qlroms

The package core. Geometry is the partition and its coordinate systems — charts, the exact atlas, transition maps — and knows nothing about time. Dynamics is what every family compiles into: the shared step(apod) surface and the common operator machinery (ETDRK4, quadratic steps). import qlroms loads only the geometry; the intrusive family lives in qlroms.intrusive_qlroms.

Geometry

Name	One-liner
charts.fit_clusters(X, K, ...)	k-means partition of the snapshots (full / minibatch, clustering space, overlapping assignment); Euclidean on the features it is given.
charts.clustering_features(X, ..., Mw=None)	The features k-means sees; with Mw plain Euclidean distance on them is the W distance.
charts.compute_pod_basis(Xk, r, Mw=None)	POD basis of one cluster's centered snapshots, optionally W-weighted.
metric	The inner-product weight in one place: wsq, col_norm, CentroidIndex (nearest centroid in the W metric), metric_features, sidecar files for a mass matrix.
charts.Chart	One chart: centroid + local basis (+ Mw); project_state / recover_state.
charts.QuadROM	Family-neutral quadratic member: a Chart with (b, A, B) and the ETDRK4 / discrete step.
atlas.fit_charts(X, K, r, ...)	One-call offline geometry: clustering + per-cluster POD + the exact atlas → Atlas.
atlas.build_global_assimilation_basis(...)	The shared affine space and the chart ↔ atlas maps (Tgk, dgk, Tkg, dkg).
transitions.TransitionMaps	Pairwise chart-to-chart and chart-to-atlas affine maps, and the W-metric distances the switching rule compares.

Dynamics

Name	One-liner
base.qlROMBase, base.qlROM	The compilation of K single-cluster ROMs: step(apod), transition matrix, cluster bookkeeping.
base.free_run(model, x0, n_steps)	Closed-loop forecast from a physical state; returns the trajectory and the chart path.
operators.build_etdrk4_coeffs, quadratic_etdrk4_step, quadratic_map_step	ETDRK4 coefficients for a reduced linear operator, one quadratic ETDRK4 step, one discrete quadratic map step.