Changeset a5e14410 in sasview for sansmodels/src/sans

Timestamp:

Sep 16, 2011 4:48:48 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:

b9958b3

Parents:

fafdfd3

Message:

safer default values for polydispersion and lognormal fix

File:

• sansmodels/src/sans/models/c_models/parameters.cpp (modified) (10 diffs)

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

@@ -91 +91 @@
 
 GaussianDispersion :: GaussianDispersion() {
-        npts  = 11;
+        npts  = 100;
         width = 0.0;
-        nsigmas = 2.5;
+        nsigmas = 10;
 };
 
@@ -123 +123 @@
                 width = 0.0;
                 npts  = 1;
-                nsigmas = 2.5;
+                nsigmas = 10;
         }
 
@@ -158 +158 @@
 
 RectangleDispersion :: RectangleDispersion() {
-        npts  = 11;
+        npts  = 100;
         width = 0.0;
         nsigmas = 1.73205;
@@ -228 +228 @@
 
 LogNormalDispersion :: LogNormalDispersion() {
-        npts  = 15;
+        npts  = 100;
         width = 0.0;
-        nsigmas = 4.0;
+        nsigmas = 10.0;
 };
 
@@ -243 +243 @@
 
         double sigma2 = pow(sigma, 2.0);
-        return 1.0/(x*sigma) * exp( -pow((log(x) -log(mean)), 2.0) / (2.0*sigma2));
+        return 1.0/(x*sigma) * exp( -pow((log(x) - mean), 2.0) / (2.0*sigma2));
 
 }
@@ -259 +259 @@
                 width = 0.0;
                 npts  = 1;
-                nsigmas = 4.0;
+                nsigmas = 10.0;
         }
 
@@ -265 +265 @@
         double value = (*par)();
         double sig;
+        double log_value;
         if (npts<2) {
                 weights.insert(weights.end(), WeightPoint(value, 1.0));
@@ -272 +273 @@
                         if ((*par).has_min==false){
                                 // sig  for angles
-                                sig = width / value;
+                                sig = width;
                         }
                         else{
                                 // by lognormal definition, PD is same as sigma
-                                sig = width;
-                        }
-
+                                sig = width * value;
+                        }
+                        
                         // We cover n(nsigmas) times sigmas on each side of the mean
+                        //constant bin in real space
                         double val = value + sig * (2.0*nsigmas*double(i)/double(npts-1) - nsigmas);
-
+                        // sigma in the lognormal function is in ln(R) space, thus needs converting
+                        sig = fabs(sig/value); 
                         if ( ((*par).has_min==false || val>(*par).min)
                           && ((*par).has_max==false || val<(*par).max)  ) {
-                                double _w = lognormal_weight(value, sig, val);
+                                double _w = lognormal_weight(log(value), sig, val);
                                 weights.insert(weights.end(), WeightPoint(val, _w));
+                                //printf("%g \t %g\n",val,_w);
+
                         }
                 }
@@ -298 +303 @@
 
 SchulzDispersion :: SchulzDispersion() {
-        npts  = 11;
+        npts  = 100;
         width = 0.0;
-        nsigmas = 3.0;
+        nsigmas = 10.0;
 };
 
@@ -332 +337 @@
                 width = 0.0;
                 npts  = 1;
-                nsigmas = 3.0;
+                nsigmas = 10.0;
         }