1 | #!/usr/bin/env python |
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2 | """ |
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3 | Asymmetric shape integration |
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4 | |
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5 | Usage: |
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6 | |
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7 | explore/asymint.py [MODEL] [q-value] |
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8 | |
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9 | Computes the numerical integral over theta and phi of the given model at a |
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10 | single point q using different algorithms or the same algorithm with different |
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11 | precision. It also displays a 2-D image of the theta-phi surface that is |
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12 | being integrated. |
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13 | |
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14 | The available models are: |
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15 | |
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16 | triaxial_ellipsoid, parallelpiped, paracrystal, cylinder, sphere |
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17 | |
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18 | Cylinder and sphere are included as simple checks on the integration |
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19 | algorithms. Cylinder is better investigated using 1-D integration methods in |
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20 | explore/symint.py. Sphere has an easily computed analytic value which is |
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21 | identical for all theta-phi for a given q, so it is useful for checking |
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22 | that the normalization constants are correct for the different algorithms. |
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23 | """ |
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24 | |
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25 | from __future__ import print_function, division |
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26 | |
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27 | import os, sys |
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28 | sys.path.insert(0, os.path.dirname(os.path.dirname(os.path.realpath(__file__)))) |
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29 | import warnings |
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30 | |
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31 | import numpy as np |
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32 | import mpmath as mp |
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33 | from numpy import pi, sin, cos, sqrt, exp, expm1, degrees, log10, arccos |
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34 | from numpy.polynomial.legendre import leggauss |
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35 | from scipy.integrate import dblquad, simps, romb, romberg |
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36 | import pylab |
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37 | |
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38 | import sasmodels.special as sp |
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39 | |
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40 | DTYPE = 'd' |
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41 | |
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42 | class MPenv: |
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43 | sqrt = staticmethod(mp.sqrt) |
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44 | exp = staticmethod(mp.exp) |
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45 | expm1 = staticmethod(mp.expm1) |
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46 | cos = staticmethod(mp.cos) |
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47 | sin = staticmethod(mp.sin) |
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48 | tan = staticmethod(mp.tan) |
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49 | @staticmethod |
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50 | def sas_3j1x_x(x): |
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51 | return 3*(mp.sin(x)/x - mp.cos(x))/(x*x) |
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52 | @staticmethod |
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53 | def sas_2J1x_x(x): |
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54 | return 2*mp.j1(x)/x |
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55 | @staticmethod |
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56 | def sas_sinx_x(x): |
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57 | return mp.sin(x)/x |
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58 | pi = mp.pi |
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59 | mpf = staticmethod(mp.mpf) |
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60 | |
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61 | class NPenv: |
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62 | sqrt = staticmethod(np.sqrt) |
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63 | exp = staticmethod(np.exp) |
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64 | expm1 = staticmethod(np.expm1) |
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65 | cos = staticmethod(np.cos) |
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66 | sin = staticmethod(np.sin) |
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67 | tan = staticmethod(np.tan) |
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68 | sas_3j1x_x = staticmethod(sp.sas_3j1x_x) |
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69 | sas_2J1x_x = staticmethod(sp.sas_2J1x_x) |
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70 | sas_sinx_x = staticmethod(sp.sas_sinx_x) |
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71 | pi = np.pi |
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72 | #mpf = staticmethod(float) |
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73 | mpf = staticmethod(lambda x: np.array(x, DTYPE)) |
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74 | |
