diff --git a/.gitignore b/.gitignore
index 37c83965c..cf0bd17d2 100644
--- a/.gitignore
+++ b/.gitignore
@@ -69,3 +69,11 @@ samples2/
 datas/*.py
 
 .idea/
+.DS_Store
+backtrader/.DS_Store
+contrib/.DS_Store
+samples/.DS_Store
+/datas
+/samples
+/datas/
+/samples/
diff --git a/backtrader/comminfo.py b/backtrader/comminfo.py
index 6bfd8e015..ece81921c 100644
--- a/backtrader/comminfo.py
+++ b/backtrader/comminfo.py
@@ -177,7 +177,7 @@ def get_margin(self, price):
           - Use param ``automargin`` * ``price`` if ``automargin > 0``
         '''
         if not self.p.automargin:
-            return self.p.margin
+            return price * self.p.margin
 
         elif self.p.automargin < 0:
             return price * self.p.mult
@@ -192,9 +192,9 @@ def get_leverage(self):
     def getsize(self, price, cash):
         '''Returns the needed size to meet a cash operation at a given price'''
         if not self._stocklike:
-            return int(self.p.leverage * (cash // self.get_margin(price)))
+            return self.p.leverage * (cash / self.get_margin(price))
 
-        return int(self.p.leverage * (cash // price))
+        return self.p.leverage * (cash / price)
 
     def getoperationcost(self, size, price):
         '''Returns the needed amount of cash an operation would cost'''