View mode when focal_node is set. "subarg" shows descendants (subtree); "ancestors" shows the path to roots.

Example:

# Show node 42 and all its descendants (subARG)
viz = argscape.visualize(ts, focal_node=42, focal_mode="subarg")

# Show node 10 and all its ancestors
viz = argscape.visualize(ts, focal_node=10, focal_mode="ancestors")

Tip

You can also select focal nodes interactively: left-click a node for subARG view, right-click for ancestors view. See Focal Node Selection for details.

Appearance

Parameter	Type	Default	Description
theme	str | Theme	"liquid"	Color theme. Can be a name ("tskit", "liquid", "grayscale", "paper") or a custom Theme object from argscape.customize_theme(). See Theme Functions for details.
width	int	1200	Visualization width in pixels.
height	int	800	Visualization height in pixels.
show_controls	bool	False	Show quick actions bar and legend in notebook display. When True, enables the interactive control panel with theme switcher, statistics, layout settings, and export options. Always shown in browser via .show().

Example:

# Create a wide, publication-ready visualization
viz = argscape.visualize(ts, theme="paper", width=1600, height=600)

# Enable interactive controls in Jupyter notebook
viz = argscape.visualize(ts, show_controls=True)
viz.display()  # Shows with quick actions bar

Custom Colors

Override specific colors from the chosen theme. All color values should be hex strings (e.g., "#ff0000").

Parameter	Type	Default	Description
sample_color	str | None	None	Override color for sample (leaf) nodes.
internal_color	str | None	None	Override color for internal nodes.
root_color	str | None	None	Override color for root nodes.
edge_color	str | None	None	Override color for edges.
background_color	str | None	None	Override background color.
mutation_color	str | None	None	Override color for mutation markers.
text_color	str | None	None	Override color for text labels.

Example:

# Use paper theme but with custom sample color
viz = argscape.visualize(
    ts,
    theme="paper",
    sample_color="#e63946",  # Red samples
    edge_color="#457b9d",    # Blue-gray edges
)

# Custom colors on dark background
viz = argscape.visualize(
    ts,
    theme="tskit",
    sample_color="#ffd166",  # Gold samples
    mutation_color="#06d6a0", # Teal mutations
)

Tip

For more advanced theme customization, see Theme Functions.

Nodes

Parameter	Type	Default	Description
sample_node_size	int	8	Size of sample nodes in pixels.
internal_node_size	int	4	Size of internal (non-sample, non-root) nodes in pixels.
root_node_size	int	6	Size of root nodes in pixels.
show_sample_ids	bool	False	Whether to display labels on sample nodes.
show_internal_ids	bool	False	Whether to display labels on internal nodes.
show_root_ids	bool	False	Whether to display labels on root nodes.
color_by_population	bool	False	Color nodes by their population assignment instead of by node type (sample/internal/root). Requires tree sequence to have population data assigned to nodes. When enabled, each unique population gets a distinct color using golden-ratio-based hue distribution for visual separation.

Example:

# Larger sample nodes with visible IDs
viz = argscape.visualize(
    ts,
    sample_node_size=12,
    show_sample_ids=True
)

# Color nodes by population
viz = argscape.visualize(
    ts,
    color_by_population=True,
    show_sample_ids=True
)

Edges

Parameter	Type	Default	Description
edge_width	float	1.0	Width of edge lines in pixels.
edge_opacity	float	0.6	Opacity of edges (0.0 to 1.0).
show_edge_labels	bool	False	Whether to display labels on edges showing genomic span.

Example:

# Thicker, more visible edges
viz = argscape.visualize(ts, edge_width=2.0, edge_opacity=0.8)

Mutations

Parameter	Type	Default	Description
show_mutations	bool	False	Whether to display mutation markers on edges.
mutation_size	int	6	Size of mutation markers in pixels.

Example:

# Display mutations
viz = argscape.visualize(ts, show_mutations=True, mutation_size=8)

Layout (2D Force Graph)

These parameters control the layout of the 2D force graph visualization.