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75 | SLD = 3 |
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76 | SLD_SOLVENT = 6 |
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77 | CONTRAST = SLD - SLD_SOLVENT |
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78 | |
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79 | # Carefully code models so that mpmath will use full precision. That means: |
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80 | # * wrap inputs in env.mpf |
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81 | # * don't use floating point constants, only integers |
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82 | # * for division, make sure the numerator or denominator is env.mpf |
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83 | # * use env.pi, env.sas_sinx_x, etc. for functions |
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84 | def make_parallelepiped(a, b, c, env=NPenv): |
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85 | a, b, c = env.mpf(a), env.mpf(b), env.mpf(c) |
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86 | def Fq(qa, qb, qc): |
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87 | siA = env.sas_sinx_x(a*qa/2) |
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88 | siB = env.sas_sinx_x(b*qb/2) |
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89 | siC = env.sas_sinx_x(c*qc/2) |
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90 | return siA * siB * siC |
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91 | Fq.__doc__ = "parallelepiped a=%g, b=%g c=%g"%(a, b, c) |
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92 | volume = a*b*c |
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93 | norm = CONTRAST**2*volume/10000 |
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94 | return norm, Fq |
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95 | |
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96 | def make_core_shell_parallelepiped(a, b, c, da, db, dc, slda, sldb, sldc, env=NPenv): |
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97 | overlapping = False |
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98 | a, b, c = env.mpf(a), env.mpf(b), env.mpf(c) |
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99 | da, db, dc = env.mpf(da), env.mpf(db), env.mpf(dc) |
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100 | slda, sldb, sldc = env.mpf(slda), env.mpf(sldb), env.mpf(sldc) |
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101 | dr0 = CONTRAST |
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102 | drA, drB, drC = slda-SLD_SOLVENT, sldb-SLD_SOLVENT, sldc-SLD_SOLVENT |
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103 | tA, tB, tC = a + 2*da, b + 2*db, c + 2*dc |
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104 | def Fq(qa, qb, qc): |
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105 | siA = a*env.sas_sinx_x(a*qa/2) |
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106 | siB = b*env.sas_sinx_x(b*qb/2) |
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107 | siC = c*env.sas_sinx_x(c*qc/2) |
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108 | siAt = tA*env.sas_sinx_x(tA*qa/2) |
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109 | siBt = tB*env.sas_sinx_x(tB*qb/2) |
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110 | siCt = tC*env.sas_sinx_x(tC*qc/2) |
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111 | if overlapping: |
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112 | return (dr0*siA*siB*siC |
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113 | + drA*(siAt-siA)*siB*siC |
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114 | + drB*siAt*(siBt-siB)*siC |
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115 | + drC*siAt*siBt*(siCt-siC)) |
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116 | else: |
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117 | return (dr0*siA*siB*siC |
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118 | + drA*(siAt-siA)*siB*siC |
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119 | + drB*siA*(siBt-siB)*siC |
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120 | + drC*siA*siB*(siCt-siC)) |
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121 | Fq.__doc__ = "core-shell parallelepiped a=%g, b=%g c=%g"%(a, b, c) |
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122 | if overlapping: |
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123 | volume = a*b*c + 2*da*b*c + 2*tA*db*c + 2*tA*tB*dc |
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124 | else: |
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125 | volume = a*b*c + 2*da*b*c + 2*a*db*c + 2*a*b*dc |
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126 | norm = 1/(volume*10000) |
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127 | return norm, Fq |
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128 | |
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129 | def make_triaxial_ellipsoid(a, b, c, env=NPenv): |
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130 | a, b, c = env.mpf(a), env.mpf(b), env.mpf(c) |
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131 | def Fq(qa, qb, qc): |
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132 | qr = env.sqrt((a*qa)**2 + (b*qb)**2 + (c*qc)**2) |
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133 | return env.sas_3j1x_x(qr) |
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134 | Fq.__doc__ = "triaxial ellipsoid minor=%g, major=%g polar=%g"%(a, b, c) |
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135 | volume = 4*env.pi*a*b*c/3 |
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136 | norm = CONTRAST**2*volume/10000 |
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137 | return norm, Fq |
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138 | |
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139 | def make_cylinder(radius, length, env=NPenv): |
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140 | radius, length = env.mpf(radius), env.mpf(length) |
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141 | def Fq(qa, qb, qc): |
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142 | qab = env.sqrt(qa**2 + qb**2) |
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143 | return env.sas_2J1x_x(qab*radius) * env.sas_sinx_x((qc*length)/2) |
