"""
Examples
--------
Create a grid of length 2 in the x direction, and 3 in the y direction.
>>> g = Rectilinear([1., 2., 3.], [1., 2., 4., 8.])
>>> g.get_point_count()
12
>>> g.get_cell_count()
6
>>> g.get_x()
array([ 1., 2., 4., 8., 1., 2., 4., 8., 1., 2., 4., 8.])
>>> g.get_y()
array([ 1., 1., 1., 1., 2., 2., 2., 2., 3., 3., 3., 3.])
>>> g.get_shape()
array([3, 4])
Create a grid of length 2 in the i direction, and 3 in the j direction.
>>> g = Rectilinear([1., 2., 4., 8.], [1., 2., 3.], indexing='ij')
>>> g.get_x()
array([ 1., 2., 3., 1., 2., 3., 1., 2., 3., 1., 2., 3.])
>>> g.get_y()
array([ 1., 1., 1., 2., 2., 2., 4., 4., 4., 8., 8., 8.])
>>> g.get_shape()
array([4, 3])
>>> g.get_offset()
array([ 4, 8, 12, 16, 20, 24])
>>> g.get_connectivity()
array([ 0, 1, 4, 3, 1, 2, 5, 4, 3, 4, 7, 6, 4, 5, 8, 7, 6,
7, 10, 9, 7, 8, 11, 10])
**Rectilinear grid of points**
Create a grid of length 2 in the i direction, and 3 in the j direction.
>>> g = RectilinearPoints ([1., 2., 4., 8.], [1., 2., 3.], indexing='ij', set_connectivity=True)
>>> g.get_x()
array([ 1., 2., 3., 1., 2., 3., 1., 2., 3., 1., 2., 3.])
>>> g.get_y()
array([ 1., 1., 1., 2., 2., 2., 4., 4., 4., 8., 8., 8.])
>>> g.get_shape ()
array([4, 3])
>>> g.get_point_count()
12
>>> g.get_cell_count()
0
The offset runs from 1 up to (and including) the number of points.
>>> all (g.get_offset ()==np.arange (1, g.get_point_count ()+1))
True
The connectivity runs from 0 to one less than the number of points.
>>> all (g.get_connectivity ()==np.arange (g.get_point_count ()))
True
**1D Rectilinear grid**
>>> g = Rectilinear([1,3,4,5,6], set_connectivity=True)
>>> g.get_x()
array([ 1., 3., 4., 5., 6.])
>>> g.get_point_count()
5
>>> g.get_cell_count()
4
>>> g.get_connectivity()
array([0, 1, 1, 2, 2, 3, 3, 4])
>>> g.get_offset()
array([2, 4, 6, 8])
**3D Rectilinear grid**
>>> g = Rectilinear ([0, 1], [2, 3], set_connectivity=True, indexing='ij')
>>> g.get_x()
array([ 2., 3., 2., 3.])
>>> g.get_y()
array([ 0., 0., 1., 1.])
>>> g = Rectilinear ([0, 1], [2, 3], [4, 5], set_connectivity=True, indexing='ij')
>>> g.get_x()
array([ 4., 5., 4., 5., 4., 5., 4., 5.])
>>> g.get_y()
array([ 2., 2., 3., 3., 2., 2., 3., 3.])
>>> g.get_z()
array([ 0., 0., 0., 0., 1., 1., 1., 1.])
>>> g.get_point_count()
8
>>> g.get_cell_count()
1
>>> g = Rectilinear([0, 1, 2, 3], [4, 5, 6], [7, 8], set_connectivity=True, indexing='ij')
>>> g.get_x()
array([ 7., 8., 7., 8., 7., 8., 7., 8., 7., 8., 7., 8., 7.,
8., 7., 8., 7., 8., 7., 8., 7., 8., 7., 8.])
>>> g.get_shape()
array([4, 3, 2])
>>> x = g.get_x()
>>> x.shape = g.get_shape()
"""
import numpy as np
from pymt.grids.meshgrid import meshgrid
from .structured import Structured, StructuredPoints
[docs]class RectilinearPoints(StructuredPoints):
def __init__(self, *args, **kwds):
kwds.setdefault("set_connectivity", False)
kwds.setdefault("indexing", "xy")
n_dim = len(args)
if n_dim < 1 or n_dim > 3:
raise ValueError("number of dimensions must be between 1 and 3")
coords = []
for arg in args:
coords.append(np.array(arg, dtype=np.float64))
if n_dim > 1:
XI = meshgrid(*coords, indexing="ij")
else:
XI = [np.array(args[0], dtype=np.float64)]
shape = XI[0].shape
self._x_coordinates = np.array(coords[-1], dtype=np.float64)
try:
self._y_coordinates = np.array(coords[-2], dtype=np.float64)
except IndexError:
pass
try:
self._z_coordinates = np.array(coords[-3], dtype=np.float64)
except IndexError:
pass
args = XI + [shape]
super().__init__(*args, **kwds)
[docs] def get_x_coordinates(self):
"""
Examples
--------
>>> g = Rectilinear([0, 1], [2, 3], [4, 5], set_connectivity=True, indexing='ij')
>>> g.get_x_coordinates()
array([ 4., 5.])
"""
return self._x_coordinates
[docs] def get_y_coordinates(self):
"""
Examples
--------
>>> g = Rectilinear([0, 1], [2, 3], [4, 5], set_connectivity=True, indexing='ij')
>>> g.get_y_coordinates()
array([ 2., 3.])
"""
return self._y_coordinates
[docs] def get_z_coordinates(self):
"""
Examples
--------
>>> g = Rectilinear([0, 1], [2, 3], [4, 5], set_connectivity=True, indexing='ij')
>>> g.get_z_coordinates()
array([ 0., 1.])
"""
return self._z_coordinates
[docs] def get_xyz_coordinates(self):
return (
self.get_x_coordinates(),
self.get_y_coordinates(),
self.get_z_coordinates(),
)
[docs] def get_axis_coordinates(self, axis=None, indexing="ij"):
if indexing != "ij":
raise ValueError("only ij indexing is supported")
if axis is None:
return [
self.get_z_coordinates(),
self.get_y_coordinates(),
self.get_x_coordinates(),
]
else:
n_dims = self.get_dim_count()
if axis >= n_dims:
raise ValueError("axis is greater than number of dimensions")
axis = n_dims - axis - 1
if axis == 0:
return self.get_x_coordinates()
elif axis == 1:
return self.get_y_coordinates()
elif axis == 2:
return self.get_z_coordinates()
[docs]class Rectilinear(RectilinearPoints, Structured):
"""Create a rectilinear grid.
Parameters
----------
x: ndarray
1-D array of x-coordinates of nodes.
y: ndarray
1-D array of y-coordinates of nodes.
shape: tuple of int
Grid shape measured in number of nodes
indexing: {'xy', 'ij'}, optional
Cartesian ('xy', default) or matrix ('ij') indexing of output.
Returns
-------
Rectilinear
An instance of a Rectilinear grid.
"""
def __init__(self, *args, **kwds):
kwds["set_connectivity"] = True
super().__init__(*args, **kwds)
if __name__ == "__main__":
import doctest
doctest.testmod(optionflags=doctest.NORMALIZE_WHITESPACE)
