ENH: add cmap parameter to Evoked.animate_topomap

doc/changes/dev/13756.newfeature.rst

@@ -0,0 +1 @@
+Added ``cmap`` parameter to ``Evoked.animate_topomap`` to allow user-specified colormaps., by :newcontrib:`Hansuja Budhiraja`.

mne/evoked.py

@@ -797,12 +797,13 @@ def animate_topomap(
         ch_type=None,
         times=None,
         frame_rate=None,
+        *,
+        cmap=None,
         butterfly=False,
         blit=True,
         show=True,
         time_unit="s",
         sphere=None,
-        *,
         image_interp=_INTERPOLATION_DEFAULT,
         extrapolate=_EXTRAPOLATE_DEFAULT,
         vmin=None,
@@ -829,6 +830,11 @@ def animate_topomap(
         frame_rate : int | None
             Frame rate for the animation in Hz. If None,
             frame rate = sfreq / 10. Defaults to None.
+        cmap : matplotlib colormap | None
+            Colormap to use. If None, 'Reds' is used for all positive data,
+            otherwise defaults to 'RdBu_r'.
+
+            .. versionadded:: 1.12.0
         butterfly : bool
             Whether to plot the data as butterfly plot under the topomap.
             Defaults to False.
@@ -880,6 +886,7 @@ def animate_topomap(
             vmin=vmin,
             vmax=vmax,
             verbose=verbose,
+            cmap=cmap,
         )
 
     def as_type(self, ch_type="grad", mode="fast"):

mne/viz/tests/test_topomap.py

@@ -175,12 +175,18 @@ def test_plot_topomap_animation(capsys):
     evoked = read_evokeds(evoked_fname, "Left Auditory", baseline=(None, 0))
 
     # Test animation
-    _, anim = evoked.animate_topomap(
-        ch_type="grad", times=[0, 0.1], butterfly=False, time_unit="s", verbose="debug"
+    fig, anim = evoked.animate_topomap(
+        ch_type="grad",
+        times=[0, 0.1],
+        cmap="viridis",
+        butterfly=False,
+        time_unit="s",
+        verbose="debug",
     )
     anim._func(1)  # _animate has to be tested separately on 'Agg' backend.
     out, _ = capsys.readouterr()
     assert "extrapolation mode local to 0" in out
+    assert fig.axes[0].images[0].get_cmap().name == "viridis"
 
 
 def test_plot_topomap_animation_csd(capsys):

mne/viz/topomap.py

@@ -3149,6 +3149,7 @@ def _init_anim(
     merge_channels,
     sphere,
     ch_type,
+    cmap,
     image_interp,
     extrapolate,
     verbose,
@@ -3174,7 +3175,8 @@ def _init_anim(
 
         data, _ = _merge_ch_data(data, "grad", [])
     norm = True if np.min(data) > 0 else False
-    cmap = "Reds" if norm else "RdBu_r"
+    if cmap is None:
+        cmap = "Reds" if norm else "RdBu_r"
 
     vmin, vmax = _setup_vmin_vmax(data, vmin, vmax, norm)
 
@@ -3324,6 +3326,7 @@ def _key_press(event, params):
 def _topomap_animation(
     evoked,
     ch_type,
+    cmap,
     times,
     frame_rate,
     butterfly,
@@ -3407,6 +3410,7 @@ def _topomap_animation(
         merge_channels=merge_channels,
         sphere=sphere,
         ch_type=ch_type,
+        cmap=cmap,
         image_interp=image_interp,
         extrapolate=extrapolate,
         verbose=verbose,