""" A CrossSection """
from typing import List, Optional
import numpy as np
from pydantic.v1 import Field
from .base_model import BaseModel, _array, cached_property
from .cell import Cell, _create_full_material_array, _sort_structures
from .environment import Environment
from .mesh import Mesh2D
from .structures import Structure2D
[docs]class CrossSection(BaseModel):
"""A `CrossSection` is created from the association of a `Cell` with an `Environment`,
which uniquely defines the refractive index everywhere."""
structures: List[Structure2D] = Field(
description="the 2D structures in the CrossSection"
)
mesh: Mesh2D = Field(description="the mesh to discretize the structures with")
env: Environment = Field(
description="the environment for which the cross sectionw was calculated"
)
[docs] @classmethod
def from_cell(cls, *, cell: Cell, env: Environment):
cs = cls(structures=cell.structures_2d, mesh=cell.mesh, env=env)
cs._cache["cell"] = cell
return cs
@cached_property
def materials(self):
materials = {}
for i, structure in enumerate(_sort_structures(self.structures), start=1):
if not structure.material in materials:
materials[structure.material] = i
return materials
@cached_property
def n_full(self):
m_full = _create_full_material_array(self.mesh, self.structures, self.materials)
n_full = np.ones_like(self.mesh.X_full)
for material, idx in self.materials.items():
n_full = np.where(m_full == idx, material(self.env), n_full)
return n_full.view(_array)
@property
def nx(self):
return self.n_full[1::2, ::2].view(_array)
@property
def ny(self):
return self.n_full[::2, 1::2].view(_array)
@property
def nz(self):
return self.n_full[::2, ::2].view(_array)
def _visualize(self, ax=None, n_cmap=None, cbar=True, show=True, **kwargs):
import matplotlib.pyplot as plt # fmt: skip
from matplotlib import colors # fmt: skip
from mpl_toolkits.axes_grid1 import make_axes_locatable # fmt: skip
debug_grid = kwargs.pop("debug_grid", False)
if n_cmap is None:
n_cmap = colors.LinearSegmentedColormap.from_list(
name="c_cmap", colors=["#ffffff", "#86b5dc"]
)
if ax is not None:
plt.sca(ax)
else:
ax = plt.gca()
n_full = np.real(self.n_full).copy()
n_full[0, 0] = 1.0
plt.pcolormesh(self.mesh.X_full, self.mesh.Y_full, n_full, cmap=n_cmap)
plt.axis("scaled")
if not debug_grid:
plt.grid(True)
else:
dx = self.mesh.dx
dy = self.mesh.dy
x_ticks = np.sort(np.unique(self.mesh.X_full.ravel()))[::2]
y_ticks = np.sort(np.unique(self.mesh.Y_full.ravel()))[::2]
plt.xticks(x_ticks - 0.25 * dx, [f"" for x in x_ticks - 0.25 * dx])
plt.yticks(y_ticks - 0.25 * dy, [f"" for y in y_ticks - 0.25 * dy])
plt.xticks(
x_ticks + 0.25 * dx, [f"" for x in x_ticks + 0.25 * dx], minor=True
)
plt.yticks(
y_ticks + 0.25 * dy, [f"" for y in y_ticks + 0.25 * dy], minor=True
)
plt.grid(True, which="major", ls="-")
plt.grid(True, which="minor", ls=":")
if cbar:
divider = make_axes_locatable(ax)
cax = divider.append_axes("right", size="5%", pad=0.05)
values = np.unique(self.n_full)
_cbar = plt.colorbar(ticks=values, cax=cax)
# material_names = ['air'] + [mat.name for mat in self.cell.materials]
# labels = [f"\n{n}\n{v:.3f}" for n, v in zip(material_names, values)]
labels = [f"{v:.3f}" for v in values]
_cbar.ax.set_yticklabels(labels, rotation=90, va="center", ha="center")
plt.sca(ax)
if show:
plt.show()
@property
def _cell(self) -> Optional[Cell]:
"""this is a hack. Don't use this property unless you know what you're doing."""
if "cell" in self._cache:
return self._cache["cell"]
else:
return None
