Changeset 8dc02d8b in sasview for sansmodels/src/sans/models/c_models/parameters.cpp

Timestamp:

Jan 20, 2011 2:10:08 PM (13 years ago)

Author:

Jae Cho <jhjcho@…>

Branches:

master, ESS_GUI, ESS_GUI_Docs, ESS_GUI_batch_fitting, ESS_GUI_bumps_abstraction, ESS_GUI_iss1116, ESS_GUI_iss879, ESS_GUI_iss959, ESS_GUI_opencl, ESS_GUI_ordering, ESS_GUI_sync_sascalc, costrafo411, magnetic_scatt, release-4.1.1, release-4.1.2, release-4.2.2, release_4.0.1, ticket-1009, ticket-1094-headless, ticket-1242-2d-resolution, ticket-1243, ticket-1249, ticket885, unittest-saveload

Children:

75df58b

Parents:

943cacb

Message:

added rectangular function for poly-dispersion

File:

• sansmodels/src/sans/models/c_models/parameters.cpp (modified) (2 diffs)

sansmodels/src/sans/models/c_models/parameters.cpp

@@ -98 +98 @@
         double vary, expo_value;
     vary = x-mean;
-    expo_value = -vary*vary/(2*sigma*sigma);
+    expo_value = -vary*vary/(2.0*sigma*sigma);
     //return 1.0;
     return exp(expo_value);
@@ -130 +130 @@
                           && ((*par).has_max==false || val<(*par).max)  ) {
                                 double _w = gaussian_weight(value, width, val);
+                                weights.insert(weights.end(), WeightPoint(val, _w));
+                        }
+                }
+        }
+}
+
+
+/**
+ * Flat dispersion
+ */
+
+RectangleDispersion :: RectangleDispersion() {
+        npts  = 21;
+        width = 0.0;
+        nsigmas = 1.0;
+};
+
+void RectangleDispersion :: accept_as_source(DispersionVisitor* visitor, void* from, void* to) {
+        visitor->rectangle_to_dict(from, to);
+}
+void RectangleDispersion :: accept_as_destination(DispersionVisitor* visitor, void* from, void* to) {
+        visitor->rectangle_from_dict(from, to);
+}
+
+double rectangle_weight(double mean, double sigma, double x) {
+        double vary, expo_value;
+    double sig = fabs(sigma);
+    if (x>= (mean-sig) && x<(mean+sig)){
+        return 1.0;
+    }
+    else{
+        return 0.0;
+    }
+}
+
+/**
+ * Flat dispersion
+ * @param mean: mean value
+ * @param sigma: half width of top hat function
+ * @param x: value at which the Flat is evaluated
+ * @return: value of the Flat
+ */
+void RectangleDispersion :: operator() (void *param, vector<WeightPoint> &weights){
+        // Check against zero width
+        if (width<=0) {
+                width = 0.0;
+                npts  = 1;
+                nsigmas = 1.0;
+        }
+
+        Parameter* par = (Parameter*)param;
+        double value = (*par)();
+
+        if (npts<2) {
+                weights.insert(weights.end(), WeightPoint(value, 1.0));
+        } else {
+                for(int i=0; i<npts; i++) {
+                        // We cover n(nsigmas) times sigmas on each side of the mean
+                        double val = value + width * (2.0*nsigmas*double(i)/double(npts-1) - nsigmas);
+                        if ( ((*par).has_min==false || val>(*par).min)
+                          && ((*par).has_max==false || val<(*par).max)  ) {
+                                double _w = rectangle_weight(value, width, val);
                                 weights.insert(weights.end(), WeightPoint(val, _w));
                         }