Fix map write for custom axis name

gammapy/maps/geom.py

@@ -45,34 +45,40 @@ def make_axes_cols(axes, axis_names=None):
 
     Parameters
     ----------
-    axes : list of `~MapAxis`
-
-    axis_names : list of str
+    axes : list
+        Python list of `MapAxis` objects
 
+    Returns
+    -------
+    cols : list
+        Python list of `~astropy.io.fits.Column`
     """
-    colname = {
-        'energy': ['ENERGY', 'E_MIN', 'E_MAX'],
-        'time': ['TIME', 'T_MIN', 'T_MAX'],
-    }
+    size = np.prod([ax.nbin for ax in axes])
+    chan = np.arange(0, size)
+    cols = [fits.Column('CHANNEL', 'I', array=chan), ]
 
     if axis_names is None:
         axis_names = [ax.name for ax in axes]
+    axis_names = [_.upper() for _ in axis_names]
 
-    size = np.prod([ax.nbin for ax in axes])
-    chan = np.arange(0, size)
-    cols = [fits.Column('CHANNEL', 'I', array=chan), ]
     axes_ctr = np.meshgrid(*[ax.center for ax in axes])
     axes_min = np.meshgrid(*[ax.edges[:-1] for ax in axes])
     axes_max = np.meshgrid(*[ax.edges[1:] for ax in axes])
+
     for i, (ax, name) in enumerate(zip(axes, axis_names)):
 
-        names = colname.get(name.lower(),
-                            ['AXIS%i' % i,
-                             'AXIS%i_MIN' % i, 'AXIS%i_MAX' % i])
-        for t, v in zip(names, [axes_ctr, axes_min, axes_max]):
+        if name == 'ENERGY':
+            colnames = ['ENERGY', 'E_MIN', 'E_MAX']
+        elif name == 'TIME':
+            colnames = ['TIME', 'T_MIN', 'T_MAX']
+        else:
+            s = 'AXIS%i' % i if name == '' else name
+            colnames = [s, s + '_MIN', s + '_MAX']
+
+        for colname, v in zip(colnames, [axes_ctr, axes_min, axes_max]):
             array = np.ravel(v[i])
             unit = ax.unit.to_string()
-            cols.append(fits.Column(t, 'E', array=array, unit=unit))
+            cols.append(fits.Column(colname, 'E', array=array, unit=unit))
 
     return cols
 

gammapy/maps/tests/test_wcsnd.py

@@ -17,7 +17,7 @@
 pytest.importorskip('scipy')
 pytest.importorskip('reproject')
 
-axes1 = [MapAxis(np.logspace(0., 3., 3), interp='log')]
+axes1 = [MapAxis(np.logspace(0., 3., 3), interp='log', name='spam')]
 axes2 = [MapAxis(np.logspace(0., 3., 3), interp='log'),
          MapAxis(np.logspace(1., 3., 4), interp='lin')]
 skydir = SkyCoord(110., 75.0, unit='deg', frame='icrs')