diff --git a/metrics.py b/metrics.py
index d53c716..82f0c9e 100644
--- a/metrics.py
+++ b/metrics.py
@@ -6,8 +6,9 @@
 import numpy as np
 
 def compute_metrics(x):
-    sx = np.sort(-x, axis=1)
-    d = np.diag(-x)
+    x = -np.concatenate(x, axis=0)
+    sx = np.sort(x, axis=1)
+    d = np.diag(x)
     d = d[:, np.newaxis]
     ind = sx - d
     ind = np.where(ind == 0)