#! /usr/env/python
"""Python implementation of :class:`~.FramedVoronoiGrid`, a grid class used to create and
manage unstructured Voronoi-Delaunay grids for 2D numerical models, with a structured
perimeter layout
Do NOT add new documentation here. Grid documentation is now built in a
semi- automated fashion. To modify the text seen on the web, edit the
files `docs/text_for_[gridfile].py.txt`.
.. codeauthor:: sebastien lenard
"""
import numpy
from ..graph import DualFramedVoronoiGraph
from .base import ModelGrid
[docs]
class FramedVoronoiGrid(DualFramedVoronoiGraph, ModelGrid):
"""A grid of Voronoi Delaunay cells with a structured perimeter layout.
This inherited class implements a irregular 2D grid with Voronoi Delaunay cells and
irregular patches. It is a special type of :class:`~.VoronoiDelaunayGrid` grid in which
the initial set of points is arranged in a fixed lattice (e.g. like a
:class:`~.RasterModelGrid`), named here "layout", and the core points are
then moved a random distance from their initial positions, bounded by a user-supplied
threshold.
Examples
--------
Create a grid with 3 rows and 2 columns of nodes.
>>> from landlab import FramedVoronoiGrid
>>> grid = FramedVoronoiGrid((3, 2), xy_spacing=1.0)
>>> grid.number_of_nodes
6
>>> grid = FramedVoronoiGrid(
... (4, 3), xy_spacing=(10.0, 10.0), xy_min_spacing=(5.0, 5.0), seed=200
... )
>>> grid.status_at_node.reshape(grid.shape)
array([[1, 1, 1],
[1, 0, 1],
[1, 0, 1],
[1, 1, 1]], dtype=uint8)
>>> grid.x_of_node[3]
0.0
>>> grid.x_of_node[5]
20.0
>>> grid.y_of_node[0::3]
array([ 0. , 7.499, 17.499, 30. ])
>>> grid = FramedVoronoiGrid(
... (3, 5), xy_spacing=(10.0, 10.0), xy_min_spacing=5.0, seed=None
... )
>>> grid.boundary_nodes
array([ 0, 1, 2, 3, 4, 5, 9, 10, 11, 12, 13, 14])
"""
# Inheritance diagram:
#
# FramedVoronoiGrid
# |-- ModelGrid
# `-- DualFramedVoronoiGraph
# |-- FramedVoronoiGraph (Layout: HorizontalRectVoronoiGraph)
# | `-- DelaunayGraph
# `-- DualGraph (use of static Graph.sort())
[docs]
def __init__(
self,
shape,
xy_spacing=(1.0, 1.0),
xy_of_lower_left=(0.0, 0.0),
xy_min_spacing=(0.5, 0.5),
seed=200,
xy_of_reference=(0.0, 0.0),
xy_axis_name=("x", "y"),
xy_axis_units="-",
):
"""Create a grid of voronoi cells with a structured perimeter.
Create an irregular 2D grid with voronoi cells and triangular patches.
It is a special type of :class:`~.VoronoiDelaunayGrid` in which the initial set
of points is arranged in a regular lattice determined by the parameters
*shape*, and *xy_spacing*. The coordinates of
the core points are then randomly moved while the perimeter points
remaining fixed, in a way determined by the parameters *xy_min_spacing*, and
*seed*.
Parameters
----------
shape : tuple of int
Number of rows and columns of nodes.
xy_spacing : float or tuple of float, optional
Node spacing along x and y coordinates. If ``float``, same spacing at *x* and *y*.
xy_of_lower_left : tuple, optional
Minimum *x*-of-node and *y*-of-node values. Depending on the grid,
there may not be a node at this coordinate.
xy_min_spacing: float or tuple of float, optional
Final minimal spacing between nodes. Random moves of the core nodes
from their initial positions cannot be above this threshold:
``(xy_spacing - xy_min_spacing) / 2``
If ``float``, same minimal spacing for *x* and *y*.
seed: int, optional
Seed used to generate the random *x* and *y* moves.
When set, controls the pseudo-randomness of moves to ensure
reproducibility.
When ``None``, the seed is random and the moves of coordinates are
completely random.
xy_of_reference : tuple, optional
Coordinate value in projected space of the reference point,
*xy_of_lower_left*.
xy_axis_name: tuple of str, optional
*x* and *y* axis names.
xy_axis_units: str, optional
*x* and *y* axis units.
Returns
-------
FramedVoronoiGrid
A newly-created grid.
Examples
--------
Create a grid with 3 rows and 2 columns of nodes.
>>> from landlab import FramedVoronoiGrid
>>> grid = FramedVoronoiGrid((3, 2), xy_spacing=1.0)
>>> grid.number_of_nodes
6
"""
DualFramedVoronoiGraph.__init__(
self,
shape,
xy_spacing=xy_spacing,
xy_of_lower_left=xy_of_lower_left,
sort=True,
xy_min_spacing=xy_min_spacing,
seed=seed,
)
ModelGrid.__init__(
self,
xy_axis_name=xy_axis_name,
xy_axis_units=xy_axis_units,
xy_of_reference=xy_of_reference,
)
self._node_status = numpy.full(
self.number_of_nodes, self.BC_NODE_IS_CORE, dtype=numpy.uint8
)
self._node_status[self.perimeter_nodes] = self.BC_NODE_IS_FIXED_VALUE
[docs]
@classmethod
def from_dict(cls, kwds):
args = ()
return cls(*args, **kwds)