Changeset 2a0b2b1 in sasmodels for sasmodels/models/hollow_cylinder.c

Timestamp:

Apr 14, 2017 8:30:29 AM (7 years ago)

Author:

Paul Kienzle <pkienzle@…>

Branches:

master, core_shell_microgels, magnetic_model, ticket-1257-vesicle-product, ticket_1156, ticket_1265_superball, ticket_822_more_unit_tests

Children:

fdd56a1

Parents:

9901384

Message:

restructure all 2D models to work with (qa,qb,qc) = rotate(qx,qy) rather than working with angles directly in preparation for revised jitter algorithm

File:

• sasmodels/models/hollow_cylinder.c (modified) (4 diffs)

sasmodels/models/hollow_cylinder.c

@@ -1 +1 @@
 double form_volume(double radius, double thickness, double length);
 double Iq(double q, double radius, double thickness, double length, double sld,
-        double solvent_sld);
+    double solvent_sld);
 double Iqxy(double qx, double qy, double radius, double thickness, double length, double sld,
-        double solvent_sld, double theta, double phi);
+    double solvent_sld, double theta, double phi);
 
 //#define INVALID(v) (v.radius_core >= v.radius)
@@ -14 +14 @@
 }
 
-
 static double
-_hollow_cylinder_kernel(double q,
-    double radius, double thickness, double length, double sin_val, double cos_val)
+_fq(double qab, double qc,
+    double radius, double thickness, double length)
 {
-    const double qs = q*sin_val;
-    const double lam1 = sas_2J1x_x((radius+thickness)*qs);
-    const double lam2 = sas_2J1x_x(radius*qs);
+    const double lam1 = sas_2J1x_x((radius+thickness)*qab);
+    const double lam2 = sas_2J1x_x(radius*qab);
     const double gamma_sq = square(radius/(radius+thickness));
-    //Note: lim_{thickness -> 0} psi = sas_J0(radius*qs)
-    //Note: lim_{radius -> 0} psi = sas_2J1x_x(thickness*qs)
-    const double psi = (lam1 - gamma_sq*lam2)/(1.0 - gamma_sq); //SRK 10/19/00
-    const double t2 = sas_sinx_x(0.5*q*length*cos_val);
+    //Note: lim_{thickness -> 0} psi = sas_J0(radius*qab)
+    //Note: lim_{radius -> 0} psi = sas_2J1x_x(thickness*qab)
+    const double psi = (lam1 - gamma_sq*lam2)/(1.0 - gamma_sq);    //SRK 10/19/00
+    const double t2 = sas_sinx_x(0.5*length*qc);
     return psi*t2;
 }
@@ -43 +41 @@
 {
     const double lower = 0.0;
-    const double upper = 1.0;           //limits of numerical integral
+    const double upper = 1.0;        //limits of numerical integral
 
-    double summ = 0.0;                  //initialize intergral
+    double summ = 0.0;            //initialize intergral
     for (int i=0;i<76;i++) {
-        const double cos_val = 0.5*( Gauss76Z[i] * (upper-lower) + lower + upper );
-        const double sin_val = sqrt(1.0 - cos_val*cos_val);
-        const double inter = _hollow_cylinder_kernel(q, radius, thickness, length,
-                                                     sin_val, cos_val);
-        summ += Gauss76Wt[i] * inter * inter;
+        const double cos_theta = 0.5*( Gauss76Z[i] * (upper-lower) + lower + upper );
+        const double sin_theta = sqrt(1.0 - cos_theta*cos_theta);
+        const double form = _fq(q*sin_theta, q*cos_theta,
+                                radius, thickness, length);
+        summ += Gauss76Wt[i] * form * form;
     }
 
@@ -66 +64 @@
     double q, sin_alpha, cos_alpha;
     ORIENT_SYMMETRIC(qx, qy, theta, phi, q, sin_alpha, cos_alpha);
-    const double Aq = _hollow_cylinder_kernel(q, radius, thickness, length,
-        sin_alpha, cos_alpha);
+    const double qab = q*sin_alpha;
+    const double qc = q*cos_alpha;
+
+    const double form = _fq(qab, qc, radius, thickness, length);
 
     const double vol = form_volume(radius, thickness, length);
-    return _hollow_cylinder_scaling(Aq*Aq, solvent_sld-sld, vol);
+    return _hollow_cylinder_scaling(form*form, solvent_sld-sld, vol);
 }
-