diff --git a/notes_tools/tools/bareme.py b/notes_tools/tools/bareme.py
new file mode 100644
index 0000000..c8ba831
--- /dev/null
+++ b/notes_tools/tools/bareme.py
@@ -0,0 +1,68 @@
+#! /usr/bin/env python
+# -*- coding: utf-8 -*-
+# vim:fenc=utf-8
+#
+# Copyright © 2017 lafrite <lafrite@Poivre>
+#
+# Distributed under terms of the MIT license.
+
+"""
+Manipulating rating scale of an evaluation.
+
+Those functions are made to be applied over eval_df
+"""
+
+from .df_marks_manip import round_half_point, compute_mark_barem
+
+__all__ = []
+
+def new_scale_min(x):
+    """ Change the scale by selecting min between scale and mark """
+    return min(x["Mark_old"], x["Bareme"])
+
+def new_scale_proportionnal(x):
+    """ Changing the scale proportionally """
+    return round_half_point(x["Mark_old"] * x["Bareme"] / x["Bareme_old"])
+
+def tranform_scale(eval_df, new_scale, method):
+    """ Change the rating scale of the exam
+
+    It backups Bareme, Mark, Mark_barem columns adding "_old". The backup is done once then it is ignored.
+
+    It changes Bareme value to new_scale, applies method to marks and remake mark_bareme
+
+    :param eval_df: dataframe on evaluations
+    :param new_scale: replacement scale value
+    :param method: "min", "prop" or a function on eval_df rows
+    :returns: the transformed eval_df
+
+    """
+    for c in ["Bareme", "Mark", "Mark_barem"]:
+        try:
+            eval_df[c+"_old"]
+        except KeyError:
+            eval_df[c+"_old"] = eval_df[c]
+
+    eval_df["Bareme"] = new_scale 
+
+    TRANFS = {"min": new_scale_min,
+            "prop": new_scale_proportionnal,
+            }
+    try:
+        t = TRANFS[method]
+    except KeyError:
+        eval_df["Mark"] = eval_df.apply(method)
+    else:
+        eval_df["Mark"] = eval_df.apply(t, axis=1)
+
+    eval_df["Mark_barem"] = compute_mark_barem(eval_df)
+    return eval_df
+
+
+
+
+
+# -----------------------------
+# Reglages pour 'vim'
+# vim:set autoindent expandtab tabstop=4 shiftwidth=4:
+# cursor: 16 del