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144 | Fq.__doc__ = "cylinder radius=%g, length=%g"%(radius, length) |
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145 | volume = env.pi*radius**2*length |
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146 | norm = CONTRAST**2*volume/10000 |
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147 | return norm, Fq |
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148 | |
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149 | def make_sphere(radius, env=NPenv): |
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150 | radius = env.mpf(radius) |
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151 | def Fq(qa, qb, qc): |
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152 | q = env.sqrt(qa**2 + qb**2 + qc**2) |
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153 | return env.sas_3j1x_x(q*radius) |
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154 | Fq.__doc__ = "sphere radius=%g"%(radius, ) |
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155 | volume = 4*pi*radius**3 |
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156 | norm = CONTRAST**2*volume/10000 |
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157 | return norm, Fq |
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158 | |
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159 | def make_paracrystal(radius, dnn, d_factor, lattice='bcc', env=NPenv): |
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160 | radius, dnn, d_factor = env.mpf(radius), env.mpf(dnn), env.mpf(d_factor) |
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161 | def sc(qa, qb, qc): |
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162 | return qa, qb, qc |
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163 | def bcc(qa, qb, qc): |
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164 | a1 = (+qa + qb + qc)/2 |
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165 | a2 = (-qa - qb + qc)/2 |
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166 | a3 = (-qa + qb - qc)/2 |
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167 | return a1, a2, a3 |
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168 | def fcc(qa, qb, qc): |
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169 | a1 = ( 0 + qb + qc)/2 |
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170 | a2 = (-qa + 0 + qc)/2 |
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171 | a3 = (-qa + qb + 0)/2 |
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172 | return a1, a2, a3 |
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173 | lattice_fn = {'sc': sc, 'bcc': bcc, 'fcc': fcc}[lattice] |
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174 | radius, dnn, d_factor = env.mpf(radius), env.mpf(dnn), env.mpf(d_factor) |
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175 | def Fq(qa, qb, qc): |
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176 | a1, a2, a3 = lattice_fn(qa, qb, qc) |
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177 | # Note: paper says that different directions can have different |
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178 | # distoration factors. Easy enough to add to the code. |
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179 | arg = -(dnn*d_factor)**2*(a1**2 + a2**2 + a3**2)/2 |
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180 | exp_arg = env.exp(arg) |
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181 | den = [((exp_arg - 2*env.cos(dnn*a))*exp_arg + 1) for a in (a1, a2, a3)] |
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182 | Sq = -env.expm1(2*arg)**3/(den[0]*den[1]*den[2]) |
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183 | |
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184 | q = env.sqrt(qa**2 + qb**2 + qc**2) |
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185 | Fq = env.sas_3j1x_x(q*radius) |
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186 | # the caller computes F(q)**2, but we need it to compute S(q)*F(q)**2 |
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187 | return env.sqrt(Sq)*Fq |
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188 | Fq.__doc__ = "%s paracrystal a=%g da=%g r=%g"%(lattice, dnn, d_factor, radius) |
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189 | def sphere_volume(r): return 4*env.pi*r**3/3 |
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190 | Vf = { |
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191 | 'sc': sphere_volume(radius/dnn), |
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192 | 'bcc': 2*sphere_volume(env.sqrt(3)/2*radius/dnn), |
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193 | 'fcc': 4*sphere_volume(1/env.sqrt(2)*radius/dnn), |
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194 | }[lattice] |
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195 | volume = sphere_volume(radius) |
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196 | norm = CONTRAST**2*volume/10000*Vf |
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197 | return norm, Fq |
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198 | |
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199 | NORM = 1.0 # type: float |
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200 | KERNEL = None # type: CALLABLE[[ndarray, ndarray, ndarray], ndarray] |
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201 | NORM_MP = 1 # type: mpf |
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202 | KERNEL = None # type: CALLABLE[[mpf, mpf, mpf], mpf] |
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203 | |
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204 | SHAPES = [ |
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205 | 'sphere', |
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206 | 'cylinder', |
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207 | 'triaxial_ellipsoid', |
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208 | 'parallelepiped', |
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209 | 'core_shell_parallelepiped', |
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210 | 'fcc_paracrystal', |
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211 | 'bcc_paracrystal', |
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212 | 'sc_paracrystal', |
