[GRASS-SVN] r65496 - grass-addons/grass7/vector/v.concave.hull

[svn_grass at osgeo.org]

Author: mlennert
Date: 2015-06-17 06:53:52 -0700 (Wed, 17 Jun 2015)
New Revision: 65496

Modified:
   grass-addons/grass7/vector/v.concave.hull/v.concave.hull.py
Log:
automatically reduce threshold if too high


Modified: grass-addons/grass7/vector/v.concave.hull/v.concave.hull.py
===================================================================
--- grass-addons/grass7/vector/v.concave.hull/v.concave.hull.py	2015-06-17 11:01:05 UTC (rev 65495)
+++ grass-addons/grass7/vector/v.concave.hull/v.concave.hull.py	2015-06-17 13:53:52 UTC (rev 65496)
@@ -128,6 +128,19 @@
     max_length = 0.0
     sortfile(tmp, tmp + ".sort")
     ppos = round(N * perc / 100)
+
+    perc_orig = perc
+    while ppos >= N and perc >= 90:
+        perc -= 1
+        ppos = round(N * perc / 100)
+
+    if perc == 89:
+        grass.fatal(_("Cannot calculate hull. Too few points."))
+
+    if perc_orig > perc:
+        thresh = int(perc) - 90
+        grass.warning(_('Threshold reduced to %d to calculate hull' % thresh ))
+
     inf = file(tmp + ".sort")
     l = 0
     for line in inf:
@@ -137,9 +150,6 @@
 	l += 1
     inf.close()
 
-    if max_length == 0.0:
-        grass.fatal(_("Cannot calculate hull. Try lowering the threshold."))
-
     grass.message(_("Feature selection..."))
     lines_concave = prefix + '_delaunay_lines_select'
     lines_concave_nocat = prefix + '_delaunay_lines_select_nocat'