BUG: Raise error in np.einsum_path when multiple output subscripts ar…

…e specified
numpy · Nov 22, 2023 · a891dc9 · a891dc9
1 parent 1166ef8
commit a891dc9
Showing 1 changed file with 3 additions and 0 deletions.
diff --git a/numpy/_core/einsumfunc.py b/numpy/_core/einsumfunc.py
@@ -714,6 +714,9 @@ def _parse_einsum_input(operands):
 
     # Make sure output subscripts are in the input
     for char in output_subscript:
+        if output_subscript.count(char) != 1:
+            raise ValueError("Output character %s appeared more than once in "
+                             "the output." % char)
         if char not in input_subscripts:
             raise ValueError("Output character %s did not appear in the input"
                              % char)