Plots breaking when using a file with multiple instruments

[Kamuish]

Whenever a file has a column indicating the "number" of the instrument, the plot_random_samples and phase_plot break with the following error. There is no impact on normal operations of kima

Traceback (most recent call last):
  File "plot_kima.py", line 12, in <module>
    res.plot_random_samples()
  File "/data/work/amiguel/kima_target_analysis/WG1Andre/venv/lib/python3.8/site-packages/kima/pykima/display.py", line 2504, in plot_random_samples
    model = res.burst_model(sample, tt, model)
  File "/data/work/amiguel/kima_target_analysis/WG1Andre/venv/lib/python3.8/site-packages/kima/pykima/results.py", line 2206, in burst_model
    if self._time_overlaps[0]:
  File "/data/work/amiguel/kima_target_analysis/WG1Andre/venv/lib/python3.8/site-packages/kima/pykima/results.py", line 2428, in _time_overlaps
    t2min, t2max = minmax(self.data.t[self.data.obs == i + 1])
  File "/data/work/amiguel/kima_target_analysis/WG1Andre/venv/lib/python3.8/site-packages/kima/pykima/results.py", line 2414, in minmax
    return x.min(), x.max()
  File "/data/work/amiguel/kima_target_analysis/WG1Andre/venv/lib/python3.8/site-packages/numpy/core/_methods.py", line 45, in _amin
    return umr_minimum(a, axis, None, out, keepdims, initial, where)
ValueError: zero-size array to reduction operation minimum which has no identity

[j-faria]

@Kamuish, do you have a MWE where this error shows up? Or at least the structure of the data file you used?