Merge pull request #266 from hifabian/master

Scaling adjustments for windef and output notation

Author: alexlib

openpiv/test/test_tools.py

@@ -43,7 +43,7 @@ def test_display_vector_field(file_a=_file_a, file_b=_file_b, test_file=_test_fi
     display_vector_field('tmp.txt', on_img=True, image_name=file_a, ax=ax)
     decorators.remove_ticks_and_titles(fig)
     fig.savefig('./tmp.png')
-    res = compare.compare_images('./tmp.png', test_file, 0.001)
+    res = compare.compare_images('./tmp.png', test_file, 0.05)
     assert res is None
 
 def test_file_patterns():
@@ -62,4 +62,4 @@ def test_file_patterns():
         # settings.frame_pattern_b = '(1+2),(3+4)'
     """
 
-    
+    

openpiv/tools.py

@@ -329,7 +329,7 @@ def find_boundaries(threshold, list_img1, list_img2, filename, picname):
     return list_bound
 
 
-def save(x, y, u, v, mask, filename, fmt="%8.4f", delimiter="\t"):
+def save(x, y, u, v, mask, filename, fmt="%.4e", delimiter="\t"):
     """Save flow field to an ascii file.
 
     Parameters
@@ -652,4 +652,4 @@ def transform_coordinates(x, y, u, v):
     y = y[::-1, :]
     v *= -1
     return x, y, u, v
-        
+        

openpiv/windef.py

@@ -321,6 +321,9 @@ def func(args):
         u = u.filled(0.)
         v = v.filled(0.)
 
+        # pixel / frame -> pixel / second
+        u /= settings.dt 
+        v /= settings.dt
         # "scales the results pixel-> meter"
         x, y, u, v = scaling.uniform(x, y, u, v,
                                      scaling_factor=settings.scaling_factor)