/
createshells.py
78 lines (56 loc) · 2.9 KB
/
createshells.py
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
# Copyright (C) 2015-2018 Simon Biggs
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
# http://www.apache.org/licenses/LICENSE-2.0
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.
from pymedphys._imports import numpy as np
def calculate_coordinates_shell(distance, num_dimensions, distance_step_size):
"""Create the shell of coordinate shifts for the given testing distance.
Coordinate shifts are determined to check the evaluation dose for a
given distance, dimension, and step size
"""
if num_dimensions == 1:
return calculate_coordinates_shell_1d(distance)
if num_dimensions == 2:
return calculate_coordinates_shell_2d(distance, distance_step_size)
if num_dimensions == 3:
return calculate_coordinates_shell_3d(distance, distance_step_size)
raise ValueError("No valid dimension")
def calculate_coordinates_shell_1d(distance):
"""Output the two points that are of the defined distance in one-dimension"""
if distance == 0:
x_coords = np.array([0])
else:
x_coords = np.array([distance, -distance])
return (x_coords,)
def calculate_coordinates_shell_2d(distance, distance_step_size):
"""Create points along the circumference of a circle. The spacing
between points is not larger than the defined distance_step_size
"""
amount_to_check = np.ceil(2 * np.pi * distance / distance_step_size).astype(int) + 1
theta = np.linspace(0, 2 * np.pi, amount_to_check + 1)[:-1:]
x_coords = distance * np.cos(theta)
y_coords = distance * np.sin(theta)
return (x_coords, y_coords)
def calculate_coordinates_shell_3d(distance, distance_step_size):
"""Create points along the surface of a sphere (a shell) where no gap
between points is larger than the defined distance_step_size"""
number_of_rows = np.ceil(np.pi * distance / distance_step_size).astype(int) + 1
elevation = np.linspace(0, np.pi, number_of_rows)
row_radii = distance * np.sin(elevation)
row_circumference = 2 * np.pi * row_radii
amount_in_row = np.ceil(row_circumference / distance_step_size).astype(int) + 1
x_coords = []
y_coords = []
z_coords = []
for i, phi in enumerate(elevation):
azimuth = np.linspace(0, 2 * np.pi, amount_in_row[i] + 1)[:-1:]
x_coords.append(distance * np.sin(phi) * np.cos(azimuth))
y_coords.append(distance * np.sin(phi) * np.sin(azimuth))
z_coords.append(distance * np.cos(phi) * np.ones_like(azimuth))
return (np.hstack(x_coords), np.hstack(y_coords), np.hstack(z_coords))