diff --git a/modules/deeplearning/cnn_cld_frac.py b/modules/deeplearning/cnn_cld_frac.py
index 34ff0e473c432ae97ae4ac7f98925d2fd27d744e..c5ed1565221d9f440f4abdca56005ca626ff0d65 100644
--- a/modules/deeplearning/cnn_cld_frac.py
+++ b/modules/deeplearning/cnn_cld_frac.py
@@ -1040,13 +1040,11 @@ def analyze2(nda_m, nda_i):
 
     for j in range(1, 65):
         for i in range(1, 65):
-            sum = nda_m[j-1:j+2, i-1:i+2]
-            # cf_m[j-1, i-1] = sum/9
-            cf_m[j-1, i-1] = sum
+            sub_3x3 = nda_m[j-1:j+2, i-1:i+2]
+            cf_m[j-1, i-1] = np.sum(sub_3x3)
 
-            sum = nda_i[j*2-1:j*2+3, i*2-1:i*2+3]
-            # cf_i[j-1, i-1] = sum/16
-            cf_i[j-1, i-1] = sum
+            sub_4x4 = nda_i[j*2-1:j*2+3, i*2-1:i*2+3]
+            cf_i[j-1, i-1] = np.sum(sub_4x4)
 
     # cat_0 = cf_m == 0
     # cat_1 = (cf_m >= 0.1) & (cf_m < 0.13)
@@ -1086,6 +1084,8 @@ def analyze2(nda_m, nda_i):
     cf_i[cat_1] = 1
     cf_i[cat_2] = 2
 
+    return cf_m, cf_i
+
 
 if __name__ == "__main__":
     nn = SRCNN()