diff --git a/fourcell/analyze.py b/fourcell/analyze.py
index 66cebd1..306f07c 100644
--- a/fourcell/analyze.py
+++ b/fourcell/analyze.py
@@ -94,7 +94,7 @@ while count < 6 :
 			strC = f'{cX},{cY}'
 			if strC in centersStr :
 				continue
-			centers.appendStr(strC)
+			centersStr.append(strC)
 			corners.append((cX, cY))
 			print(f'{cX},{cY}')
 			cv2.circle(img, (cX, cY), 40, (255, 0, 0), -1)