MPS._scale_axis_B: use 1./S instead of S**(-1.)

Thanks to Ruben for suggesting this!
tenpy · Mar 11, 2021 · d9821b8 · d9821b8
1 parent 2ed1f59
commit d9821b8
Showing 1 changed file with 3 additions and 1 deletion.
diff --git a/tenpy/networks/mps.py b/tenpy/networks/mps.py
@@ -3363,7 +3363,9 @@ def _scale_axis_B(self, B, S, form_diff, axis_B, cutoff):
             return B  # nothing to do
         if not isinstance(S, npc.Array):
             # the usual case: S is a 1D array with singular values
-            if form_diff != 1.:
+            if form_diff == -1.:
+                S = 1. / S
+            elif form_diff != 1.:
                 S = S**form_diff
             return B.scale_axis(S, axis_B)
         else: