ENH: multiple colors for ica.plot_sources(evokeds)

doc/changes/latest.inc

@@ -63,6 +63,8 @@ Enhancements
 
 - Speed up :meth:`mne.decoding.TimeDelayingRidge.predict` by switching to FFT-based convolution (:gh:`9458` by `Ross Maddox`_)
 
+- Show multiple colors and linestyles for excluded components with :class:`mne.Evoked` in :meth:`mne.preprocessing.ICA.plot_sources` (:gh:`9444` by `Martin Schulz`_)
+
 Bugs
 ~~~~
 - Fix bug with :meth:`mne.Epochs.crop` and :meth:`mne.Evoked.crop` when ``include_tmax=False``, where the last sample was always cut off, even when ``tmax > epo.times[-1]`` (:gh:`9378` **by new contributor** |Jan Sosulski|_)

mne/viz/ica.py

@@ -574,29 +574,29 @@ def _plot_ica_sources_evoked(evoked, picks, exclude, title, show, ica,
             exclude_labels.append(line_label)
         else:
             exclude_labels.append(None)
-
+    label_props = [('k', '-') if lb is None else ('r', '-') for lb in
+                   exclude_labels]
+    styles = ['-', '--', ':', '-.']
     if labels is not None:
-        # compute colors only based on label categories
+        # differentiate categories by linestyle and components by color
+        col_lbs = [it for it in exclude_labels if it is not None]
+        cmap = plt.get_cmap('tab10', len(col_lbs))
         unique_labels = {k.split(' - ')[1] for k in exclude_labels if k}
-        label_colors = plt.cm.rainbow(np.linspace(0, 1, len(unique_labels)))
-        label_colors = dict(zip(unique_labels, label_colors))
-    else:
-        label_colors = {k: 'red' for k in exclude_labels}
+        # Determine up to 4 different styles for n categories
+        cat_styles = dict(zip(unique_labels,
+                              map(lambda ux: styles[int(ux % len(styles))],
+                                  range(len(unique_labels)))))
+        for lb_idx, lb in enumerate(exclude_labels):
+            if lb is not None:
+                color = cmap(col_lbs.index(lb))
+                style = cat_styles[lb[lb.find(' - ') + 3:]]
+                label_props[lb_idx] = (color, style)
 
     for exc_label, ii in zip(exclude_labels, picks):
-        if exc_label is not None:
-            # create look up for color ...
-            if ' - ' in exc_label:
-                key = exc_label.split(' - ')[1]
-            else:
-                key = exc_label
-            color = label_colors[key]
-            # ... but display component number too
-            lines.extend(ax.plot(times, evoked.data[ii].T, picker=True,
-                                 zorder=2, color=color, label=exc_label))
-        else:
-            lines.extend(ax.plot(times, evoked.data[ii].T, picker=True,
-                                 color='k', zorder=1))
+        color, style = label_props[ii]
+        lines.extend(ax.plot(times, evoked.data[ii].T, picker=True,
+                             zorder=2, color=color, linestyle=style,
+                             label=exc_label))
         lines[-1].set_pickradius(3.)
 
     ax.set(title=title, xlim=times[[0, -1]], xlabel='Time (ms)', ylabel='(NA)')

tutorials/preprocessing/40_artifact_correction_ica.py

@@ -618,7 +618,7 @@
 #     This example is computationally intensive, so it might take a few minutes
 #     to complete.
 #
-# Read and preprocess the data. Preprocessing consists of:
+# After reading the data, preprocessing consists of:
 #
 # - MEG channel selection
 # - 1-30 Hz band-pass filter