import numpy as np
import pandas as pd

df = pd.DataFrame({"a": [1,2,3], "b": [2,4,6]})
np.min(df)

/home/julia/conda/envs/dask-upstream/lib/python3.9/site-packages/numpy/core/fromnumeric.py:84: FutureWarning: In a future version, DataFrame.min(axis=None) will return a scalar min over the entire DataFrame. To retain the old behavior, use 'frame.min(axis=0)' or just 'frame.min()'
  return reduction(axis=axis, out=out, **passkwargs)

a    1
b    2
dtype: int64