Changeset f629e346 in sasview for sansmodels/src/sans/models/FractalModel.py

Timestamp:

Mar 25, 2008 4:19:00 PM (16 years ago)

Author:

Mathieu Doucet <doucetm@…>

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:

6b8399b

Parents:

3db3895

Message:

Updated tests to reflect proper math (took test funcs from Igor). Still need to look into incoherence btw Igor docs and Igor code!

File:

• sansmodels/src/sans/models/FractalModel.py (modified) (2 diffs)

sansmodels/src/sans/models/FractalModel.py

@@ -67 +67 @@
     def _Block(self,x):
         
+        
+        
         return 1.0 + (math.sin((self.params['fractal_dim']-1.0) * math.atan(x * self.params['corr_length']))\
              * self.params['fractal_dim'] * gamma(self.params['fractal_dim']-1.0))\
-           /( math.pow( (x*self.params['radius']),self.params['fractal_dim'])*\
-           ( 1.0 + 1.0/((x**2)*(self.params['corr_length']**2)),(self.params['fractal_dim']-1.0)/2.0))      
+           /( math.pow( (x*self.params['radius']), self.params['fractal_dim'])*\
+           math.pow( 1.0 + 1.0/((x**2)*(self.params['corr_length']**2)),(self.params['fractal_dim']-1.0)/2.0))   
            
     def _Spherical(self,x):
         """
-            F(x) = [sin(x)-xcos(x)]/3*(x**3)
+            F(x) = 3*[sin(x)-xcos(x)]/x**3
         """
-        return (math.sin(x)-x*math.cos(x))/(3.0*math.pow(x,3.0))
+        return 3.0*(math.sin(x)-x*math.cos(x))/(math.pow(x,3.0))
         
     def _scatterRanDom(self,x):
@@ -85 +87 @@
         delta = self.params['block_sld']-self.params['solvent_sld']
         
-        return self.params['scale']* V *(delta**2)*\
+        return 1.0e8*self.params['scale']* V *(delta**2)*\
                 (self._Spherical(x*self.params['radius'])**2)