Getting ZeroDivisionError: float division by zero when using pypret_retriever.py on custom data

[gamenerd457]

Hey, I am getting the following error when running pypret_retriever.py on 2d trace data,
/content/pypret/pypret/retrieval/retriever.py:203: RuntimeWarning: invalid value encountered in scalar divide
w2 = self._weights * self._weights
Started retriever 'copra'
Options:
namespace(alpha=0.25, maxiter=300, maxfev=None)
Initial trace error R = nan
Starting retrieval...

---

ZeroDivisionError Traceback (most recent call last)
in <cell line: 0>()
134
135 # Retrieve from the measured data
--> 136 ret.retrieve(measured_data, pulse.spectrum)
137
138 # and print the retrieval results

2 frames
/content/pypret/pypret/retrieval/step_retriever.py in _retrieve_step(self, iteration, En)
131 if gradient_norm > rs.current_max_gradient:
132 rs.current_max_gradient = gradient_norm
--> 133 gamma = Zm / max(rs.current_max_gradient,
134 rs.previous_max_gradient)
135 # update the spectrum

ZeroDivisionError: float division by zero