def __init__(self, alpha, order):
self.alpha = alpha
self.warp = WarpFactorCalculator(order)
cls = TriangleDiscretization
from pytools import wandering_element
from hedge.tools import normalize
vertices = [
cls.barycentric_to_equilateral(bary)
for bary in wandering_element(cls.dimensions + 1)
]
all_vertex_indices = range(cls.dimensions + 1)
face_vertex_indices = cls.geometry \
.face_vertices(all_vertex_indices)
faces_vertices = cls.geometry.face_vertices(vertices)
edgedirs = [normalize(v2 - v1) for v1, v2 in faces_vertices]
opp_vertex_indices = [
(set(all_vertex_indices) - set(fvi)).__iter__().next()
for fvi in face_vertex_indices
]
self.loop_info = zip(face_vertex_indices, edgedirs, opp_vertex_indices)
def __init__(self, alpha, order):
self.alpha = alpha
self.warp = WarpFactorCalculator(order)
cls = TriangleDiscretization
from pytools import wandering_element
from hedge.tools import normalize
vertices = [cls.barycentric_to_equilateral(bary)
for bary in wandering_element(cls.dimensions + 1)]
all_vertex_indices = range(cls.dimensions + 1)
face_vertex_indices = cls.geometry \
.face_vertices(all_vertex_indices)
faces_vertices = cls.geometry.face_vertices(vertices)
edgedirs = [normalize(v2 - v1) for v1, v2 in faces_vertices]
opp_vertex_indices = [
(set(all_vertex_indices) - set(fvi)).__iter__().next()
for fvi in face_vertex_indices]
self.loop_info = zip(
face_vertex_indices,
edgedirs,
opp_vertex_indices)
def equilateral_nodes(self):
"""Generate warped nodes in equilateral coordinates (x,y)."""
# port of Hesthaven/Warburton's Nodes3D routine
# Set optimized parameter alpha, depending on order N
alpha_opt = [
0, 0, 0, 0.1002, 1.1332, 1.5608, 1.3413, 1.2577, 1.1603, 1.10153,
0.6080, 0.4523, 0.8856, 0.8717, 0.9655
]
if self.order - 1 < len(alpha_opt):
alpha = alpha_opt[self.order - 1]
else:
alpha = 1
from pytools import wandering_element
vertices = [
self.barycentric_to_equilateral(bary)
for bary in wandering_element(self.dimensions + 1)
]
all_vertex_indices = range(self.dimensions + 1)
face_vertex_indices = self.geometry \
.face_vertices(all_vertex_indices)
faces_vertices = self.geometry \
.face_vertices(vertices)
bary_points = list(self.equidistant_barycentric_nodes())
equi_points = [
self.barycentric_to_equilateral(bp) for bp in bary_points
]
from hedge.tools import normalize
from operator import add, mul
tri_warp = TriangleWarper(alpha, self.order)
for fvi, (v1, v2, v3) in zip(face_vertex_indices, faces_vertices):
# find directions spanning the face: "base" and "altitude"
directions = [normalize(v2 - v1), normalize((v3) - (v1 + v2) / 2)]
# the two should be orthogonal
assert abs(numpy.dot(directions[0], directions[1])) < 1e-16
# find the vertex opposite to the current face
opp_vertex_index = (set(all_vertex_indices) -
set(fvi)).__iter__().next()
shifted = []
for bp, ep in zip(bary_points, equi_points):
face_bp = [bp[i] for i in fvi]
blend = reduce(mul,
face_bp) * (1 + alpha * bp[opp_vertex_index])**2
for i in fvi:
denom = bp[i] + 0.5 * bp[opp_vertex_index]
if abs(denom) > 1e-12:
blend /= denom
else:
blend = 0.5 # each edge gets shifted twice
break
shifted.append(ep + blend * reduce(add, (
tw * dir
for tw, dir in zip(tri_warp(face_bp), directions))))
equi_points = shifted
return equi_points
def equilateral_nodes(self):
"""Generate warped nodes in equilateral coordinates (x,y)."""
# port of Hesthaven/Warburton's Nodes3D routine
# Set optimized parameter alpha, depending on order N
alpha_opt = [0, 0, 0, 0.1002, 1.1332, 1.5608, 1.3413, 1.2577, 1.1603,
1.10153, 0.6080, 0.4523, 0.8856, 0.8717, 0.9655]
if self.order-1 < len(alpha_opt):
alpha = alpha_opt[self.order-1]
else:
alpha = 1
from pytools import wandering_element
vertices = [self.barycentric_to_equilateral(bary)
for bary in wandering_element(self.dimensions + 1)]
all_vertex_indices = range(self.dimensions + 1)
face_vertex_indices = self.geometry \
.face_vertices(all_vertex_indices)
faces_vertices = self.geometry \
.face_vertices(vertices)
bary_points = list(self.equidistant_barycentric_nodes())
equi_points = [self.barycentric_to_equilateral(bp)
for bp in bary_points]
from hedge.tools import normalize
from operator import add, mul
tri_warp = TriangleWarper(alpha, self.order)
for fvi, (v1, v2, v3) in zip(face_vertex_indices, faces_vertices):
# find directions spanning the face: "base" and "altitude"
directions = [normalize(v2 - v1), normalize((v3)-(v1+v2)/2)]
# the two should be orthogonal
assert abs(numpy.dot(directions[0], directions[1])) < 1e-16
# find the vertex opposite to the current face
opp_vertex_index = (
set(all_vertex_indices)
- set(fvi)).__iter__().next()
shifted = []
for bp, ep in zip(bary_points, equi_points):
face_bp = [bp[i] for i in fvi]
blend = reduce(mul, face_bp) * (1+alpha*bp[opp_vertex_index])**2
for i in fvi:
denom = bp[i] + 0.5*bp[opp_vertex_index]
if abs(denom) > 1e-12:
blend /= denom
else:
blend = 0.5 # each edge gets shifted twice
break
shifted.append(ep + blend*reduce(add,
(tw*dir for tw, dir in zip(tri_warp(face_bp), directions))))
equi_points = shifted
return equi_points
