Index: wflow-py/wflow/pcrut.py
===================================================================
diff -u -rc7476868c506252d099ab57c9909e317b43aeeee -r48dc525cc2925dade77d288a9ecf774179acd687
--- wflow-py/wflow/pcrut.py	(.../pcrut.py)	(revision c7476868c506252d099ab57c9909e317b43aeeee)
+++ wflow-py/wflow/pcrut.py	(.../pcrut.py)	(revision 48dc525cc2925dade77d288a9ecf774179acd687)
@@ -184,15 +184,14 @@
         result = spreadzone(ordinal(cover(Unq,0)),0,1)
         result = areaaverage(inputmap,result);
     
-    return result 
+    return result
 
 
 
 
-_tableToMap_LastTbl = {}
-_tableToMap_LastMap = {}
 
 
+
 def tableToMapSparse (step, table, map):
     """Reads a pcraster.tbl file for step and assigns using the map in map.
     The behaviour of is a bit similar to the timeinputSparse
@@ -221,34 +220,36 @@
     
     
     """
-    global _tableToMap_LastTbl
-    global _tableToMap_LastMap
     global debug
-    
+
+    if not hasattr(tableToMapSparse,"_tableToMap_LastTbl"):
+        _tableToMap_LastTbl = {}
+        _tableToMap_LastMap = {}
+
     # construct filenames
     fname_map = map + str(step) + ".map"
     fname_tbl = table + str(step) + ".tbl"
 
-    
+
     if os.path.exists(fname_map):
-	    print "found: " + fname_map
-	    _tableToMap_LastMap[map] = step
-  	    
+        print "found: " + fname_map
+        tableToMapSparse._tableToMap_LastMap[map] = step
+
     if os.path.exists(fname_tbl):
-	    print "found: " + fname_tbl
-	    _tableToMap_LastTbl[table] = step
+        print "found: " + fname_tbl
+        tableToMapSparse._tableToMap_LastTbl[table] = step
 
-    if _tableToMap_LastTbl.has_key(table) == False:
-	    fname_tbl = table + ".tbl"
+    if tableToMapSparse._tableToMap_LastTbl.has_key(table) == False:
+        fname_tbl = table + ".tbl"
     else:
-	    fname_tbl = table + str(_tableToMap_LastTbl[table]) + ".tbl"
+        fname_tbl = table + str(tableToMapSparse._tableToMap_LastTbl[table]) + ".tbl"
 
-    if _tableToMap_LastMap.has_key(map) == False:
-	    fname_map = map + ".map"
+    if tableToMapSparse._tableToMap_LastMap.has_key(map) == False:
+        fname_map = map + ".map"
     else:
-	    fname_map = map + str(_tableToMap_LastMap[map]) + ".map"
-        
-    
+        fname_map = map + str(tableToMapSparse._tableToMap_LastMap[map]) + ".map"
+
+
     rmat = lookupscalar(str(fname_tbl),str(fname_map))
 
     return rmat