.. Auto-generated by scripts/generate_problem_catalog_docs.py. Do not edit by hand.

Planar roof truss grammar (seven-point symmetric variant)
=========================================================

A roof-truss grammar aligned to the seven-point symmetric loading formulation reported in the structural essay study.

See :doc:`../grammar` for the grammar family index.

Quick Facts
-----------

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   * - Field
     - Value
   * - Problem ID
     - ``planar_roof_truss_seven_point_symmetric``
   * - Problem Family
     - grammar
   * - Implementation
     - ``design_research_problems.problems.grammar._planar_truss:PlanarTrussSpanProblem``
   * - Capabilities
     - ``discrete-actions``, ``external-adapter``, ``optional-evaluator``, ``serializable-state``, ``statement-markdown``
   * - Study Suitability
     - none
   * - Tags
     - ``grammar``, ``truss``, ``roof``, ``discrete``, ``topology``, ``symmetric``

Taxonomy
--------

Formulation
   discrete_grammar
Convexity
   not_applicable
Design Variable Type
   discrete
Is Dynamic
   no
Orientation
   engineering_practical
Feasibility Ratio Hint
   0.25
Objective Mode
   single
Constraint Nature
   hard
Bounds Summary
   symmetric planar roof-truss topology with seven fixed roof load points
Tags
   ``grammar``, ``truss``, ``roof``, ``discrete``, ``topology``, ``symmetric``

Statement
---------

This catalog entry approximates the sixth planar roof-truss formulation from the structural essay study: seven uniformly spaced fixed roof load points with left-right symmetry enforced.

The state begins with pinned and roller supports plus seven loaded roof joints. Interior joints and members are edited through mirrored actions so the topology remains symmetric about the roof apex.

Problem Shape
-------------

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   * - Field
     - Value
   * - State Type
     - PlanarTrussState
   * - Initial Transition Count
     - 23
   * - Initial Rule Names
     - ``add_joint``, ``add_joint_pair``, ``add_member``

Manifest Parameters
-------------------

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   * - Key
     - Value
   * - candidate_point_fractions
     - [[0.18, 0.2], [0.34, 0.32], [0.5, 0.2]]
   * - enforce_symmetry
     - yes
   * - load_magnitude
     - 1000
   * - max_height
     - 2.5
   * - roof_load_x_fractions
     - [0.125, 0.25, 0.375, 0.5, 0.625, 0.75, 0.875]
   * - span
     - 10

Initial Transition Summary
--------------------------

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   * - Rule Name
     - Transition Count
   * - add_joint
     - 1
   * - add_joint_pair
     - 2
   * - add_member
     - 20

Library Interface
-----------------

- ``initial_state()``
- ``enumerate_transitions(state)``
- ``enumerate_next_states(state)``
- ``evaluate(state)``