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213 | ] |
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214 | def build_shape(shape, **pars): |
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215 | global NORM, KERNEL |
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216 | global NORM_MP, KERNEL_MP |
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217 | |
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218 | # Note: using integer or string defaults for the sake of mpf |
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219 | if shape == 'sphere': |
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220 | RADIUS = pars.get('radius', 50) |
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221 | NORM, KERNEL = make_sphere(radius=RADIUS) |
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222 | NORM_MP, KERNEL_MP = make_sphere(radius=RADIUS, env=MPenv) |
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223 | elif shape == 'cylinder': |
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224 | #RADIUS, LENGTH = 10, 100000 |
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225 | RADIUS = pars.get('radius', 10) |
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226 | LENGTH = pars.get('radius', 300) |
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227 | NORM, KERNEL = make_cylinder(radius=RADIUS, length=LENGTH) |
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228 | NORM_MP, KERNEL_MP = make_cylinder(radius=RADIUS, length=LENGTH, env=MPenv) |
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229 | elif shape == 'triaxial_ellipsoid': |
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230 | #A, B, C = 4450, 14000, 47 |
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231 | A = pars.get('a', 445) |
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232 | B = pars.get('b', 140) |
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233 | C = pars.get('c', 47) |
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234 | NORM, KERNEL = make_triaxial_ellipsoid(A, B, C) |
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235 | NORM_MP, KERNEL_MP = make_triaxial_ellipsoid(A, B, C, env=MPenv) |
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236 | elif shape == 'parallelepiped': |
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237 | #A, B, C = 4450, 14000, 47 |
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238 | A = pars.get('a', 445) |
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239 | B = pars.get('b', 140) |
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240 | C = pars.get('c', 47) |
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241 | NORM, KERNEL = make_parallelepiped(A, B, C) |
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242 | NORM_MP, KERNEL_MP = make_parallelepiped(A, B, C, env=MPenv) |
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243 | elif shape == 'core_shell_parallelepiped': |
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244 | #A, B, C = 4450, 14000, 47 |
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245 | #A, B, C = 445, 140, 47 # integer for the sake of mpf |
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246 | A = pars.get('a', 114) |
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247 | B = pars.get('b', 1380) |
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248 | C = pars.get('c', 6800) |
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249 | DA = pars.get('da', 21) |
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250 | DB = pars.get('db', 58) |
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251 | DC = pars.get('dc', 2300) |
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252 | SLDA = pars.get('slda', "5") |
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253 | SLDB = pars.get('sldb', "-0.3") |
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254 | SLDC = pars.get('sldc', "11.5") |
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255 | ## default parameters from sasmodels |
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256 | #A,B,C,DA,DB,DC,SLDA,SLDB,SLDC = 400,75,35,10,10,10,2,4,2 |
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257 | ## swap A-B-C to C-B-A |
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258 | #A, B, C, DA, DB, DC, SLDA, SLDB, SLDC = C, B, A, DC, DB, DA, SLDC, SLDB, SLDA |
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259 | #A,B,C,DA,DB,DC,SLDA,SLDB,SLDC = 10,20,30,100,200,300,1,2,3 |
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260 | #SLD_SOLVENT,CONTRAST = 0, 4 |
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261 | if 1: # C shortest |
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262 | B, C = C, B |
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263 | DB, DC = DC, DB |
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264 | SLDB, SLDC = SLDC, SLDB |
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265 | elif 0: # C longest |
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266 | A, C = C, A |
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267 | DA, DC = DC, DA |
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268 | SLDA, SLDC = SLDC, SLDA |
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269 | #NORM, KERNEL = make_core_shell_parallelepiped(A, B, C, DA, DB, DC, SLDA, SLDB, SLDC) |
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270 | NORM, KERNEL = make_core_shell_parallelepiped(A, B, C, DA, DB, DC, SLDA, SLDB, SLDC) |
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271 | NORM_MP, KERNEL_MP = make_core_shell_parallelepiped(A, B, C, DA, DB, DC, SLDA, SLDB, SLDC, env=MPenv) |
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272 | elif shape.endswith('paracrystal'): |
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273 | LATTICE, _ = shape.split('_') |
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274 | DNN = pars.get('dnn', 220) |
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275 | D_FACTOR = pars.get('d_factor', '0.06') |
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276 | RADIUS = pars.get('radius', 40) |
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277 | NORM, KERNEL = make_paracrystal( |
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278 | radius=RADIUS, dnn=DNN, d_factor=D_FACTOR, lattice=LATTICE) |
