#! /usr/env/python
"""Simple hexagonal Landlab cellular automaton.
This file defines the HexCTS class, which is a sub-class of
CellLabCTSModel that implements a simple, non-oriented, hex-grid
CA. Like its parent class, HexCTS implements a continuous-time, stochastic,
pair-based CA. The hex grid has 3 principal directions, rather than 2 for a
raster. Hex grids are often used in CA models because of their symmetry.
Created GT Sep 2014
"""
from ..grid import HexModelGrid
from .celllab_cts import CellLabCTSModel
[docs]
class HexCTS(CellLabCTSModel):
"""Class HexCTS implements a non-oriented hex-grid CellLab-CTS model.
HexCTS constructor: sets number of orientations to 1 and calls
base-class constructor.
Parameters
----------
model_grid : Landlab ModelGrid object
Reference to the model's grid
node_state_dict : dict
Keys are node-state codes, values are the names associated with
these codes
transition_list : list of Transition objects
List of all possible transitions in the model
initial_node_states : array of ints (x number of nodes in grid)
Starting values for node-state grid
prop_data : array (x number of nodes in grid) (optional)
Array of properties associated with each node/cell
prop_reset_value : number or object, optional
Default or initial value for a node/cell property (e.g., 0.0).
Must be same type as *prop_data*.
Examples
--------
>>> from landlab import HexModelGrid
>>> from landlab.ca.celllab_cts import Transition
>>> from landlab.ca.hex_cts import HexCTS
>>> mg = HexModelGrid((4, 3), spacing=1.0)
>>> nsd = {0: "yes", 1: "no"}
>>> xnlist = []
>>> xnlist.append(Transition((0, 1, 0), (1, 1, 0), 1.0, "frogging"))
>>> nsg = mg.add_zeros("node", "node_state_grid")
>>> hcts = HexCTS(mg, nsd, xnlist, nsg)
"""
[docs]
def __init__(
self,
model_grid,
node_state_dict,
transition_list,
initial_node_states,
prop_data=None,
prop_reset_value=None,
seed=0,
):
"""HexCTS constructor: sets number of orientations to 1 and calls base-
class constructor.
Parameters
----------
model_grid : Landlab ModelGrid object
Reference to the model's grid
node_state_dict : dict
Keys are node-state codes, values are the names associated with
these codes
transition_list : list of Transition objects
List of all possible transitions in the model
initial_node_states : array of ints (x number of nodes in grid)
Starting values for node-state grid
prop_data : array (x number of nodes in grid) (optional)
Array of properties associated with each node/cell
prop_reset_value : number or object, optional
Default or initial value for a node/cell property (e.g., 0.0).
Must be same type as *prop_data*.
seed : int (default 0)
Seed for random number generator
"""
# Make sure caller has sent the right grid type
if not isinstance(model_grid, HexModelGrid):
raise TypeError("model_grid must be a Landlab HexModelGrid")
# Define the number of distinct cell-pair orientations: here just 1,
# because HexCTS represents a non-oriented CA model.
self.number_of_orientations = 1
# Call the LandlabCellularAutomaton.__init__() method to do the rest of
# the initialization
super().__init__(
model_grid,
node_state_dict,
transition_list,
initial_node_states,
prop_data,
prop_reset_value,
seed,
)