Unsure if this is sane

sunpy/map/mapbase.py

@@ -29,7 +29,7 @@
 from astropy.coordinates import BaseCoordinateFrame, Longitude, SkyCoord, UnitSphericalRepresentation
 from astropy.nddata import NDData
 from astropy.utils.metadata import MetaData
-from astropy.visualization import AsymmetricPercentileInterval, HistEqStretch, ImageNormalize
+from astropy.visualization import HistEqStretch, ImageNormalize
 from astropy.visualization.wcsaxes import Quadrangle, WCSAxes
 
 # The next two are not used but are called to register functions with external modules
@@ -43,6 +43,7 @@
 from sunpy.image.resample import resample as sunpy_image_resample
 from sunpy.image.resample import reshape_image_to_4d_superpixel
 from sunpy.image.transform import _get_transform_method, _rotation_function_names, affine_transform
+from sunpy.map.maputils import _clip_interval, _handle_norm
 from sunpy.sun import constants
 from sunpy.time import is_time, parse_time
 from sunpy.util import MetaDict, expand_list
@@ -2534,27 +2535,12 @@ def plot(self, annotate=True, axes=None, title=True, autoalign=False,
         imshow_args.update(copy.deepcopy(imshow_kwargs))
 
         if clip_interval is not None:
-            if len(clip_interval) == 2:
-                clip_percentages = clip_interval.to('%').value
-                vmin, vmax = AsymmetricPercentileInterval(*clip_percentages).get_limits(self.data)
-            else:
-                raise ValueError("Clip percentile interval must be specified as two numbers.")
-
+            vmin, vmax = _clip_interval(self.data, clip_interval)
             imshow_args['vmin'] = vmin
             imshow_args['vmax'] = vmax
 
-        msg = ('Cannot manually specify {0}, as the norm '
-               'already has {0} set. To prevent this error set {0} on '
-               '`m.plot_settings["norm"]` or the norm passed to `m.plot`.')
-        if (norm := imshow_args.get('norm', None)) is not None:
-            if 'vmin' in imshow_args:
-                if norm.vmin is not None:
-                    raise ValueError(msg.format('vmin'))
-                norm.vmin = imshow_args.pop('vmin')
-            if 'vmax' in imshow_args:
-                if norm.vmax is not None:
-                    raise ValueError(msg.format('vmax'))
-                norm.vmax = imshow_args.pop('vmax')
+        if norm:= imshow_args.get('norm', None) is not None:
+            _handle_norm(norm, imshow_args)
 
         if self.mask is None:
             data = self.data

sunpy/map/mapsequence.py

@@ -11,9 +11,9 @@
 import numpy.ma as ma
 
 import astropy.units as u
-from astropy.visualization import AsymmetricPercentileInterval
 
 from sunpy.map import GenericMap
+from sunpy.map.maputils import _clip_interval, _handle_norm
 from sunpy.util import expand_list
 from sunpy.util.exceptions import warn_user
 from sunpy.visualization import axis_labels_from_ctype, wcsaxes_compat
@@ -282,7 +282,6 @@ def plot(self, axes=None, resample=None, annotate=True,
             Color map to be used in coloring the plot.
             This will override the predefined value in ``plot_settings['cmap']``.
 
-
         Returns
         -------
         `matplotlib.animation.FuncAnimation`
@@ -363,33 +362,15 @@ def updatefig(i, im, annotate, ani_data, removes):
 
             im.set_array(ani_data[i].data)
             im.set_cmap(kwargs.get('cmap', ani_data[i].plot_settings['cmap']))
-
             norm = deepcopy(kwargs.get('norm', ani_data[i].plot_settings['norm']))
 
             if clip_interval is not None:
-                if len(clip_interval) == 2:
-                    clip_percentages = clip_interval.to('%').value
-                    vmin, vmax = AsymmetricPercentileInterval(*clip_percentages).get_limits(ani_data[i].data)
-                else:
-                    raise ValueError("Clip percentile interval must be specified as two numbers.")
-
+                vmin, vmax = _clip_interval(self.data, clip_interval)
                 norm.vmin=vmin
                 norm.vmax=vmax
+            _handle_norm(norm, kwargs)
 
-            msg = ('Cannot manually specify {0}, as the norm '
-                   'already has {0} set. To prevent this error set {0} on '
-                   '`m.plot_settings["norm"]` or the norm passed to `m.plot`.')
-            if 'vmin' in kwargs:
-                if norm.vmin is not None:
-                    raise ValueError(msg.format('vmin'))
-                norm.vmin = kwargs.get('vmin')
-            if 'vmax' in kwargs:
-                if norm.vmax is not None:
-                    raise ValueError(msg.format('vmax'))
-                norm.vmax = kwargs.get('vmax')
-
-            # The following explicit call is for bugged versions of Astropy's
-            # ImageNormalize
+            # The following explicit call is for bugged versions of Astropy's ImageNormalize
             norm.autoscale_None(ani_data[i].data)
             im.set_norm(norm)
 

sunpy/map/maputils.py

@@ -8,6 +8,7 @@
 
 import astropy.units as u
 from astropy.coordinates import SkyCoord
+from astropy.visualization import AsymmetricPercentileInterval
 
 from sunpy.coordinates import Helioprojective, sun
 
@@ -20,6 +21,33 @@
            'contains_coordinate', 'contains_solar_center',
            'pixelate_coord_path']
 
+def _clip_interval(data, clip_interval):
+    """
+    Just a helper function to check the input and return the clip interval.
+    Avoids some code duplication.
+    """
+    if len(clip_interval) != 2:
+        raise ValueError("Clip percentile interval must be specified as two numbers.")
+    clip_percentages = clip_interval.to('%').value
+    vmin, vmax = AsymmetricPercentileInterval(*clip_percentages).get_limits(data)
+    return vmin, vmax
+
+def _handle_norm(norm, imshow_args):
+    """
+    Just a helper function to handle the norm of a map or map sequence.
+    Avoids some code duplication.
+    """
+    msg = ('Cannot manually specify {0}, as the norm '
+            'already has {0} set. To prevent this error set {0} on '
+            '`m.plot_settings["norm"]` or the norm passed to `m.plot`.')
+    if 'vmin' in imshow_args:
+        if norm.vmin is not None:
+            raise ValueError(msg.format('vmin'))
+        norm.vmin = imshow_args.pop('vmin')
+    if 'vmax' in imshow_args:
+        if norm.vmax is not None:
+            raise ValueError(msg.format('vmax'))
+        norm.vmax = imshow_args.pop('vmax')
 
 def all_pixel_indices_from_map(smap):
     """