fixing lumifactor support for overlay_ROC

compare.py

@@ -21,6 +21,7 @@ def overlay_ROC(filename, *projects, **kwargs):
     plot_thresholds = kwargs.pop("plot_thresholds", False)
     threshold_log = kwargs.pop("threshold_log", True)
     lumifactor = kwargs.pop("lumifactor", None)
+    tight_layout = kwargs.pop("tight_layout", False)
     if kwargs:
         raise KeyError("Unknown kwargs: {}".format(kwargs))
 
@@ -57,9 +58,9 @@ def overlay_ROC(filename, *projects, **kwargs):
         if lumifactor is not None:
             sumw_b = p.w_test[p.y_test==0].sum()*lumifactor
             sumw_s = p.w_test[p.y_test==1].sum()*lumifactor
-            ax_abs_b.plot(tpr, (1.-fpr)*sumw_b, "r--", alpha=0.5)
+            ax_abs_b.plot(tpr, (1.-fpr)*sumw_b, alpha=0)
             ax_abs_b.invert_yaxis()
-            ax_abs_s.plot(tpr*sumw_s, fpr, "g--", alpha=0.5)
+            ax_abs_s.plot(tpr*sumw_s, fpr, alpha=0)
 
     if xlim is not None:
         ax.set_xlim(*xlim)
@@ -79,7 +80,7 @@ def overlay_ROC(filename, *projects, **kwargs):
         ax.set_title('Receiver operating characteristic')
     ax.set_ylabel("Background rejection")
     ax.set_xlabel("Signal efficiency")
-    if plot_thresholds:
+    if plot_thresholds or tight_layout:
         # to fit right y-axis description
         fig.tight_layout()
     return save_show(plt, fig, filename)