Using a data processor on level 1 data produces a RuntimeWarning

[wshanks]

Informations

• Qiskit Experiments version: 0.4.0
• Python version: 3.10
• Operating system: Linux

What is the current behavior?

Every time a data processor is used on level 1 data a RuntimeWarning is generated by numpy.

Steps to reproduce the problem

from qiskit_experiments.data_processing import DataProcessor, nodes
processor = DataProcessor("memory", [nodes.MinMaxNormalize()])
processor({"memory": [0, 1, 2]})

This produces

/home/wshanks/.conda/envs/qiskit/lib/python3.10/site-packages/numpy/lib/function_base.py:2411: RuntimeWarning: invalid value encountered in <lambda> (vectorized)
  outputs = ufunc(*inputs)

What is the expected behavior?

As this is standard usage, no warning should be generated.

Suggested solutions

See #1070.

[wshanks]

Closed by #1070