BF: AttributeMap -- consider only int (+unsigned) and float to be num…

…eric labels

This generalizes the logic and thus unicode labels would also be mapped,
as well as any other odd type.  Use unicode labels for normal_feature_dataset

mvpa2/misc/attrmap.py

@@ -150,7 +150,7 @@ def to_numeric(self, attr):
         attr = np.asanyarray(attr)
 
         # no mapping if already numeric
-        if not np.issubdtype(attr.dtype, str) and not self.mapnumeric:
+        if attr.dtype.kind in 'iuf' and not self.mapnumeric:
             return attr
 
         if self._nmap is None:

mvpa2/misc/data_generators.py

@@ -124,7 +124,7 @@ def normal_feature_dataset(perlabel=50, nlabels=2, nfeatures=4, nchunks=5,
         # bring it 'under 1', since otherwise some classifiers have difficulties
         # during optimization
         data = 1.0 / (np.max(np.abs(data))) * data
-    labels = np.concatenate([np.repeat('L%d' % i, perlabel)
+    labels = np.concatenate([np.repeat(u'L%d' % i, perlabel)
                              for i in range(nlabels)])
     chunks = np.concatenate([np.repeat(range(nchunks),
                                        perlabel // nchunks)