Changeset 593 for sans/XOP_Dev/SANSAnalysis

Timestamp:

Nov 4, 2009 1:28:03 PM (13 years ago)

Author:

srkline

Message:

Added new model functions (see ticket #239) to the XOP, also added to the library.

Location:

sans/XOP_Dev/SANSAnalysis/lib

Files:

• libSphere.c (modified) (1 diff)
• libSphere.h (modified) (1 diff)

sans/XOP_Dev/SANSAnalysis/lib/libSphere.c

@@ -2124 +2124 @@
 }
 
+// scattering from a uniform sphere with a Gaussian size distribution
+//
+double
+FuzzySpheres(double dp[], double q)
+{
+        double pi,x;
+        double scale,rad,pd,sig,rho,rhos,bkg,delrho,sig_surf,f2,bes,vol,f;              //my local names
+        double va,vb,zi,yy,summ,inten;
+        int nord=20,ii;
+        
+        pi = 4.0*atan(1.0);
+        x= q;
+        
+        scale=dp[0];
+        rad=dp[1];
+        pd=dp[2];
+        sig=pd*rad;
+        sig_surf = dp[3];
+        rho=dp[4];
+        rhos=dp[5];
+        delrho=rho-rhos;
+        bkg=dp[6];
+        
+                        
+        va = -4.0*sig + rad;
+        if (va<0) {
+                va=0;           //to avoid numerical error when  va<0 (-ve q-value)
+        }
+        vb = 4.0*sig +rad;
+        
+        summ = 0.0;             // initialize integral
+        for(ii=0;ii<nord;ii+=1) {
+                // calculate Gauss points on integration interval (r-value for evaluation)
+                zi = ( Gauss20Z[ii]*(vb-va) + vb + va )/2.0;
+                // calculate sphere scattering
+                //
+                //handle q==0 separately
+                if (x==0.0) {
+                        f2 = 4.0/3.0*pi*zi*zi*zi*delrho*delrho*1.0e8;
+                        f2 *= exp(-0.5*sig_surf*sig_surf*x*x);
+                        f2 *= exp(-0.5*sig_surf*sig_surf*x*x);
+                } else {
+                        bes = 3.0*(sin(x*zi)-x*zi*cos(x*zi))/(x*x*x)/(zi*zi*zi);
+                        vol = 4.0*pi/3.0*zi*zi*zi;
+                        f = vol*bes*delrho;             // [=] A
+                        f *= exp(-0.5*sig_surf*sig_surf*x*x);
+                        // normalize to single particle volume, convert to 1/cm
+                        f2 = f * f / vol * 1.0e8;               // [=] 1/cm
+                }
+        
+                yy = Gauss20Wt[ii] *  Gauss_distr(sig,rad,zi) * f2;
+                yy *= 4.0*pi/3.0*zi*zi*zi;              //un-normalize by current sphere volume
+                
+                summ += yy;             //add to the running total of the quadrature
+                
+                
+        }
+        // calculate value of integral to return
+        inten = (vb-va)/2.0*summ;
+        
+        //re-normalize by polydisperse sphere volume
+        inten /= (4.0*pi/3.0*rad*rad*rad)*(1.0+3.0*pd*pd);
+        
+        inten *= scale;
+        inten += bkg;
+        
+    return(inten);      //scale, and add in the background
+}
+
+

sans/XOP_Dev/SANSAnalysis/lib/libSphere.h

@@ -30 +30 @@
 double FCC_ParaCrystal(double dp[], double q);
 double SC_ParaCrystal(double dp[], double q);
+double FuzzySpheres(double dp[], double q);
 
 //function prototypes