Changeset 63d4dd1 in sasmodels for sasmodels/models/hollow_rectangular_prism_thin_walls.c

Timestamp:

Nov 9, 2018 3:25:10 PM (5 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:

7126c04

Parents:

599993b9 (diff), cf3d0ce (diff)
Note: this is a merge changeset, the changes displayed below correspond to the merge itself.
Use the (diff) links above to see all the changes relative to each parent.

Message:

Merge branch 'beta_approx' into ticket-1015-gpu-mem-error

File:

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

sasmodels/models/hollow_rectangular_prism_thin_walls.c

@@ +1 @@
+static double
+shell_volume(double length_a, double b2a_ratio, double c2a_ratio)
+{
+    const double length_b = length_a * b2a_ratio;
+    const double length_c = length_a * c2a_ratio;
+    const double shell_volume = 2.0 * (length_a*length_b + length_a*length_c + length_b*length_c);
+    return shell_volume;
+}
+
 static double
 form_volume(double length_a, double b2a_ratio, double c2a_ratio)
 {
-    double length_b = length_a * b2a_ratio;
-    double length_c = length_a * c2a_ratio;
-    double vol_shell = 2.0 * (length_a*length_b + length_a*length_c + length_b*length_c);
-    return vol_shell;
+    const double length_b = length_a * b2a_ratio;
+    const double length_c = length_a * c2a_ratio;
+    const double form_volume = length_a * length_b * length_c;
+    return form_volume;
 }
 
 static double
-Iq(double q,
+radius_from_excluded_volume(double length_a, double b2a_ratio, double c2a_ratio)
+{
+    const double r_equiv = sqrt(length_a*length_a*b2a_ratio/M_PI);
+    const double length_c = length_a*c2a_ratio;
+    return 0.5*cbrt(0.75*r_equiv*(2.0*r_equiv*length_c + (r_equiv + length_c)*(M_PI*r_equiv + length_c)));
+}
+
+static double
+effective_radius(int mode, double length_a, double b2a_ratio, double c2a_ratio)
+{
+    switch (mode) {
+    default:
+    case 1: // equivalent cylinder excluded volume
+        return radius_from_excluded_volume(length_a, b2a_ratio, c2a_ratio);
+    case 2: // equivalent outer volume sphere
+        return cbrt(cube(length_a)*b2a_ratio*c2a_ratio/M_4PI_3);
+    case 3: // half length_a
+        return 0.5 * length_a;
+    case 4: // half length_b
+        return 0.5 * length_a*b2a_ratio;
+    case 5: // half length_c
+        return 0.5 * length_a*c2a_ratio;
+    case 6: // equivalent outer circular cross-section
+        return length_a*sqrt(b2a_ratio/M_PI);
+    case 7: // half ab diagonal
+        return 0.5*sqrt(square(length_a) * (1.0 + square(b2a_ratio)));
+    case 8: // half diagonal
+        return 0.5*sqrt(square(length_a) * (1.0 + square(b2a_ratio) + square(c2a_ratio)));
+    }
+}
+
+static void
+Fq(double q,
+    double *F1,
+    double *F2,
     double sld,
     double solvent_sld,
@@ -28 +71 @@
     const double v2b = M_PI_2;  //phi integration limits
 
-    double outer_sum = 0.0;
+    double outer_sum_F1 = 0.0;
+    double outer_sum_F2 = 0.0;
     for(int i=0; i<GAUSS_N; i++) {
         const double theta = 0.5 * ( GAUSS_Z[i]*(v1b-v1a) + v1a + v1b );
@@ -41 +85 @@
         const double termAT_theta = 8.0 * sin_c / (q*q*sin_theta*cos_theta);
 
-        double inner_sum = 0.0;
+        double inner_sum_F1 = 0.0;
+        double inner_sum_F2 = 0.0;
         for(int j=0; j<GAUSS_N; j++) {
             const double phi = 0.5 * ( GAUSS_Z[j]*(v2b-v2a) + v2a + v2b );
@@ -60 +105 @@
                 * ( cos_a*sin_b/cos_phi + cos_b*sin_a/sin_phi );
 
-            inner_sum += GAUSS_W[j] * square(AL+AT);
+            inner_sum_F1 += GAUSS_W[j] * (AL+AT);
+            inner_sum_F2 += GAUSS_W[j] * square(AL+AT);
         }
 
-        inner_sum *= 0.5 * (v2b-v2a);
-        outer_sum += GAUSS_W[i] * inner_sum * sin_theta;
+        inner_sum_F1 *= 0.5 * (v2b-v2a);
+        inner_sum_F2 *= 0.5 * (v2b-v2a);
+        outer_sum_F1 += GAUSS_W[i] * inner_sum_F1 * sin_theta;
+        outer_sum_F2 += GAUSS_W[i] * inner_sum_F2 * sin_theta;
     }
 
-    outer_sum *= 0.5*(v1b-v1a);
+    outer_sum_F1 *= 0.5*(v1b-v1a);
+    outer_sum_F2 *= 0.5*(v1b-v1a);
 
     // Normalize as in Eqn. (15) without the volume factor (as cancels with (V*DelRho)^2 normalization)
     // The factor 2 is due to the different theta integration limit (pi/2 instead of pi)
-    double answer = outer_sum/M_PI_2;
+    const double form_avg = outer_sum_F1/M_PI_2;
+    const double form_squared_avg = outer_sum_F2/M_PI_2;
 
     // Multiply by contrast^2. Factor corresponding to volume^2 cancels with previous normalization.
-    answer *= square(sld-solvent_sld);
+    const double contrast = sld - solvent_sld;
 
     // Convert from [1e-12 A-1] to [cm-1]
-    answer *= 1.0e-4;
-
-    return answer;
+    *F1 = 1e-2 * contrast * form_avg;
+    *F2 = 1e-4 * contrast * contrast * form_squared_avg;
 }