changed density to percent of cell

scripts/spatial_network/perlin/paper_figures_spatial_head_direction_network_perlin_map.py

@@ -976,7 +976,7 @@ def plot_hdi_histogram_combined_and_overlayed(traj, plot_run_names, ex_polar_plo
     max_density = 1.2*max_density
     fig.subplots_adjust(left=0.2, right=0.95, bottom=0.2)
 
-    axes[0].annotate('density', (0, 1.0), xycoords='axes fraction', va="bottom", ha="right")
+    axes[0].annotate('% cells', (0, 1.0), xycoords='axes fraction', va="bottom", ha="right")
 
     axes[1].annotate("no ihn.\n{:.2f}".format(no_conn_hdi), xy=(no_conn_hdi, max_density),
                 xytext=(-2, 0), xycoords="data",