Parameter	Type	Default	Description
sample_order	SampleOrderType	"consensus_minlex"	Algorithm for ordering sample nodes horizontally. See sample ordering options below.
temporal_spacing	Literal["equal", "linear", "log"]	"equal"	How to space nodes vertically by time. "equal" gives equal spacing between time points; "linear" is proportional to time; "log" uses logarithmic scaling.
vertical_spacing	float	100.0	Vertical spacing as percentage of available height (0-100).
horizontal_spacing	float	100.0	Horizontal spacing as percentage of available width (0-100).

Sample Order Options

Value	Description
"numeric"	Samples ordered by node ID (0, 1, 2, …)
"first_minlex"	Minlex postorder traversal of the first tree
"center_minlex"	Minlex postorder traversal of the center tree
"consensus_minlex"	Consensus ordering from multiple trees (default, recommended)
"ancestral_path"	Orders by ancestral path similarity
"coalescence"	Orders by coalescence patterns
"dagre"	Minimizes edge crossings using barycenter heuristic

Example:

# Custom layout with log temporal spacing
viz = argscape.visualize(
    ts,
    sample_order="dagre",
    temporal_spacing="log",
    vertical_spacing=80.0
)

Spatial (3D)

These parameters control the 3D spatial visualization mode. They are only relevant when mode="spatial_3d".

Parameter	Type	Default	Description
shapefile	ShapefileInput	None	Custom shapefile for geographic background. Can be a file path (str/Path), GeoDataFrame, or GeoJSON dict.
location_crs	str | None	None	Coordinate Reference System of the tree sequence locations (e.g., "EPSG:4326" for lat/lon).
shapefile_crs	str | None	None	Override CRS for the shapefile if it’s missing or incorrect.
geographic_base	Literal["unit_grid", "eastern_hemisphere", "world"]	"unit_grid"	Built-in geographic shape to use when no shapefile is provided.
temporal_multiplier	float	12.0	Scaling factor for the Z-axis (time dimension) in 3D view.
spatial_multiplier	float	160.0	Scaling factor for the X-Y plane (spatial dimensions) in 3D view.

Geographic Base Options

Value	Description	CRS
"unit_grid"	Abstract 10x10 grid for simulated data	None
"eastern_hemisphere"	Eastern hemisphere map	EPSG:4326
"world"	World map	EPSG:4326

ShapefileInput Type

The shapefile parameter accepts several input types:

from pathlib import Path
import geopandas as gpd

# File path (string)
viz = argscape.visualize(ts, mode="spatial_3d", shapefile="countries.shp")

# File path (Path object)
viz = argscape.visualize(ts, mode="spatial_3d", shapefile=Path("countries.shp"))

# GeoDataFrame
gdf = gpd.read_file("countries.shp")
viz = argscape.visualize(ts, mode="spatial_3d", shapefile=gdf)

# GeoJSON dictionary
geojson = {"type": "FeatureCollection", "features": [...]}
viz = argscape.visualize(ts, mode="spatial_3d", shapefile=geojson)

Example:

# 3D visualization with custom shapefile
viz = argscape.visualize(
    ts,
    mode="spatial_3d",
    shapefile="europe.shp",
    location_crs="EPSG:4326",
    temporal_multiplier=20.0,
    spatial_multiplier=200.0
)

Animation

Configure animations that can be played back in the visualization. Animations are started manually via play button and can be paused/resumed. A minimal play button is always visible when animation is configured, even with show_controls=False.

Parameter	Type	Default	Description
animation	TemporalAnimation | GenomicAnimation | tuple | None	None	Animation configuration. Can be a single animation type, or a tuple of both to enable switching between them.

Animation Classes

from argscape import TemporalAnimation, GenomicAnimation

TemporalAnimation - Animates through time layers:

Attribute	Type	Default	Description
mode	Literal["hide", "glide", "root-to-samples"]	"glide"	Animation mode. "hide" reveals nodes layer by layer; "glide" smoothly expands the visible time range; "root-to-samples" animates from roots down to samples.
rate	float	1.0	Speed in time layers per second.

