Somehow able to generate unstable pole
Need to figure out how the unstable pole is getting generated. Can currently be created for dataset
python -m IIRrational.v2 ~/projects/iirrational/IIRrational_test_data/data/OplevPlant.mat --data_group ap.iy -Xc plant -F ff '' --mode rational --choose shell --never_unstable_poles --never_unstable_zeros