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279 | NORM_MP, KERNEL_MP = make_paracrystal( |
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280 | radius=RADIUS, dnn=DNN, d_factor=D_FACTOR, lattice=LATTICE, env=MPenv) |
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281 | else: |
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282 | raise ValueError("Unknown shape %r"%shape) |
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283 | |
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284 | # Note: hardcoded in mp_quad |
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285 | THETA_LOW, THETA_HIGH = 0, pi |
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286 | PHI_LOW, PHI_HIGH = 0, 2*pi |
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287 | SCALE = 1 |
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288 | |
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289 | # mathematica code for triaxial_ellipsoid (untested) |
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290 | _ = """ |
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291 | R[theta_, phi_, a_, b_, c_] := Sqrt[(a Sin[theta]Cos[phi])^2 + (b Sin[theta]Sin[phi])^2 + (c Cos[theta])^2] |
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292 | Sphere[q_, r_] := 3 SphericalBesselJ[q r]/(q r) |
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293 | V[a_, b_, c_] := 4/3 pi a b c |
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294 | Norm[sld_, solvent_, a_, b_, c_] := V[a, b, c] (solvent - sld)^2 |
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295 | F[q_, theta_, phi_, a_, b_, c_] := Sphere[q, R[theta, phi, a, b, c]] |
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296 | I[q_, sld_, solvent_, a_, b_, c_] := Norm[sld, solvent, a, b, c]/(4 pi) Integrate[F[q, theta, phi, a, b, c]^2 Sin[theta], {phi, 0, 2 pi}, {theta, 0, pi}] |
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297 | I[6/10^3, 63/10, 3, 445, 140, 47] |
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298 | """ |
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299 | |
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300 | # 2D integration functions |
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301 | def mp_quad_2d(q): |
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302 | evals = [0] |
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303 | def integrand(theta, phi): |
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304 | evals[0] += 1 |
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305 | qab = q*mp.sin(theta) |
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306 | qa = qab*mp.cos(phi) |
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307 | qb = qab*mp.sin(phi) |
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308 | qc = q*mp.cos(theta) |
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309 | Zq = KERNEL_MP(qa, qb, qc)**2 |
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310 | return Zq*mp.sin(theta) |
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311 | ans = mp.quad(integrand, (0, mp.pi), (0, 2*mp.pi)) |
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312 | Iq = NORM_MP*ans/(4*mp.pi) |
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313 | return evals[0], Iq |
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314 | |
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315 | def kernel_2d(q, theta, phi): |
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316 | """ |
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317 | S(q) kernel for paracrystal forms. |
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318 | """ |
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319 | qab = q*sin(theta) |
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320 | qa = qab*cos(phi) |
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321 | qb = qab*sin(phi) |
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322 | qc = q*cos(theta) |
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323 | return NORM*KERNEL(qa, qb, qc)**2 |
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324 | |
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325 | def scipy_dblquad_2d(q): |
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326 | """ |
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327 | Compute the integral using scipy dblquad. This gets the correct answer |
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328 | eventually, but it is slow. |
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329 | """ |
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330 | evals = [0] |
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331 | def integrand(phi, theta): |
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332 | evals[0] += 1 |
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333 | Zq = kernel_2d(q, theta=theta, phi=phi) |
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334 | return Zq*sin(theta) |
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335 | ans = dblquad(integrand, THETA_LOW, THETA_HIGH, lambda x: PHI_LOW, lambda x: PHI_HIGH)[0] |
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336 | return evals[0], ans*SCALE/(4*pi) |
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337 | |
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338 | |
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339 | def scipy_romberg_2d(q): |
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340 | """ |
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341 | Compute the integral using romberg integration. This function does not |
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342 | complete in a reasonable time. No idea if it is accurate. |
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343 | """ |
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344 | evals = [0] |
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345 | def inner(phi, theta): |
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346 | evals[0] += 1 |
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347 | return kernel_2d(q, theta=theta, phi=phi) |
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348 | def outer(theta): |
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349 | Zq = romberg(inner, PHI_LOW, PHI_HIGH, divmax=100, args=(theta,)) |
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350 | return Zq*sin(theta) |
