Changeset 7105 for anuga_core/source/anuga

Timestamp:

May 27, 2009, 4:25:47 PM (16 years ago)

Author:

ole

Message:

Optimised compute_fluxes by disabling limitation of momentum perpendicular to the x-axis. Speeds calculated from the x-momentum are still being limited according to the _compute_speeds. All tests pass and the overall improvement is as follows:
For the simple profile compute_fluxes improved from 4.284s to 3.372s and the overall runtime of evolve from 10.909s to 9.941s. This is an overall speedup of more than 8%.

For the okushiri profile example the improvement of compute_fluxes is from 129.432s to 111.703s and the overall runtime was reduced from 312.336s to 293.286s or about 6% improvement. This is probably the more realistic profile.

Location:

anuga_core/source/anuga/shallow_water

Files:

• shallow_water_ext.c (modified) (3 diffs)
• test_data_manager.py (modified) (6 diffs)
• test_shallow_water_domain.py (modified) (2 diffs)

anuga_core/source/anuga/shallow_water/shallow_water_ext.c

@@ -180 +180 @@
   
   if (*h < epsilon) {
-    *h = 0.0;  //Could have been negative
+    *h = 0.0;  // Could have been negative
     u = 0.0;
   } else {
@@ -272 +272 @@
   double w_left, h_left, uh_left, vh_left, u_left;
   double w_right, h_right, uh_right, vh_right, u_right;
-  double v_left, v_right;  
+  //double v_left, v_right;  
   double s_min, s_max, soundspeed_left, soundspeed_right;
   double denom, inverse_denominator, z;
@@ -317 +317 @@
   vh_right = q_right_rotated[2];
 
-  // Limit y-momentum if necessary  
-  v_left = _compute_speed(&vh_left, &h_left, epsilon, h0);
-  v_right = _compute_speed(&vh_right, &h_right, epsilon, h0);
+  // Limit y-momentum if necessary 
+  // Leaving this out, improves speed significantly (Ole 27/5/2009)
+  // All validation tests pass, so do we really need it anymore? 
+  //v_left = _compute_speed(&vh_left, &h_left, epsilon, h0);
+  //v_right = _compute_speed(&vh_right, &h_right, epsilon, h0);
 
   // Maximal and minimal wave speeds

anuga_core/source/anuga/shallow_water/test_data_manager.py

@@ -258 +258 @@
         
         range = fid.variables['xmomentum_range'][:]
-        ##print range
+        #print range
         assert num.allclose(range,[0,0.4695096]) or \
                num.allclose(range,[0,0.47790655]) or\
                num.allclose(range,[0,0.46941957]) or\
-               num.allclose(range,[0,0.47769409])
+               num.allclose(range,[0,0.47769409]) or\
+               num.allclose(range,[0,0.47738948])
 
         
         range = fid.variables['ymomentum_range'][:]
-        ##print range
+        #print range
         assert num.allclose(range,[0,0.02174380]) or\
                num.allclose(range,[0,0.02174439]) or\
                num.allclose(range,[0,0.02283983]) or\
                num.allclose(range,[0,0.0217342]) or\
-               num.allclose(range,[0,0.0227564]) # Old slope limiters 
+               num.allclose(range,[0,0.02258024]) or\
+               num.allclose(range,[0,0.0227564]) # Old slope limiters
+
         
         fid.close()
@@ -343 +346 @@
 
         extrema = fid.variables['xmomentum.extrema'][:]
-        assert num.allclose(extrema,[-0.06062178, 0.47873023]) or num.allclose(extrema, [-0.06062178, 0.47847986])
+        assert num.allclose(extrema,[-0.06062178, 0.47873023]) or\
+            num.allclose(extrema, [-0.06062178, 0.47847986]) or\
+            num.allclose(extrema, [-0.06062178, 0.47848481]) # 27/5/9            
         
         extrema = fid.variables['ymomentum.extrema'][:]
@@ -11088 +11093 @@
         for t in range(t_end+1):
             for i in range(3):
-                assert num.allclose(f(t, i), [1, 2, 0])
+                assert num.allclose(f(t, i), [1, 2, 0], atol=1.0e-6)
             
 
@@ -11125 +11130 @@
 
         #print i, Q
-        assert num.allclose(Q, 0)        
+        assert num.allclose(Q, 0, atol=1.0e-5)        
 
 
@@ -11222 +11227 @@
             for i in range(3):
                 #print i, t, f(t, i)            
-                assert num.allclose(f(t, i), [w, uh, 0])
+                assert num.allclose(f(t, i), [w, uh, 0], atol=1.0e-6)
             
 
@@ -11322 +11327 @@
             for i in range(3):
                 #print i, t, f(t, i)
-                assert num.allclose(f(t, i), [w, uh, 0])
+                assert num.allclose(f(t, i), [w, uh, 0], atol=1.0e-6)
             
 

anuga_core/source/anuga/shallow_water/test_shallow_water_domain.py

@@ -1616 +1616 @@
             assert num.allclose(w_t, w)
             assert num.allclose(uh_t, uh)            
-            assert num.allclose(vh_t, 0.0)                        
+            assert num.allclose(vh_t, 0.0, atol=1.0e-6)                        
             
             
@@ -1712 +1712 @@
             assert num.allclose(w_t, w)
             assert num.allclose(uh_t, uh)            
-            assert num.allclose(vh_t, 0.0)                        
+            assert num.allclose(vh_t, 0.0, atol=1.0e-6)