specutils

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A seemingly unjustified true_divide warning message pops up when normalizing a spectrum:

import warnings
import astropy
import numpy as np
import astropy.units as u
import specutils

# See Issue https://github.com/astropy/specutils/issues/779
warnings.filterwarnings('ignore', category=astropy.utils.exceptions.AstropyDeprecationWarning)

spec = specutils.Spectrum1D(flux=np.random.normal(2.0, 0.01, size=500)*u.erg/u.s, 
                     spectral_axis=np.linspace(1, 1.5, num=500)*u.micron)

spec.flux / np.median(spec.flux) 

:arrow_right: no warning message

whereas making a new Spectrum1D object somehow is attempting to interpolate, which seems unnecessary for division by a scalar:

spec_normalized = spec / np.median(spec.flux) # yes warning message

:arrow_down:

lib/python3.7/site-packages/scipy/interpolate/interpolate.py:2533: RuntimeWarning: invalid value encountered in true_divide
  (grid[i + 1] - grid[i]))