potential_flow_cylinder — DRIVE swarmflow op

• Data kinds: signal × signal × any → table

• Call: import fullseye as fs; fs.ledger.potential_flow_cylinder(x, y, cylinder, speed: 'float' = 1.0, grid: 'bool' = False) -> 'dict' (to call the implementation directly, import swarmflow; swarmflow.potential_flow_cylinder(x, y, cylinder, speed: 'float' = 1.0, grid: 'bool' = False) -> 'dict'; from the registry, opsdrive.get("potential_flow_cylinder"))

Usage

Potential flow around a cylinder (closed form). u − i v = U (1 − R²/(z − z_c)²); NaN inside the circle.

If grid=True, x/y are treated as grid axes (1-D, rows in y order), and a velocity-field dict (module convention) is returned. The default grid=False returns u, v, inside element-wise (broadcast to the same shape) —— it does not guess from the shape whether the inputs are axes or a point list (1-D x and y of the same length can be read either way, and a point list would silently become a grid). Both add stagnation (the upstream stagnation point (x_c − R, y_c)), rear_stagnation and surface_speed_max (= 2U).

Empty input (x with 0 elements) raises ValueError.

References (sample data, literature)

• Sample-data catalog (download URLs / licences) — 2-D uses skimage.data (BSD/public domain) plus synthetic images; 3-D lists download URLs for real data sources (Stanford, PDS, …).

• Operator provenance and references — the sources of the research/methods this op family came from.

• The canonical algorithm (author, year) and its uses are named in the family usage guide above.

Runnable examples (verified samples that actually call this op)

• poc_swarm_obstacle_from_flow — py -3.11 examples/poc_swarm_obstacle_from_flow.py

Ops the type connects to (they accept table as input)

course_layout · course_occupancy · course_contains · world_build · world_camera · world_move · lidar_scan · rss_longitudinal_same

Same category (swarmflow)

sph_kernel · sph_density_pressure · swarm_simulate · swarm_render_overhead · swarm_field_from_tracks · swarm_field_from_piv · velocity_deficit_map · stagnation_from_centerline


*Provenance: swarmflow.py — DRIVE operator registry. This per-op note is generated by tools/opdocs.py md (do not hand-edit).*

© 2026 Kazufumi Furuse — Fullseye operator documentation. Licensed under Apache-2.0.