Use new colormap registry in matplotlib

typhon/plots/cm/__init__.py

@@ -12,8 +12,7 @@
 
 .. _cmocean: http://matplotlib.org/cmocean/
 """
-from matplotlib.colors import (LinearSegmentedColormap, ListedColormap)
-from matplotlib.cm import register_cmap
+import matplotlib as mpl
 
 from ._cmocean import datad as _cmocean_datad
 from ._cm import datad as _cm_datad
@@ -33,16 +32,16 @@ def _rev_cdict(cdict):
 cmaps = {}
 for (name, data) in datad.items():
     if isinstance(data, dict):
-        cmaps[name] = LinearSegmentedColormap(name, data)
-        cmaps[name + '_r'] = LinearSegmentedColormap(
+        cmaps[name] = mpl.colors.LinearSegmentedColormap(name, data)
+        cmaps[name + '_r'] = mpl.colorsLinearSegmentedColormap(
             name + '_r', _rev_cdict(data))
     elif isinstance(data, list):
-        cmaps[name] = ListedColormap(data, name)
-        cmaps[name + '_r'] = ListedColormap(data[::-1], name + '_r')
+        cmaps[name] = mpl.colors.ListedColormap(data, name)
+        cmaps[name + '_r'] = mpl.colors.ListedColormap(data[::-1], name + '_r')
 
 locals().update(cmaps)
 
 for name, cm in cmaps.items():
-    register_cmap(name, cm)
+    mpl.colormaps.register(cmap=cm, name=name)
 
 __all__ = list(cmaps.keys())

typhon/plots/colors/common.py

@@ -5,9 +5,8 @@
 from functools import lru_cache
 from warnings import warn
 
+import matplotlib as mpl
 import matplotlib.pyplot as plt
-from matplotlib import colors
-from matplotlib.colors import LinearSegmentedColormap
 import numpy as np
 
 from typhon.utils import deprecated
@@ -57,9 +56,9 @@ def cmap2rgba(cmap=None, N=None, interpolate=True):
 
     nlut = N if interpolate else None
 
-    if interpolate and isinstance(cmap, colors.ListedColormap):
+    if interpolate and isinstance(cmap, mpl.colors.ListedColormap):
         # `ListedColormap` does not support lookup table interpolation.
-        cmap = colors.LinearSegmentedColormap.from_list('', cmap.colors)
+        cmap = mpl.colors.LinearSegmentedColormap.from_list('', cmap.colors)
         return cmap(np.linspace(0, 1, N))
 
     return plt.get_cmap(cmap.name, lut=nlut)(np.linspace(0, 1, N))
@@ -71,7 +70,7 @@ def _to_hex(c):
 
     # Convert rgb to hex.
     if ctype is tuple or ctype is np.ndarray or ctype is list:
-        return colors.rgb2hex(c)
+        return mpl.colors.rgb2hex(c)
 
     if ctype is str:
         # If color is already hex, simply return it.
@@ -80,7 +79,7 @@ def _to_hex(c):
             return c
 
         # Convert named color to hex.
-        return colors.cnames[c]
+        return mpl.colors.cnames[c]
 
     raise Exception("Can't handle color of type: {}".format(ctype))
 
@@ -102,8 +101,8 @@ def colors2cmap(*args, name=None):
         raise Exception("Give at least two colors.")
 
     cmap_data = [_to_hex(c) for c in args]
-    cmap = colors.LinearSegmentedColormap.from_list(name, cmap_data)
-    plt.register_cmap(name, cmap)
+    cmap = mpl.colors.LinearSegmentedColormap.from_list(name, cmap_data)
+    mpl.colormaps.register(cmap=cmap, name=name)
 
     return cmap
 
@@ -289,13 +288,13 @@ def cmap_from_act(file, name=None):
     colors = rgb[:ncolors*3].reshape(ncolors, 3) / 255
 
     # Create and register colormap...
-    cmap = LinearSegmentedColormap.from_list(name, colors, N=ncolors)
-    plt.register_cmap(cmap=cmap)  # Register colormap.
+    cmap = mpl.colors.LinearSegmentedColormap.from_list(name, colors, N=ncolors)
+    mpl.colormaps.register(cmap=cmap)  # Register colormap.
 
     # ... and the reversed colormap.
-    cmap_r = LinearSegmentedColormap.from_list(
+    cmap_r = mpl.colors.LinearSegmentedColormap.from_list(
             name + '_r', np.flipud(colors), N=ncolors)
-    plt.register_cmap(cmap=cmap_r)
+    mpl.colormaps.register(cmap=cmap_r)
 
     return cmap
 
@@ -329,13 +328,13 @@ def cmap_from_txt(file, name=None, N=-1, comments='%'):
         raise Exception('RGB value out of range: [0, 1].')
 
     # Create and register colormap...
-    cmap = LinearSegmentedColormap.from_list(name, rgb, N=N)
-    plt.register_cmap(cmap=cmap)
+    cmap = mpl.colors.LinearSegmentedColormap.from_list(name, rgb, N=N)
+    mpl.colormaps.register(cmap=cmap)
 
     # ... and the reversed colormap.
-    cmap_r = LinearSegmentedColormap.from_list(
+    cmap_r = mpl.colors.LinearSegmentedColormap.from_list(
             name + '_r', np.flipud(rgb), N=N)
-    plt.register_cmap(cmap=cmap_r)
+    mpl.colormaps.register(cmap=cmap_r)
 
     return cmap
 

typhon/tests/plots/test_colors.py

@@ -26,6 +26,15 @@ def teardown_method(self):
         """Delete temporary file."""
         os.remove(self.f)
 
+    def test_colors2cmap(self):
+        """Check colors to colormap conversion."""
+        color_list = ["#0000ff", "#ff0000"]
+
+        cmap = colors.colors2cmap(*color_list, name="test_colors2cmap")
+
+        assert mcolors.rgb2hex(cmap(0.0)) == color_list[0]
+        assert mcolors.rgb2hex(cmap(1.0)) == color_list[-1]
+
     def test_cmap2rgba(self):
         """Check colormap to RGB conversion."""
         ref = np.loadtxt(os.path.join(self.ref_dir, 'viridis.txt'),