1 files changed, 29 insertions, 0 deletions
diff --git a/qtip/utils/formula.py b/qtip/utils/formula.py
new file mode 100644
index 00000000..cdfbae86
--- /dev/null
+++ b/qtip/utils/formula.py
@@ -0,0 +1,29 @@
+##############################################################################
+# Copyright (c) 2016 ZTE Corp and others.
+#
+# All rights reserved. This program and the accompanying materials
+# are made available under the terms of the Apache License, Version 2.0
+# which accompanies this distribution, and is available at
+# http://www.apache.org/licenses/LICENSE-2.0
+##############################################################################
+
+import numpy
+
+from qtip.base.error import make_tbd
+from qtip.base.constant import FormulaName
+
+
+MAPPING = {
+    FormulaName.ARITHMETIC_MEAN: numpy.mean,
+    FormulaName.WEIGHTED_ARITHMETIC_MEAN: numpy.average,
+    # TODO(yujunz) find or implement the method
+    FormulaName.GEOMETRIC_MEAN: make_tbd(FormulaName.GEOMETRIC_MEAN, __name__),
+    # TODO(yujunz) find or implement the method
+    FormulaName.WEIGHTED_GEOMETRIC_MEAN:
+        make_tbd(FormulaName.GEOMETRIC_MEAN, __name__)}
+
+
+class Formula:
+    """calculate a score from give data"""
+    def __init__(self, name):
+        self.calculate = MAPPING[name]