Changeset 2bb0b26 in sasview for realSpaceModeling/pointsmodelpy/libpointsmodelpy/points_model.cc

Timestamp:

Sep 27, 2007 11:16:55 AM (17 years ago)

Author:

Mathieu Doucet <doucetm@…>

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:

02cb31a

Parents:

d1101bb

Message:

Added underlying 2D real-space simulation

File:

• realSpaceModeling/pointsmodelpy/libpointsmodelpy/points_model.cc (modified) (1 diff)

realSpaceModeling/pointsmodelpy/libpointsmodelpy/points_model.cc

@@ -375 +375 @@
   return I;
 }
+
+/*
+ * 2D simulation for oriented systems
+ * The beam direction is assumed to be in the z direction.
+ * 
+ * @param points: vector of space points
+ * @param qx: qx [A-1]
+ * @param qy: qy [A-1]
+ * @return: I(qx, qy) for the system described by the space points [cm-1]
+ * 
+ */
+double PointsModel::CalculateIQ_2D(const vector<Point3D>&points, double qx, double qy){
+        /*
+         * TODO: the vector of points should really be part of the class
+         *           This is a design flaw inherited from the original programmer.
+         */
+        
+        int size = points.size();
+
+        double cos_term = 0;
+        double sin_term = 0;
+        for (int i = 0; i < size; i++) {
+                //the sld for the pair of points
+        
+                double phase = qx*points[i].getX() + qy*points[i].getY();
+                                
+                cos_term += cos(phase) * points[i].getSLD();
+                sin_term += sin(phase) * points[i].getSLD();
+        
+        }                       
+
+        // P(q) = 1/V I(q) = (V/N)^2 (1/V) (cos_term^2 + sin_term^2) 
+        // We divide by N here and we will multiply by the density later.
+
+        return (cos_term*cos_term + sin_term*sin_term)/size;    
+}
+