Changeset c1c29b6 in sasview for sansmodels/src/sans/models/c_extensions/lamellarPS.c

Timestamp:

Aug 21, 2009 12:34:33 PM (15 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:

14c3887

Parents:

bda194e3

Message:

some corrections and removed polydispersity from inside of function and set dQ =0

File:

• sansmodels/src/sans/models/c_extensions/lamellarPS.c (modified) (3 diffs)

sansmodels/src/sans/models/c_extensions/lamellarPS.c

@@ -10 +10 @@
 #include <stdlib.h>
 
+/*LamellarPS_kernel() was moved from libigor to get rid of polydipersity in del(thickness) that we provide from control panel.
+/*      LamellarPSX  :  calculates the form factor of a lamellar structure - with S(q) effects included
+-------
+------- resolution effects ARE NOT included, but only a CONSTANT default value, not the real q-dependent resolution!!
+
+        */
+double
+LamellarPS_kernel(double dp[], double q)
+{
+        double scale,dd,del,contr,NN,Cp,bkg;            //local variables of coefficient wave
+        double inten, qval,Pq,Sq,alpha,temp,t1,t2,t3,dQ;
+        double Pi,Euler,dQDefault,fii;
+        int ii,NNint;
+        Euler = 0.5772156649;           // Euler's constant
+        dQDefault = 0.0;//0.0025;               //[=] 1/A, q-resolution, default value
+        dQ = dQDefault;
+
+        Pi = 4.0*atan(1.0);
+        qval = q;
+
+        scale = dp[0];
+        dd = dp[1];
+        del = dp[2];
+        contr = dp[3];
+        NN = trunc(dp[4]);              //be sure that NN is an integer
+        Cp = dp[5];
+        bkg = dp[6];
+
+        Pq = 2.0*contr*contr/qval/qval*(1.0-cos(qval*del));
+
+        NNint = (int)NN;                //cast to an integer for the loop
+        ii=0;
+        Sq = 0.0;
+        for(ii=1;ii<(NNint-1);ii+=1) {
+
+                fii = (double)ii;               //do I really need to do this?
+
+                temp = 0.0;
+                alpha = Cp/4.0/Pi/Pi*(log(Pi*ii) + Euler);
+                t1 = 2.0*dQ*dQ*dd*dd*alpha;
+                t2 = 2.0*qval*qval*dd*dd*alpha;
+                t3 = dQ*dQ*dd*dd*ii*ii;
+
+                temp = 1.0-ii/NN;
+                temp *= cos(dd*qval*ii/(1.0+t1));
+                temp *= exp(-1.0*(t2 + t3)/(2.0*(1.0+t1)) );
+                temp /= sqrt(1.0+t1);
+
+                Sq += temp;
+        }
+
+        Sq *= 2.0;
+        Sq += 1.0;
+
+        inten = 2.0*Pi*scale*Pq*Sq/(dd*qval*qval);
+
+        inten *= 1.0e8;         // 1/A to 1/cm
+
+    return(inten+bkg);
+}
 
 /**
@@ -18 +78 @@
  */
 double lamellarPS_analytical_1D(LamellarPSParameters *pars, double q) {
-        double dp[8];
+        double dp[7];
 
         // Fill paramater array
@@ -24 +84 @@
         dp[1] = pars->spacing;
         dp[2] = pars->delta;
-        dp[3] = pars->sigma;
-        dp[4] = pars->contrast;
-        dp[5] = pars->n_plates;
-        dp[6] = pars->caille;
-        dp[7] = pars->background;
+        dp[3] = pars->contrast;
+        dp[4] = pars->n_plates;
+        dp[5] = pars->caille;
+        dp[6] = pars->background;
 
         // Call library function to evaluate model
-        return LamellarPS(dp, q);
+        return LamellarPS_kernel(dp, q);
 }
 /**