GenomicAnimation - Slides a window across the genome:

Attribute	Type	Default	Description
window	`int	None`	None
window_trees	`int	None`	None
step	`int	None`	None
overlap	`float	None`	None
rate	float	1.0	Speed in steps per second.

Note

For genomic animation, specify either window (base pairs) or window_trees (tree count), not both. Similarly, specify either step or overlap for advancement, not both.

Examples:

# Temporal animation - glide through time
viz = argscape.visualize(
    ts,
    animation=TemporalAnimation(mode="glide", rate=2.0)
)

# Temporal animation - reveal from roots to samples
viz = argscape.visualize(
    ts,
    animation=TemporalAnimation(mode="root-to-samples", rate=1.5)
)

# Genomic animation - slide 10kb window with 50% overlap
viz = argscape.visualize(
    ts,
    animation=GenomicAnimation(window=10000, overlap=0.5, rate=3.0)
)

# Genomic animation - slide 5 trees at a time
viz = argscape.visualize(
    ts,
    animation=GenomicAnimation(window_trees=5, step=2, rate=2.0)
)

# Both animations configured (user can switch between them)
viz = argscape.visualize(
    ts,
    animation=(
        TemporalAnimation(mode="glide", rate=1.0),
        GenomicAnimation(window=5000, overlap=0.25, rate=2.0)
    )
)

Tip

When show_controls=True, a floating animation panel provides full controls including mode selection, speed adjustment, and progress display. In minimal mode (show_controls=False), only the play button is shown.

Interactive Filters

These parameters control whether the genomic and temporal filter sliders are active (showing a range selection) when the visualization first loads. This is useful for encouraging exploration of the data.

Parameter	Type	Default	Description
active_genomic_filter	bool	False	When True, the genomic filter slider is displayed as active with the full sequence range selected. Users can then adjust the range to explore different genomic regions.
active_temporal_filter	bool	False	When True, the temporal filter slider is displayed as active with the full time range selected. Users can then adjust the range to explore different time periods.

Examples:

# Start with genomic filter active for genome exploration
viz = argscape.visualize(ts, active_genomic_filter=True)
viz.display()

# Start with temporal filter active for time exploration
viz = argscape.visualize(ts, active_temporal_filter=True)
viz.display()

# Start with both filters active
viz = argscape.visualize(
    ts,
    active_genomic_filter=True,
    active_temporal_filter=True
)
viz.display()

Tip

The filter sliders appear at the bottom (genomic) and left (temporal) edges of the visualization. When active, dragging the slider handles adjusts which nodes and edges are highlighted or visible.

Returns

Returns a VizResult object with methods to display or export the visualization.

Raises

• ValueError - If an unknown theme name is provided

• FileNotFoundError - If a shapefile path doesn’t exist

• ImportError - If geopandas is required but not installed (for shapefile loading)

Complete Example

import argscape
import tskit

# Load tree sequence
ts = tskit.load("example.trees")

# Create a fully customized visualization
viz = argscape.visualize(
    ts,
    # Mode
    mode="force_graph",
    # Data selection
    max_samples=100,
    subset_mode="even",
    genomic_range=(0, 50000),
    # Appearance
    theme="paper",
    width=1400,
    height=900,
    # Nodes
    sample_node_size=10,
    internal_node_size=5,
    show_sample_ids=True,
    # Edges
    edge_width=1.5,
    edge_opacity=0.7,
    # Mutations
    show_mutations=True,
    mutation_size=6,
    # Layout
    sample_order="consensus_minlex",
    temporal_spacing="linear",
    vertical_spacing=90.0,
)

# Interactive exploration in browser
viz.show()

# Also display in notebook
viz.display()

# Export multiple formats for publication
viz.export("figures/arg_overview.png", dpi=300)
viz.export("figures/arg_overview.svg")
viz.export("figures/arg_overview.pdf")

See Also

• VizResult - VizResult class methods (show, display, export)

• Focal Node Selection - Focal node selection for subARGs and ancestors

• Themes - Available themes and styling options

• Custom Shapefiles and Coordinate Reference Systems - Advanced geographic configuration