Changeset 459 for sans/Dev/trunk/NCNR_User_Procedures/Reduction/SANS/MultScatter_MonteCarlo_2D.ipf

Timestamp:

Dec 3, 2008 12:49:15 PM (14 years ago)

Author:

srkline

Message:

Fixes from Lionel's bug in the calculation of Qx and Qy. Qx and Qy were not being properly calculated as components of Q and phi (azimuthal angle). Only an effect at the largest q-values (> 0.3) and even then, only in the 3rd decimal place.This incorrect calculation was only visible on the 2D data display, and in the QxQy? ASCII export. Not a terrible bug, not worth immediate release of a patch.

File:

• sans/Dev/trunk/NCNR_User_Procedures/Reduction/SANS/MultScatter_MonteCarlo_2D.ipf (modified) (1 diff)

sans/Dev/trunk/NCNR_User_Procedures/Reduction/SANS/MultScatter_MonteCarlo_2D.ipf

@@ -601 +601 @@
 End
 
-//phi is defined from +x axis, proceeding CCW around [0,2Pi]
-Threadsafe Function FindPhi(vx,vy)
-        variable vx,vy
-        
-        variable phi
-        
-        phi = atan(vy/vx)               //returns a value from -pi/2 to pi/2
-        
-        // special cases
-        if(vx==0 && vy > 0)
-                return(pi/2)
-        endif
-        if(vx==0 && vy < 0)
-                return(3*pi/2)
-        endif
-        if(vx >= 0 && vy == 0)
-                return(0)
-        endif
-        if(vx < 0 && vy == 0)
-                return(pi)
-        endif
-        
-        
-        
-        if(vx > 0 && vy > 0)
-                return(phi)
-        endif
-        if(vx < 0 && vy > 0)
-                return(abs(phi) + pi/2)
-        endif
-        if(vx < 0 && vy < 0)
-                return(phi + pi)
-        endif
-        if( vx > 0 && vy < 0)
-                return(abs(phi) + 3*pi/2)
-        endif
-        
-        return(phi)
-end