BF: generalize date grid formatters for Py3, uint

In Python 3, np.int64 no longer subclasses np.int, so the test for
integers was not working, when choosing formatters.  Unsigned ints
should also use the integer formatter.

datarray/print_grid.py

@@ -218,16 +218,21 @@ def format(self, value, width=None):
         result = '{0}{1}j'.format(real_part, imag_part)
         return '{0:<{width}}'.format(result, width=width)
 
+
+# Formatters for numpy dtype kinds
+_KIND2FORMAT = dict(b = BoolFormatter,
+                    u = IntFormatter,
+                    i = IntFormatter,
+                    f = FloatFormatter,
+                    c = ComplexFormatter)
+
+
 def get_formatter(arr):
     """
     Get a formatter for this array's data type, and prime it on this array.
     """
-    typeobj = arr.dtype.type
-    if issubclass(typeobj, np.bool): return BoolFormatter(arr)
-    elif issubclass(typeobj, np.int): return IntFormatter(arr)
-    elif issubclass(typeobj, np.floating): return FloatFormatter(arr)
-    elif issubclass(typeobj, np.complex): return ComplexFormatter(arr)
-    else: return StrFormatter(arr)
+    return _KIND2FORMAT.get(arr.dtype.kind, StrFormatter)(arr)
+
 
 def grid_layout(arr, width=75, height=10):
     """

datarray/tests/test_bugfixes.py

@@ -53,12 +53,17 @@ def test_bug34():
     from datarray.print_grid import datarray_to_string
     from datetime import date as D
     A = DataArray([[1,2],[3,4]], [('row', ('a', D(2010,1,1))),('col', 'cd')])
-    nt.assert_equal(datarray_to_string(A), """row       col                
+    exp_out = """row       col                
 --------- -------------------
           c         d        
 a                 1         2
-2010-01-0         3         4""")
-
+2010-01-0         3         4"""
+    nt.assert_equal(datarray_to_string(A), exp_out)
+    # Output for unsigned integers
+    B = A.astype(np.uint32)
+    nt.assert_equal(datarray_to_string(B), exp_out)
+
+
 def test_bug35():
     "Bug 35"
     txt_array = DataArray(['a','b'], axes=['dummy'])