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351 | ans = romberg(outer, THETA_LOW, THETA_HIGH, divmax=100) |
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352 | return evals[0], ans*SCALE/(4*pi) |
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353 | |
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354 | |
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355 | def semi_romberg_2d(q, n=100): |
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356 | """ |
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357 | Use 1D romberg integration in phi and regular simpsons rule in theta. |
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358 | """ |
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359 | evals = [0] |
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360 | def inner(phi, theta): |
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361 | evals[0] += 1 |
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362 | return kernel_2d(q, theta=theta, phi=phi) |
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363 | theta = np.linspace(THETA_LOW, THETA_HIGH, n) |
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364 | Zq = [romberg(inner, PHI_LOW, PHI_HIGH, divmax=100, args=(t,)) for t in theta] |
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365 | ans = simps(np.array(Zq)*sin(theta), dx=theta[1]-theta[0]) |
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366 | return evals[0], ans*SCALE/(4*pi) |
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367 | |
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368 | def gauss_quad_2d(q, n=150): |
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369 | """ |
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370 | Compute the integral using gaussian quadrature for n = 20, 76 or 150. |
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371 | """ |
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372 | z, w = leggauss(n) |
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373 | theta = (THETA_HIGH-THETA_LOW)*(z + 1)/2 + THETA_LOW |
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374 | phi = (PHI_HIGH-PHI_LOW)*(z + 1)/2 + PHI_LOW |
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375 | Atheta, Aphi = np.meshgrid(theta, phi) |
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376 | Aw = w[None, :] * w[:, None] |
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377 | sin_theta = abs(sin(Atheta)) |
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378 | Zq = kernel_2d(q=q, theta=Atheta, phi=Aphi) |
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379 | # change from [-1,1] x [-1,1] range to [0, pi] x [0, 2 pi] range |
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380 | dxdy_stretch = (THETA_HIGH-THETA_LOW)/2 * (PHI_HIGH-PHI_LOW)/2 |
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381 | Iq = np.sum(Zq*Aw*sin_theta)*SCALE/(4*pi) * dxdy_stretch |
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382 | return n**2, Iq |
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383 | |
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384 | def gauss_quad_usub(q, n=150, dtype=DTYPE): |
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385 | """ |
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386 | Compute the integral using gaussian quadrature for n = 20, 76 or 150. |
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387 | |
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388 | Use *u = sin theta* substitution, and restrict integration over a single |
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389 | quadrant for shapes that are mirror symmetric about AB, AC and BC planes. |
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390 | |
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391 | Note that this doesn't work for fcc/bcc paracrystals, which instead step |
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392 | over the entire 4 pi surface uniformly in theta-phi. |
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393 | """ |
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394 | z, w = leggauss(n) |
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395 | cos_theta = 0.5 * (z + 1) |
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396 | theta = arccos(cos_theta) |
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397 | phi = pi/2*(0.5 * (z + 1)) |
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398 | Atheta, Aphi = np.meshgrid(theta, phi) |
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399 | Aw = w[None, :] * w[:, None] |
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400 | q, Atheta, Aphi, Aw = [np.asarray(v, dtype=dtype) for v in (q, Atheta, Aphi, Aw)] |
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401 | Zq = kernel_2d(q=q, theta=Atheta, phi=Aphi) |
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402 | Iq = np.sum(Zq*Aw)*0.25 |
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403 | return n**2, Iq |
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404 | |
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405 | def gridded_2d(q, n=300): |
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406 | """ |
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407 | Compute the integral on a regular grid using rectangular, trapezoidal, |
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408 | simpsons, and romberg integration. Romberg integration requires that |
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409 | the grid be of size n = 2**k + 1. |
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410 | """ |
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411 | theta = np.linspace(THETA_LOW, THETA_HIGH, n) |
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412 | phi = np.linspace(PHI_LOW, PHI_HIGH, n) |
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413 | Atheta, Aphi = np.meshgrid(theta, phi) |
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414 | Zq = kernel_2d(q=q, theta=Atheta, phi=Aphi) |
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415 | Zq *= abs(sin(Atheta)) |
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416 | dx, dy = theta[1]-theta[0], phi[1]-phi[0] |
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417 | print("rect-%d"%n, n**2, np.sum(Zq)*dx*dy*SCALE/(4*pi)) |
