Changeset 974 for sans/XOP_Dev/MonteCarlo/MonteCarlo_Main.c

Timestamp:

Jan 19, 2016 11:48:55 AM (7 years ago)

Author:

srkline

Message:

adding the function for the basic metropolis algorithm.

File:

• sans/XOP_Dev/MonteCarlo/MonteCarlo_Main.c (modified) (4 diffs)

sans/XOP_Dev/MonteCarlo/MonteCarlo_Main.c

@@ -15 +15 @@
 #include "MonteCarlo.h"
 #include "DebyeSpheres.h"
+#include "Metropolis.h"
 
 
@@ -33 +34 @@
 
 
+// corrected Feb 2013 to return values in [0,127] rather than detector coordinates (which are passed in)
+// -- also corrected the pixel calculation
 int
 FindPixel(double testQ, double testPhi, double lam, double yg_d, double sdd,
                   double pixSize, double xCtr, double yCtr, long *xPixel, long *yPixel) {
         
-        double theta,dy,dx,qx,qy,pi;
-        pi = 4.0*atan(1.0);     
+//      double theta,dy,dx,qx,qy,pi;
+        double pi,two_theta,dist,dx,dy;
+        
+        pi = 4.0*atan(1.0);
+
+/* OLD way
         //decompose to qx,qy
         qx = testQ*cos(testPhi);
@@ -57 +64 @@
 //      *xPixel = lround(xCtr + dx/pixSize);
         *xPixel = MC_round(xCtr + dx/pixSize);
+
+*/
+        
+        // corrected way Feb 2013
+        two_theta = 2.0*asin(testQ*lam/4.0/pi);
+        dist = sdd*tan(two_theta);                      //hypot in det plane
+        
+        dx = dist*cos(testPhi);
+        dy = dist*sin(testPhi);
+        *xPixel = MC_round(dx/pixSize + xCtr);
+        *yPixel = MC_round(dy/pixSize + yCtr + yg_d/pixSize);           //shift down due to gravity
+        
+        // to array coordinates rather than detector coordinates
+        *xPixel -= 1;
+        *yPixel -= 1;
+        
         
         //if on detector, return xPix and yPix values, otherwise -1
@@ -387 +410 @@
                         return((long)binSLDDistanceX);
                         break;
+                case 9:                                         // 
+                        return((long)MetropolisX);
+                        break;
         }
         return(NIL);