Added two methods to find the index / indices for the min and max value of a list

src/underscore.py

@@ -362,6 +362,54 @@ def min(self):
             return self._wrap(list())
         return self._wrap(min(self.obj))
 
+    def list_min_index_value(self):
+        """
+            Given a list, returns the index which has the minimum value, along with the value.
+            It assumes the values are comparable objects eg integers, strings, objects that implement __cmp__
+            :param values_list: A list to be searched upon
+            :return: A list of index(es) that have the minimum value
+        """
+
+        if len(self.obj) == 0:
+            return self._wrap([])
+
+        min_value = min(self.obj)
+        how_many = self.obj.count(min_value)
+        c = -1
+        index_list = []
+        for idx, value in enumerate(self.obj):
+            if value == min_value:
+                index_list.append(idx)
+
+                if len(index_list) > how_many:
+                    break
+
+        return self._wrap(index_list)
+
+    def list_max_index_value(self):
+        """
+            Given a list, returns the index which has the maximum value, along with the value.
+            It assumes the values are comparable objects eg integers, strings, objects that implement __cmp__
+            :param values_list: A list to be searched upon
+            :return: A list of index(es) that have the maximum value
+        """
+
+        if len(self.obj) == 0:
+            return self._wrap([])
+
+        max_value = max(self.obj)
+        how_many = self.obj.count(max_value)
+        index_list = []
+        for idx, value in enumerate(self.obj):
+            if value == max_value:
+                index_list.append(idx)
+
+                if len(index_list) >= how_many:
+                    break
+
+
+        return self._wrap(index_list)
+
     def shuffle(self):
         """ Shuffle an array.
         """

tests/test_arrays.py

@@ -179,6 +179,37 @@ def test_range(self):
                          [0, -1, -2, -3, -4, -5, -6, -7, -8, -9], 'final'
                          ' example in the Python docs')
 
+    def test_min_list(self):
+        res = _([-55, -55, -7, 15, 2, 1, -7, 4]).list_min_index_value()
+        expected = [0, 1]
+        assert res == expected
+
+    def test_min_empty_list(self):
+        res = _([]).list_min_index_value()
+        expected = []
+        assert res == expected
+
+    def test_min_one_value(self):
+        res = _([2, 2, 2, 2]).list_min_index_value()
+        expected = [0, 1, 2, 3]
+        assert res == expected
+
+    def test_max_list(self):
+        res = _([-55, -55, -7, 15, 2, 1, -7, 4]).list_max_index_value()
+        expected = [3]
+        assert res == expected
+
+    def test_max_empty_list(self):
+        res = _([]).list_max_index_value()
+        expected = []
+        assert res == expected
+
+    def test_max_one_value(self):
+        res = _([2, 2, 2, 2]).list_max_index_value()
+        expected = [0, 1, 2, 3]
+        assert res == expected
+
+
 if __name__ == "__main__":
     print("run these tests by executing `python -m unittest"
           " discover` in unittests folder")