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418 | print("trapz-%d"%n, n**2, np.trapz(np.trapz(Zq, dx=dx), dx=dy)*SCALE/(4*pi)) |
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419 | print("simpson-%d"%n, n**2, simps(simps(Zq, dx=dx), dx=dy)*SCALE/(4*pi)) |
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420 | print("romb-%d"%n, n**2, romb(romb(Zq, dx=dx), dx=dy)*SCALE/(4*pi)) |
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421 | |
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422 | def quadpy_method(q, rule): |
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423 | """ |
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424 | Use *rule*="name:index" where name and index are chosen from below. |
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425 | |
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426 | Available rule names and the corresponding indices:: |
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427 | |
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428 | AlbrechtCollatz: [1-5] |
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429 | BazantOh: 9, 11, 13 |
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430 | HeoXu: 13, 15, 17, 19-[1-2], 21-[1-6], 23-[1-3], 25-[1-2], 27-[1-3], |
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431 | 29, 31, 33, 35, 37, 39-[1-2] |
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432 | FliegeMaier: 4, 9, 16, 25 |
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433 | Lebedev: 3[a-c], 5, 7, 9, 11, 13, 15, 17, 19, 21, 23, 25, 27, 29, 31, 35, |
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434 | 41, 47, 53, 59, 65, 71, 77 83, 89, 95, 101, 107, 113, 119, 125, 131 |
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435 | McLaren: [1-10] |
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436 | Stroud: U3 3-1, U3 5-[1-5], U3 7-[1-2], U3 8-1, U3 9-[1-3], |
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437 | U3 11-[1-3], U3 14-1 |
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438 | """ |
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439 | try: |
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440 | import quadpy |
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441 | except ImportError: |
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442 | warnings.warn("use 'pip install quadpy' to enable quadpy.sphere tests") |
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443 | return |
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444 | |
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445 | from quadpy.sphere import (AlbrechtCollatz, BazantOh, HeoXu, |
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446 | FliegeMaier, Lebedev, McLaren, Stroud, integrate_spherical) |
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447 | RULES = { |
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448 | 'AlbrechtCollatz': AlbrechtCollatz, |
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449 | 'BazantOh': BazantOh, |
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450 | 'HeoXu': HeoXu, |
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451 | 'FliegeMaier': FliegeMaier, |
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452 | 'Lebedev': Lebedev, |
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453 | 'McLaren': McLaren, |
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454 | 'Stroud': Stroud, |
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455 | } |
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456 | int_index = 'AlbrechtCollatz', 'McLaren' |
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457 | |
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458 | rule_name, rule_index = rule.split(':') |
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459 | index = int(rule_index) if rule_name in int_index else rule_index |
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460 | rule_obj = RULES[rule_name](index) |
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461 | fn = lambda azimuthal, polar: kernel_2d(q=q, theta=polar, phi=azimuthal) |
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462 | Iq = integrate_spherical(fn, rule=rule_obj)/(4*pi) |
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463 | print("%s degree=%d points=%s => %.15g" |
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464 | % (rule, rule_obj.degree, len(rule_obj.points), Iq)) |
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465 | |
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466 | def plot_2d(q, n=300): |
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467 | """ |
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468 | Plot the 2D surface that needs to be integrated in order to compute |
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469 | the BCC S(q) at a particular q, dnn and d_factor. *n* is the number |
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470 | of points in the grid. |
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471 | """ |
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472 | theta = np.linspace(THETA_LOW, THETA_HIGH, n) |
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473 | phi = np.linspace(PHI_LOW, PHI_HIGH, n) |
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474 | Atheta, Aphi = np.meshgrid(theta, phi) |
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475 | Zq = kernel_2d(q=q, theta=Atheta, phi=Aphi) |
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476 | #Zq *= abs(sin(Atheta)) |
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477 | pylab.pcolor(degrees(theta), degrees(phi), log10(np.fmax(Zq, 1.e-6))) |
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478 | pylab.axis('tight') |
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479 | pylab.title("%s I(q,t) sin(t) for q=%g" % (KERNEL.__doc__, q)) |
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480 | pylab.xlabel("theta (degrees)") |
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481 | pylab.ylabel("phi (degrees)") |
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482 | cbar = pylab.colorbar() |
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483 | cbar.set_label('log10 S(q)') |
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484 | pylab.show() |
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485 | |
