Fix plotting for cases when spectral_snratio is not defined

Author: claudiodsf

sourcespec/ssp_build_spectra.py

@@ -516,6 +516,7 @@ def _check_spectral_sn_ratio(config, spec, specnoise):
     weight = _build_weight_from_noise(config, spec, specnoise)
     # if no noise window is available, snratio is not computed
     if weight.snratio is None:
+        spec.stats.spectral_snratio = None
         return
     if config.spectral_sn_freq_range is not None:
         sn_fmin, sn_fmax = config.spectral_sn_freq_range

sourcespec/ssp_plot_spectra.py

@@ -438,6 +438,8 @@ def _add_legend(config, plot_params, spec_st, specnoise_st):
 
 def _snratio_text(spec, ax, color, path_effects):
     global snratio_text_ypos
+    if spec.stats.spectral_snratio is None:
+        return
     snratio_text = f'S/N: {spec.stats.spectral_snratio:.1f}'
     ax.text(
         0.95, snratio_text_ypos, snratio_text, ha='right', va='top',