treemap

Lays children out into a treemap: a 2D tiling of rectangles (or circles) whose areas are proportional to a weight.

GoFish exposes two spellings:

• treemap(...) — an operator for use inside .flow(); it tiles the partitioned data of a chart.
• Treemap(children, ...) — the low-level combinator form: it takes an explicit list of pre-data-bound marks and assigns each one its (x, y, w, h).

The two share the same options below.

from gofish import Treemap, circle, datum

# Movie worldwide gross summed per major genre -> [(genre, gross), ...]
nodes = [
    circle(fill=datum(genre), stroke="gray", strokeWidth=1, label=True)
        .bind_data({"worldwideGross": gross}, genre)
    for genre, gross in genres
]

# Each child gets its own circle; Treemap assigns its (x, y, w, h).
# `valueField` reads weights from each child's bound datum.
Treemap(
    nodes,
    valueField="worldwideGross",
    paddingInner=2,
    paddingOuter=2,
    round=True,
).render(w=700, h=420)

Signature

# Operator form (inside .flow())
treemap(**options) -> Operator

# Combinator form (explicit children)
Treemap(children, **options) -> Mark

Parameters

Option	Type	Description
valueField	str	Reads weights from each child's bound datum (bind_data); sums if the datum is a list.
value	Callable	Custom weight accessor (overrides valueField).
paddingInner	float	Padding between sibling rectangles.
paddingOuter	float	Padding around the outer edge of the treemap.
round	bool	Round pixel positions/sizes.
tile	"squarify" | "slice" | "dice" | "binary" | "slicedice" | "squarifyCircle"	Tiling strategy ("squarify" default).
sort	"asc" | "desc" | "none"	Sort leaves by weight before layout ("desc" default).
flipY	bool	When True, mirror the layout top-to-bottom inside the treemap box (default False).
leafIntrinsicRadiusField	str	Optional datum key for radius (pixels in treemap space): each leaf is laid out in a square min(leafW, leafH, 2*radius) so the same value can match across separate treemaps.
x, y	float | Value	Optional position offset for the treemap container.
w, h	float | Value	Optional size for the treemap container (the box tiled into). A float is an explicit pixel size; a Value (e.g. a data-driven size channel that sums a field) scales the box through the layout's scale system — and when several treemaps are faceted side by side, they share one scale so their boxes are proportional. When omitted, the treemap fills its slot.

Notes

• A treemap accepts a flat list of children; for multi-level treemaps, compose by nesting Treemap(...) calls (or add a higher-level wrapper).
• In the combinator form, each child is bound to its row with mark.bind_data(d, key) and a datum(...) channel (e.g. fill=datum(genre)) makes the built-in label show the key.