Replace old raise form

scikits/image/color/colorconv.py

@@ -95,9 +95,9 @@ def convert_colorspace(arr, fromspace, tospace):
     fromspace = fromspace.upper()
     tospace = tospace.upper()
     if not fromspace in fromdict.keys():
-        raise ValueError, 'fromspace needs to be one of %s'%fromdict.keys()
+        raise ValueError('fromspace needs to be one of %s'%fromdict.keys())
     if not tospace in todict.keys():
-        raise ValueError, 'tospace needs to be one of %s'%todict.keys()
+        raise ValueError('tospace needs to be one of %s'%todict.keys())
 
     return todict[tospace](fromdict[fromspace](arr))
 
@@ -108,7 +108,7 @@ def _prepare_colorarray(arr, dtype=np.float32):
 
     if arr.ndim != 3 or arr.shape[2] != 3:
         msg = "the input array must be have a shape == (.,.,3))"
-        raise ValueError, msg
+        raise ValueError(msg)
 
     return arr.astype(dtype)
 

scikits/image/io/collection.py

@@ -128,7 +128,7 @@ class MultiImage(object):
         if -numframes <= n < numframes:
             n = n % numframes
         else:
-            raise IndexError, "There are only %s frames in the image"%numframes
+            raise IndexError("There are only %s frames in the image"%numframes)
 
         if self.conserve_memory:
             if not self._cached == n:
@@ -289,7 +289,7 @@ class ImageCollection(object):
         if -num <= n < num:
             n = n % num
         else:
-            raise IndexError, "There are only %s images in the collection"%num
+            raise IndexError("There are only %s images in the collection"%num)
         return n
 
     def __iter__(self):