from astropy.io import ascii data = ascii.read("sources.dat") print(data) import numpy as np from astropy.io import ascii from astropy.table import Table data = Table() data["x"] = np.array([1, 2, 3], dtype=np.int32) data["y"] = data["x"] ** 2 ascii.write(data, "values.dat", overwrite=True) data.write("values.ecsv", overwrite=True) # https://docs.astropy.org/en/latest/io/ascii/index.html