EXA make path visible in fix_geodesic_path example (#487)

* FIX: make path visible

* EXA some small fixes to plot_geodesic_path

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Co-authored-by: Matteo Visconti di Oleggio Castello <[email protected]>

examples/surface_analyses/plot_geodesic_path.py

@@ -24,6 +24,8 @@
 surfs = [cortex.polyutils.Surface(*d)
          for d in cortex.db.get_surf(subject, "fiducial")]
 numl = surfs[0].pts.shape[0]
+numr = surfs[1].pts.shape[0]
+num_vertices = numl + numr
 
 # Now we need to pick the start and end points of the line we will draw
 pt_a = 100
@@ -33,12 +35,12 @@
 path = surfs[0].geodesic_path(pt_a, pt_b)
 
 # In order to plot this on the cortical surface, we need an array that is the
-# same size as the number of vertices in the left hemisphere
-path_data = np.zeros(numl)
+# same size as the number of vertices
+path_data = np.zeros(num_vertices) * np.nan
 for v in path:
     path_data[v] = 1
 
 # And now plot these distances onto the cortical surface
-path_verts = cortex.Vertex(path_data, subject, cmap="Blues_r")
-cortex.quickshow(path_verts, with_colorbar=False)
+path_verts = cortex.Vertex(path_data, subject, cmap="Reds", vmin=0, vmax=1)
+cortex.quickshow(path_verts, with_colorbar=False, with_curvature=True)
 plt.show()