diff --git a/notes_tools/tools/marks_plottings.py b/notes_tools/tools/marks_plottings.py
index 97f4cf5..e3e7d22 100644
--- a/notes_tools/tools/marks_plottings.py
+++ b/notes_tools/tools/marks_plottings.py
@@ -30,7 +30,7 @@ def marks_hist(df):
     :param df: Dataframe with "Mark" and "Bareme" columns. If it has "Nom" column, it is use in title.
     """
     bareme = df["Bareme"].max()
-    bins = bareme*2
+    bins = int(bareme*2)
 
     ax = df["Mark"].hist(bins = bins, range=(0,bareme))