The Topology (xentica.core.topology)¶
This package helps you build the topology for CA models.
All xentica.core.CellularAutomaton
subclasses must have
Topology
class declared inside. This class describes:
dimensions
: the number of dimensions your CA model operates on.lattice
: the type of lattice of your CA board. Builtin lattice types are available inxentica.core.topology.lattice
module.neighborhood
: the type of neighborhood for a single cell. Builtin neighborhood types are available inxentica.core.topology.neighborhood
module.border
: the type of border effect, e.g. how to process offboard cells. Builtin border types are available inxentica.core.topology.border
module.
For example, you can declare the topology for a 2dimensional orthogonal lattice with Moore neighborhood wrapped to a 3torus, as follows:
class Topology:
dimensions = 2
lattice = core.OrthogonalLattice()
neighborhood = core.MooreNeighborhood()
border = core.TorusBorder()
Lattice (xentica.core.topology.lattice)¶
The collection of classes describing different lattice topologies.
All classes there are intended for use inside Topology
for
lattice
class variable definition. They are also available via
xentica.core
shortcut. The example:
from xentica.core import CellularAutomaton, OrthogonalLattice
class MyCA(CellularAutomaton):
class Topology:
lattice = OrthogonalLattice()
# ...
# ...

class
xentica.core.topology.lattice.
Lattice
¶ Bases:
xentica.core.mixins.DimensionsMixin
,xentica.core.mixins.BscaDetectorMixin
The base class for all lattices.
For correct behavior, lattice classes should be inherited from this class. You should also implement the following functions:
See the detailed description below.

coord_to_index_code
(coord_prefix)¶ Generate C code for obtaining the cell’s index by coordinates.
This is an abstract method, you must implement it in
Lattice
subclasses.Parameters: coord_prefix – The prefix for variables, containing coordinates. Returns: A string with the C code calculating cell’s index. No assignment, only a valid expression needed.

index_to_coord
(idx, bsca)¶ Obtain the cell’s coordinates by its index, in pure Python.
This is an abstract method, you must implement it in
Lattice
subclasses.Parameters:  idx – Cell’s index, a positive integer, or a NumPy array of indices.
 bsca –
xentica.core.CellularAutomaton
instance, to access the field’s size and number of dimensions.
Returns: Tuple of integer coordinates, or NumPy arrays of coords per each axis.

index_to_coord_code
(index_name, coord_prefix)¶ Generate C code to obtain coordinates by the cell’s index.
This is an abstract method, you must implement it in
Lattice
subclasses.Parameters:  index_name – The name of a variable containing the cell’s index.
 coord_prefix – The prefix for resulting variables, containing coordinates.
Returns: A string with the C code, doing all necessary to process the index variable and store coordinates to variables with the given prefix.

is_off_board_code
(coord_prefix)¶ Generate C code to test if the cell’s coordinates are off board.
This is an abstract method, you must implement it in
Lattice
subclasses.Parameters: coord_prefix – The prefix for variables, containing coordinates. Returns: A string with the C code testing coordinates’ variables. No assignment, only a valid expression with boolean result needed.

width_prefix
= '_w'¶ The prefix to be used in C code for field size constants.


class
xentica.core.topology.lattice.
OrthogonalLattice
¶ Bases:
xentica.core.topology.lattice.Lattice
Ndimensional orthogonal lattice.
Points are all possible positive integer coordinates.

coord_to_index_code
(coord_prefix)¶ Generate C code for obtaining the cell’s index by coordinates.
See
Lattice.coord_to_index_code()
for details.

index_to_coord
(idx, bsca)¶ Obtain the cell’s coordinates by its index, in pure Python.
See
Lattice.index_to_coord()
for details.

index_to_coord_code
(index_name, coord_prefix)¶ Generate C code for obtaining the cell’s index by coordinates.
See
Lattice.index_to_coord_code()
for details.

is_off_board_code
(coord_prefix)¶ Generate C code to test if the cell’s coordinates are off board.
See
Lattice.is_off_board_code()
for details.

supported_dimensions
= [1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65, 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, 80, 81, 82, 83, 84, 85, 86, 87, 88, 89, 90, 91, 92, 93, 94, 95, 96, 97, 98, 99]¶ Overridden value for supported dimensions.

Neighborhood (xentica.core.topology.neighborhood)¶
The collection of classes describing different neighborhood topologies.
All classes there are intended for use inside Topology
for
neighborhood
class variable definition. They are also available via
xentica.core
shortcut. The example:
from xentica.core import CellularAutomaton, MooreNeighborhood
class MyCA(CellularAutomaton):
class Topology:
neighborhood = MooreNeighborhood()
# ...
# ...

class
xentica.core.topology.neighborhood.
Neighborhood
¶ Bases:
xentica.core.mixins.DimensionsMixin
The base class for all neighborhood topologies.
For correct behavior, neighborhood classes should be inherited from this class. You should also implement the following functions:
See the detailed description below.

neighbor_coords
(index, coord_prefix, neighbor_prefix)¶ Generate the C code to obtain neighbor coordinates by its index.
This is an abstract method, you must implement it in
Neighborhood
subclasses.Parameters:  index – Neighbor’s index, a nonnegative integer less than the number of neighbors.
 coord_prefix – The prefix for variables containing main cell’s coordinates.
 neighbor_prefix – The prefix for resulting variables containing neighbor coordinates.
Returns: A string with the C code doing all necessary to get neighbor’s state from the RAM. No assignment, only a valid expression needed.

