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Edit the stress rules

LTS assignment is data, not code: a decision table evaluated by the rule engine. The segment table lives in bikescore-bna/rules/data/segment_stress.yaml (and the intersection table alongside it). To change the logic, overlay it from a scenario.

Anatomy of a rule set

name: segment_stress
sets:
  motorway_trunk_fcs: [motorway, trunk, motorway_link, trunk_link]
passes:
  - name: seg_stress
    for:
      dir: [ft, tf]          # evaluated once per direction
    rules:
      - id: motorway_trunk
        when:
          adj_fc: $motorway_trunk_fcs   # condition on a named set
        set:
          <dir>_seg_stress: 3            # <dir> expands to ft / tf

Rules are tried in order; the first match sets the output column. $name references a named set; <dir> expands to the current direction. See Stress rules for the full construct reference.

Overlay a rule change in a scenario

A scenario's rule_sets block replaces the matching rule set. For example, to treat a new bike-infrastructure tag as low-stress, add a rule ahead of the default:

type: sparse
version: 1
description: Treat protected two-way tracks as low-stress.
rule_sets:
  segment_stress:
    # … your amended passes/rules here …

$ bikescore-bna score ./aspen-colorado --scenario my-stress.yaml

Because brokenspoke-analyzer is the parity ground truth, validate any rule change against a known city before relying on it — the default rule set is tuned to match the reference exactly (see Validation & parity).