make num_dim a read-only property

Author: Ben Cipollini

nibabel/gifti/gifti.py

@@ -233,7 +233,6 @@ class GiftiDataArray(xml.XmlSerializable):
     intent = int
     datatype = int
     ind_ord = int
-    num_dim = int
     dims = list
     encoding = int
     endian = int
@@ -266,6 +265,9 @@ def __init__(self, data=None,
         self.encoding = encoding
         self.endian = endian
 
+    @property
+    def num_dim(self):
+        return len(self.dims)
 
     @classmethod
     def from_array(klass,
@@ -309,7 +311,6 @@ def from_array(klass,
         if meta is None:
             meta = {}
         cda = klass(darray)
-        cda.num_dim = len(darray.shape)
         cda.dims = list(darray.shape)
         if datatype is None:
             cda.datatype = data_type_codes.code[darray.dtype]

nibabel/gifti/parse_gifti_fast.py

@@ -167,14 +167,14 @@ def StartElementHandler(self, name, attrs):
             if "ArrayIndexingOrder" in attrs:
                 self.da.ind_ord = array_index_order_codes.code[
                     attrs["ArrayIndexingOrder"]]
-            if "Dimensionality" in attrs:
-                self.da.num_dim = int(attrs["Dimensionality"])
-            for i in range(self.da.num_dim):
+            num_dim = int(attrs.get("Dimensionality", 0))
+            for i in range(num_dim):
                 di = "Dim%s" % str(i)
                 if di in attrs:
                     self.da.dims.append(int(attrs[di]))
             # dimensionality has to correspond to the number of DimX given
-            assert len(self.da.dims) == self.da.num_dim
+            # TODO (bcipolli): don't assert; raise parse warning, and recover.
+            assert len(self.da.dims) == num_dim
             if "Encoding" in attrs:
                 self.da.encoding = gifti_encoding_codes.code[attrs["Encoding"]]
             if "Endian" in attrs: