# binary_cubic_coefficients_from_invariants not working? [closed]

I'm trying to use the function `binary_cubic_coefficients_from_invariants`

from `sage.rings.invariants.reconstruction`

. I tried the example at the documentation for Reconstruction of Algebraic Forms (top of page), which works as shown, and produces the cubic form (0, 1, -1, 0) as shown. However, using any other discriminant (other that 0) in the function call produces the same form. So for example

```
sage: binary_cubic_coefficients_from_invariants(4)
(0, 1, -1, 0)
sage: binary_cubic_coefficients_from_invariants(-4)
(0, 1, -1, 0)
sage: binary_cubic_coefficients_from_invariants(108)
(0, 1, -1, 0)
```

I tried in Sage 10.2 for Mac OS x86 and in SageCell, with the same results in both.

Please submit a bugreport at https://github.com/sagemath/sage/issues

Bug report #37933 submitted.