Hey there, I’m getting into some problems that I don’t know how to solve. This is my code, which is supposed to be a gamma distribution:

```
defnp gamma_nx(x) do
g = 7
p = Nx.tensor([
0.99999999999980993,
676.5203681218851,
-1259.1392167224028,
771.32342877765313,
-176.61502916214059,
12.507343278686905,
-0.13857109526572012,
9.9843695780195716e-6,
1.5056327351493116e-7
])
if x < 0.5 do
pi() / (Nx.sin(pi() * x)) * gamma_nx(1 - x))
else
z = x - 1
xs = while acc = 0.0, i <- Nx.linspace(1, 8, n: 8, type: :u8), unroll: true do
acc + p[i] / (z + i)
end
x = p[0] + xs
t = z + g + 0.5
Nx.sqrt(2 * pi()) * Nx.pow(t, z + 0.5) * Nx.exp(- 1 * t) * x
end
end
```

It works as expected until it gets to gamma_nx; it does not return anything, not even an error message. Can someone help me?