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486 | def main(): |
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487 | import argparse |
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488 | |
---|
489 | parser = argparse.ArgumentParser( |
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490 | description="asymmetric integration explorer", |
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491 | formatter_class=argparse.ArgumentDefaultsHelpFormatter, |
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492 | ) |
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493 | parser.add_argument('-s', '--shape', choices=SHAPES, |
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494 | default='parallelepiped', |
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495 | help='oriented shape') |
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496 | parser.add_argument('-q', '--q_value', type=str, default='0.005', |
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497 | help='Q value to evaluate') |
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498 | parser.add_argument('pars', type=str, nargs='*', default=[], |
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499 | help='p=val for p in shape parameters') |
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500 | opts = parser.parse_args() |
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501 | pars = {k: v for par in opts.pars for k, v in [par.split('=')]} |
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502 | build_shape(opts.shape, **pars) |
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503 | |
---|
504 | Q = float(opts.q_value) |
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505 | if opts.shape == 'sphere': |
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506 | print("exact", NORM*sp.sas_3j1x_x(Q*RADIUS)**2) |
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507 | |
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508 | # Methods from quadpy, if quadpy is available |
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509 | # AlbrechtCollatz: [1-5] |
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510 | # BazantOh: 9, 11, 13 |
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511 | # HeoXu: 13, 15, 17, 19-[1-2], 21-[1-6], 23-[1-3], 25-[1-2], 27-[1-3], |
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512 | # 29, 31, 33, 35, 37, 39-[1-2] |
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513 | # FliegeMaier: 4, 9, 16, 25 |
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514 | # Lebedev: 3[a-c], 5, 7, 9, 11, 13, 15, 17, 19, 21, 23, 25, 27, 29, 31, 35, |
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515 | # 41, 47, 53, 59, 65, 71, 77 83, 89, 95, 101, 107, 113, 119, 125, 131 |
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516 | # McLaren: [1-10] |
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517 | # Stroud: U3 3-1, U3 5-[1-5], U3 7-[1-2], U3 8-1, U3 9-[1-3], |
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518 | # U3 11-[1-3], U3 14-1 |
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519 | quadpy_method(Q, "AlbrechtCollatz:5") |
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520 | quadpy_method(Q, "HeoXu:39-2") |
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521 | quadpy_method(Q, "FliegeMaier:25") |
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522 | quadpy_method(Q, "Lebedev:19") |
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523 | quadpy_method(Q, "Lebedev:131") |
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524 | quadpy_method(Q, "McLaren:10") |
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525 | quadpy_method(Q, "Stroud:U3 14-1") |
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526 | |
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527 | print("gauss-20 points=%d => %.15g" % gauss_quad_2d(Q, n=20)) |
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528 | print("gauss-76 points=%d => %.15g" % gauss_quad_2d(Q, n=76)) |
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529 | print("gauss-150 points=%d => %.15g" % gauss_quad_2d(Q, n=150)) |
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530 | print("gauss-500 points=%d => %.15g" % gauss_quad_2d(Q, n=500)) |
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531 | print("gauss-1025 points=%d => %.15g" % gauss_quad_2d(Q, n=1025)) |
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532 | print("gauss-2049 points=%d => %.15g" % gauss_quad_2d(Q, n=2049)) |
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533 | print("gauss-20 usub points=%d => %.15g" % gauss_quad_usub(Q, n=20)) |
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534 | print("gauss-76 usub points=%d => %.15g" % gauss_quad_usub(Q, n=76)) |
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535 | print("gauss-150 usub points=%d => %.15g" % gauss_quad_usub(Q, n=150)) |
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536 | |
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537 | #gridded_2d(Q, n=2**8+1) |
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538 | gridded_2d(Q, n=2**10+1) |
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539 | #gridded_2d(Q, n=2**12+1) |
---|
540 | #gridded_2d(Q, n=2**15+1) |
---|
541 | # adaptive forms on models for which the calculations are fast enough |
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542 | SLOW_SHAPES = { |
---|
543 | 'fcc_paracrystal', 'bcc_paracrystal', 'sc_paracrystal', |
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544 | 'core_shell_parallelepiped', |
---|
545 | } |
---|
546 | if opts.shape not in SLOW_SHAPES: |
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547 | print("dblquad", *scipy_dblquad_2d(Q)) |
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548 | print("semi-romberg-100", *semi_romberg_2d(Q, n=100)) |
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549 | print("romberg", *scipy_romberg_2d(Q)) |
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550 | with mp.workprec(100): |
---|
551 | print("mpmath", *mp_quad_2d(mp.mpf(opts.q_value))) |
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552 | plot_2d(Q, n=200) |
---|
553 | |
---|
554 | if __name__ == "__main__": |
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555 | main() |
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