follow up 4fb2898

Author: alexbruy

python/plugins/processing/core/parameters.py

@@ -367,8 +367,14 @@ def __init__(self, name='', description='', minValue=None, maxValue=None,
         except:
             self.default = float(default)
             self.isInteger = False
-        self.min = int(minValue) if self.isInteger else float(minValue)
-        self.max = int(maxValue) if self.isInteger else float(maxValue)
+        if minValue is not None:
+            self.min = int(minValue) if self.isInteger else float(minValue)
+        else:
+            self.min = None
+        if maxValue is not None:
+            self.max = int(maxValue) if self.isInteger else float(maxValue)
+        else:
+            self.max = None
         self.value = None
 
     def setValue(self, n):