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). The dynamodels adapter (QLModel) sits apart:
it wraps any fitted qlROM as a dynamodels Model for data assimilation and ntsa. 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). |
charts.compute_pod_basis(Xk, r, Mw=None) |
POD basis of one cluster's centered snapshots, optionally W-weighted. |
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. |
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. |
dynamodels adapter
| Name |
One-liner |
model.QLModel |
Any qlROM as a dynamodels Model (observations H z + c, ensembles, time grid). |