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MajorityPlayerA

Role: Player A that encodes segment-wise majority information from a flattened binary field into a deterministic communication vector.

Location: Q_Sea_Battle.majority_player_a.MajorityPlayerA

Derived constraints

  • Let field_size be self.game_layout.field_size (int, not specified), then \(n2 = \text{field\_size}^2\) (int).
  • Let comms_size be self.game_layout.comms_size (int, not specified), then \(m = \text{comms\_size}\) (int).
  • Segment length is \(\text{segment\_len} = n2 // m\) (int); the implementation assumes \(m\) divides \(n2\) (comment: enforced by GameLayout).

Constructor

Parameter Type Description
game_layout GameLayout, constraints: not specified, shape: N/A Game configuration for this player; stored/used via the PlayerA base class and accessed as self.game_layout.

Preconditions

  • game_layout is a GameLayout instance (not validated here).
  • Additional constraints are not specified in this class.

Postconditions

  • The instance is initialized by delegating to PlayerA.__init__(game_layout).

Errors

  • Not specified (any exceptions would come from PlayerA.__init__ or invalid game_layout usage elsewhere).

Example

from Q_Sea_Battle.game_layout import GameLayout
from Q_Sea_Battle.majority_player_a import MajorityPlayerA

layout = GameLayout(field_size=4, comms_size=4)  # exact signature not specified here
player = MajorityPlayerA(layout)

Public Methods

decide(field, supp=None)

Encode majority statistics in the communication vector.

Parameters

  • field: np.ndarray, dtype: any (converted to int), constraints: interpreted as 0/1 values by documentation but not validated, shape: any (flattened internally to 1D via .ravel()).
  • supp: Optional[Any], constraints: unused, shape: N/A.

Returns

  • np.ndarray, dtype int, constraints: values in {0, 1}, shape (m,), where \(m = \text{comms\_size}\).

Behavior

  • Converts field to flat_field = np.asarray(field, dtype=int).ravel().
  • Computes \(n2 = \text{field\_size}^2\) and \(m = \text{comms\_size}\) from self.game_layout.
  • Sets segment_len = n2 // m.
  • For each segment \(i \in [0, m)\), slices flat_field[start:end] where start = i * segment_len and end = start + segment_len, then sets comm[i] = 1 if ones >= zeros else 0, with ones = int(segment.sum()) and zeros = segment_len - ones.
  • Returns the resulting comm.

Preconditions

  • self.game_layout.field_size and self.game_layout.comms_size exist and are usable as integers.
  • The implementation assumes \(m\) divides \(n2\).
  • field must contain at least n2 elements after flattening; otherwise segment slices may be shorter than segment_len, affecting majority computation (not checked).

Postconditions

  • Returns a newly allocated vector comm of length m.

Errors

  • May raise exceptions from np.asarray(..., dtype=int) for non-coercible inputs.
  • May raise ZeroDivisionError if m == 0 (not prevented here).
  • May raise attribute errors if self.game_layout is missing required attributes.

Example

import numpy as np
from Q_Sea_Battle.majority_player_a import MajorityPlayerA
from Q_Sea_Battle.game_layout import GameLayout

layout = GameLayout(field_size=4, comms_size=4)  # exact signature not specified here
player = MajorityPlayerA(layout)

field = np.array([
    1, 0, 1, 0,
    0, 0, 1, 1,
    1, 1, 0, 0,
    0, 1, 0, 1,
])
comm = player.decide(field)

Data & State

  • Inherited state from PlayerA (not defined in this module).
  • Uses self.game_layout (type: GameLayout, constraints: not specified, shape: N/A) as established by the base class.
  • No additional attributes are defined by MajorityPlayerA.

Planned (design-spec)

  • Not specified (no design notes provided).

Deviations

  • No deviations identified (no design notes provided to compare against code).

Notes for Contributors

  • The method decide computes n2 from field_size rather than from the actual length of field; if field does not match the expected size, behavior is not validated and may silently produce incorrect segment statistics.
  • Majority tie-breaking is implemented as 1 when ones >= zeros.
  • Q_Sea_Battle.players_base.PlayerA (base class; behavior not documented here).
  • Q_Sea_Battle.game_layout.GameLayout (provides field_size and comms_size).

Changelog

  • 0.1: Initial implementation (module docstring version).