neighbor_state
(neighbor_index, state_index, coord_prefix)¶ Generate the C code to obtain a neighbor’s state by its index.
This is an abstract method, you must implement it in
Neighborhood
subclasses.Parameters:  neighbor_index – Neighbor’s index, a nonnegative integer less than the number of neighbors.
 state_index – State’s index, a nonnegative integer less than the number of neighbors for buffered states or 1 for main state.
 coord_prefix – The prefix for variables containing neighbor coordinates.
Returns: A string with the C code doing all necessary to process neighbor’s coordinates and store them to neighbor’s coordinates variables.

num_neighbors
= None¶ Number of neighbors, you must redefine it in subclasses.

topology
= None¶ A reference to
Topology
holder class, will be set inBSCA
metaclass.


class
xentica.core.topology.neighborhood.
OrthogonalNeighborhood
¶ Bases:
xentica.core.topology.neighborhood.Neighborhood
The base class for neighborhoods on an orthogonal lattice.
It is implementing all necessary
Neighborhood
abstract methods, the only thing you should override isdimensions()
setter. Indimensions()
, you should correctly setnum_neighbors
and_neighbor_deltas
attributes.
neighbor_coords
(index, coord_prefix, neighbor_prefix)¶ Generate the C code to obtain neighbor coordinates by its index.
See
Neighborhood.neighbor_coords()
for details.

neighbor_state
(neighbor_index, state_index, coord_prefix)¶ Generate the C code to obtain a neighbor’s state by its index.
See
Neighborhood.neighbor_coords()
for details.

supported_dimensions
= [1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65, 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, 80, 81, 82, 83, 84, 85, 86, 87, 88, 89, 90, 91, 92, 93, 94, 95, 96, 97, 98, 99]¶ Any number of dimentions is supported, 100 is just to limit your hyperspatial hunger.


class
xentica.core.topology.neighborhood.
MooreNeighborhood
¶ Bases:
xentica.core.topology.neighborhood.OrthogonalNeighborhood
Ndimensional Moore neighborhood implementation.
The neighbors are all cells, sharing at least one vertex.

dimensions
¶ Get a number of dimensions.


class
xentica.core.topology.neighborhood.
VonNeumannNeighborhood
¶ Bases:
xentica.core.topology.neighborhood.OrthogonalNeighborhood
Ndimensional Von Neumann neighborhood implementation.
The neighbors are adjacent cells in all possible orthogonal directions.

dimensions
¶ Get a number of dimensions.

Border (xentica.core.topology.border)¶
The collection of classes describing different types of field’s borders.
All classes there are intended for use inside Topology
for
border
class variable definition. They are also available via
xentica.core
shortcut. The example:
from xentica.core import CellularAutomaton, TorusBorder
class MyCA(CellularAutomaton):
class Topology:
border = TorusBorder()
# ...
# ...

class
xentica.core.topology.border.
Border
¶ Bases:
xentica.core.mixins.DimensionsMixin
The base class for all types of borders.
You should not inherit your borders directly from this class, use either
WrappedBorder
orGeneratedBorder
base subclasses instead.

class
xentica.core.topology.border.
WrappedBorder
¶ Bases:
xentica.core.topology.border.Border
The base class for borders that wraps the field into different manifolds.
For correct behavior, you should implement
wrap_coords()
method.See the detailed description below.

wrap_coords
(coord_prefix)¶ Generate C code to translate offboard coordinates to onboard ones.
This is an abstract method, you must implement it in
WrappedBorder
subclasses.Parameters: coord_prefix – The prefix for variables containing the cell’s coordinates.


class
xentica.core.topology.border.
GeneratedBorder
¶ Bases:
xentica.core.topology.border.Border
The base class for borders that generates states of the offboard cells.
For correct behavior, you should implement
off_board_state()
method.See the detailed description below.

off_board_state
(coord_prefix)¶ Generate C code to obtain offboard cell’s state.
This is an abstract method, you must implement it in
GeneratedBorder
subclasses.Parameters: coord_prefix – The prefix for variables containing the cell’s coordinates.


class
xentica.core.topology.border.
TorusBorder
¶ Bases:
xentica.core.topology.border.WrappedBorder
Wraps the entire field into Ntorus manifold.
This is the most common type of border, allowing you to generate seamless tiles for wallpapers.

supported_dimensions
= [1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65, 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, 80, 81, 82, 83, 84, 85, 86, 87, 88, 89, 90, 91, 92, 93, 94, 95, 96, 97, 98, 99]¶ Any number of dimentions is supported, 100 is just to limit your hyperspatial hunger.

wrap_coords
(coord_prefix)¶ Implement coordinates wrapping to torus.
See
WrappedBorder.wrap_coords()
for details.


class
xentica.core.topology.border.
StaticBorder
(value=0)¶ Bases:
xentica.core.topology.border.GeneratedBorder
Generates a static value for every offboard cell.
This is acting like your field is surrounded by cells with the same predefined state.
The default is just an empty (zero) state.

off_board_state
(coord_prefix)¶ Impement offboard cells’ values obtaining.
See
GeneratedBorder.off_board_state()
for details.

supported_dimensions
= [1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65, 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, 80, 81, 82, 83, 84, 85, 86, 87, 88, 89, 90, 91, 92, 93, 94, 95, 96, 97, 98, 99]¶
