ENH: Add SpatialImage._spatial_dims slicer

Author: effigies

nibabel/minc1.py

@@ -319,6 +319,12 @@ def from_file_map(klass, file_map):
             data = klass.ImageArrayProxy(minc_file)
         return klass(data, affine, header, extra=None, file_map=file_map)
 
+    @property
+    def _spatial_dims(self):
+        if len(self.shape) > 3:
+            return slice(1, 4)
+        return slice(0, 3)
+
 
 load = Minc1Image.load
 

nibabel/spatialimages.py

@@ -325,6 +325,9 @@ class ImageDataError(Exception):
 class SpatialImage(DataobjImage):
     ''' Template class for volumetric (3D/4D) images '''
     header_class = SpatialHeader
+    # Make a strong assumption that the first three dimensions are spatial
+    # Subclasses/images for which this is not true should change this attribute
+    _spatial_dims = slice(0, 3)
 
     class Slicer(object):
         def __init__(self, img):