diff --git a/README.md b/README.md
index 306389f..630038c 100644
--- a/README.md
+++ b/README.md
@@ -12,13 +12,15 @@ How to use:
   - The generation of correlation matrix for point spread functions is slow. You can download the correlation matrices prepared by us and put them under the data folder. The correlation matrices are available at: 
   
     https://drive.google.com/file/d/1W5yyXiPQSKssIwIdsIMofBN7eZ9nuApx/view?usp=sharing
-    
-The code is tested with the following environment: 
+
+The code with simulator_old.py is tested with the following environment: 
   - Python      3.6
   - Pytorch     1.4.0
   - Numpy	    1.19.2
   - Scipy       1.6.0
   - Matplotlib  3.3.6
+  
+Update: we modify the code to work with pytorch 1.10 and beyond. Please use simulator.py. Nothing else has changed. 
 
 If you find our work helpful in your research, please consider cite our paper