source: sasview/src/sas/models/c_extension/c_models/surfacefractal.cpp @ 79492222

ESS_GUIESS_GUI_DocsESS_GUI_batch_fittingESS_GUI_bumps_abstractionESS_GUI_iss1116ESS_GUI_iss879ESS_GUI_iss959ESS_GUI_openclESS_GUI_orderingESS_GUI_sync_sascalccostrafo411magnetic_scattrelease-4.1.1release-4.1.2release-4.2.2release_4.0.1ticket-1009ticket-1094-headlessticket-1242-2d-resolutionticket-1243ticket-1249ticket885unittest-saveload
Last change on this file since 79492222 was 79492222, checked in by krzywon, 8 years ago

Changed the file and folder names to remove all SANS references.

  • Property mode set to 100644
File size: 3.1 KB
Line 
1/**
2        This software was developed by the University of Tennessee as part of the
3        Distributed Data Analysis of Neutron Scattering Experiments (DANSE)
4        project funded by the US National Science Foundation.
5
6        If you use DANSE applications to do scientific research that leads to
7        publication, we ask that you acknowledge the use of the software with the
8        following sentence:
9
10        "This work benefited from DANSE software developed under NSF award DMR-0520547."
11
12        copyright 2008, University of Tennessee
13 */
14
15/**
16 * Scattering model classes
17 * The classes use the IGOR library found in
18 *   sansmodels/src/libigor
19 *
20 */
21
22#include <math.h>
23#include "parameters.hh"
24#include <stdio.h>
25using namespace std;
26#include "surfacefractal.h"
27extern "C" {
28#include "libmultifunc/libfunc.h"
29}
30
31static double surface_fractal_kernel(double dp[], double q) {
32  //fit parameters
33  double scale = dp[0];
34  double radius = dp[1];
35  double surface_dim = dp[2];
36  double co_length = dp[3];
37  double background = dp[4];
38  //others
39  double pq = 0.0;
40  double sq = 0.0;
41  double mmo = 0.0;
42  //result
43  double result = 0.0;
44  if( (q*radius) == 0.0){
45                pq = 1.0;
46  }
47  else{
48        //calculate P(q) for the spherical subunits; not normalized
49        pq = pow((3.0*(sin(q*radius) - q*radius*cos(q*radius))/pow((q*radius),3)),2);
50  }
51  mmo = 5.0 - surface_dim;
52
53  //calculate S(q)
54  sq = exp(gamln(mmo))*sin(-(mmo)*atan(q*co_length));
55  sq *= pow(co_length, mmo);
56  sq /= pow((1.0 + (q*co_length)*(q*co_length)),(mmo/2.0));
57  sq /= q;
58  //combine and return
59  result = pq * sq;
60  result *= scale;
61  result += background;
62
63  return(result);
64}
65
66SurfaceFractalModel :: SurfaceFractalModel() {
67  scale      = Parameter(1.0);
68  radius = Parameter(10.0);
69  surface_dim = Parameter(2.0);
70  co_length = Parameter(500.0);
71  background = Parameter(0.0);
72}
73
74/**
75 * Function to evaluate 1D scattering function
76 * @param q: q-value
77 * @return: function value
78 */
79double SurfaceFractalModel :: operator()(double q) {
80  double dp[5];
81
82  // Add the background after averaging
83  dp[0] = scale();
84  dp[1] = radius();
85  dp[2] = surface_dim();
86  dp[3] = co_length();
87  dp[4] = 0.0;
88
89  // Perform the computation
90  double sum = 0.0;
91
92  sum = surface_fractal_kernel(dp, fabs(q));
93  return sum + background();
94}
95
96/**
97 * Function to evaluate 2D scattering function
98 * @param q_x: value of Q along x
99 * @param q_y: value of Q along y
100 * @return: function value
101 */
102double SurfaceFractalModel :: operator()(double qx, double qy) {
103  double q = sqrt(qx*qx + qy*qy);
104  return (*this).operator()(q);
105}
106
107/**
108 * Function to evaluate 2D scattering function
109 * @param pars: parameters of the SurfaceFractalModel
110 * @param q: q-value
111 * @param phi: angle phi
112 * @return: function value
113 */
114double SurfaceFractalModel :: evaluate_rphi(double q, double phi) {
115  return (*this).operator()(q);
116}
117
118/**
119 * Function to calculate effective radius
120 * @return: effective radius value
121 */
122double SurfaceFractalModel :: calculate_ER() {
123  //NOT implemented yet!!! 'cause None shape Model
124  return 0.0;
125}
126double SurfaceFractalModel :: calculate_VR() {
127  return 1.0;
128}
Note: See TracBrowser for help on using the repository browser.