1 | /** |
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2 | This software was developed by Institut Laue-Langevin as part of |
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3 | Distributed Data Analysis of Neutron Scattering Experiments (DANSE). |
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4 | |
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5 | Copyright 2012 Institut Laue-Langevin |
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6 | |
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7 | **/ |
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8 | |
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9 | #include <math.h> |
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10 | #include "parameters.hh" |
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11 | #include "teubner_strey.h" |
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12 | |
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13 | TeubnerStreyModel::TeubnerStreyModel() { |
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14 | scale = Parameter(0.1); |
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15 | c1 = Parameter(-30.0); |
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16 | c2 = Parameter(5000.0); |
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17 | background = Parameter(0.0); |
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18 | } |
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19 | |
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20 | double TeubnerStreyModel::operator()(double q) { |
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21 | double d_scale = scale(); |
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22 | double d_c1 = c1(); |
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23 | double d_c2 = c2(); |
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24 | double d_background = background(); |
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25 | |
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26 | double term1 = d_c1 * pow(q,2); |
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27 | double term2 = d_c2 * pow(q,4); |
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28 | |
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29 | return 1/(d_scale + term1 + term2) + d_background; |
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30 | |
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31 | } |
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32 | |
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33 | |
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34 | double TeubnerStreyModel::operator()(double qx,double qy) { |
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35 | double q = sqrt(qx*qx + qy*qy); |
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36 | return this->operator()(q); |
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37 | } |
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38 | |
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39 | double TeubnerStreyModel::calculate_ER() { |
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40 | // not implemented yet |
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41 | return 0.0; |
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42 | } |
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43 | |
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44 | double TeubnerStreyModel::calculate_VR() { |
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45 | return 1.0; |
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46 | } |
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47 | |
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48 | double TeubnerStreyModel::evaluate_rphi(double q,double phi) { |
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49 | double qx = q*cos(phi); |
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50 | double qy = q*sin(phi); |
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51 | return this->operator()(qx, qy); |
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52 | } |
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53 | |
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54 | |
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55 | |
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56 | /*** |
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57 | Notes |
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58 | |
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59 | This file was ported from python to C++ at ILL Grenoble in |
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60 | July 2012. In the original python file were two functions, |
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61 | teubnerStreyLengths and teubnerStreyDistance that did not appear |
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62 | to be used anywhere in the code. The source for them is below: |
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63 | |
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64 | def teubnerStreyLengths(self): |
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65 | """ |
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66 | Calculate the correlation length (L) |
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67 | @return L: the correlation distance |
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68 | """ |
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69 | return math.pow( 1/2 * math.pow( (self.params['scale']/self.params['c2']), 1/2 )\ |
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70 | +(self.params['c1']/(4*self.params['c2'])),-1/2 ) |
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71 | def teubnerStreyDistance(self): |
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72 | """ |
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73 | Calculate the quasi-periodic repeat distance (D/(2*pi)) |
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74 | @return D: quasi-periodic repeat distance |
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75 | """ |
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76 | return math.pow( 1/2 * math.pow( (self.params['scale']/self.params['c2']), 1/2 )\ |
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77 | -(self.params['c1']/(4*self.params['c2'])),-1/2 ) |
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78 | |
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79 | |
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80 | ***/ |
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