Specviz get_spectra() call does not return correctly with multiple spectra

[Jdaviz-Triage-Bot]

Reporter: Jesse Averbukh

This is first mentioned by Cami in JDAT-2594. To see the behavior, add two spectra to Specviz, then add multiple subsets. Then run specviz.get_spectra(). The output should imply that the subsets have a spectral axis that starts where the second spectra starts (assuming it is at a higher wavelength). The expected behavior is that the subset has a spectral axis that corresponds to the spectrum it is attached to.

A question for others, what is the expected output when a subset is attached to multiple spectra?

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DISCLAIMER: This issue was autocreated by the Jdaviz Issue Creation Bot on behalf of the reporter. If any information is incorrect, please contact Duy Nguyen

[pllim]

Definitely a bug. I think the Subset tied to the last loaded data overwrote all the previous ones. This is what is getting looped over for a use case with 2 spectra loaded and 1 subset:

for lyr in specviz.app._viewer_store['specviz-0'].layers:
    print(lyr)

BqplotProfileLayerArtist for myfile
BqplotProfileLayerArtist for Spectrum1D
BqplotProfileLayerArtist for Subset 1
BqplotProfileLayerArtist for Subset 1

Personally, I would expect get_spectra to return 4 entries, not 3:

1. First spectrum
2. Second spectrum
3. Subset for first
4. Subset for second

jdaviz/jdaviz/app.py

Line 680 in 9a1d414

data[label] = layer_data

[kecnry]

Ignoring the spectral-axis vs masking potential issue... options for supporting subsets attached to multiple spectra would either be to return nested dictionaries or to have the keys be data_label and data_label:subset_name.

[pllim]

Or do we want Subsets to be returned at all? Aren't Subsets turned into masks? So this should only return 2 entries right?

1. First data with all the subsets turned into mask.
2. Second data with all the subsets turned into mask.

[javerbukh]

I think my current preference is the dictionary approach. It makes more sense to me for get_data_from_viewer("Subset 1") to return something (i.e. a dictionary with the subset mask applied to each data) rather than None.

[stscijgbot-jwql]

This issue is tracked on JIRA as JDAT-2925.

[stscijgbot-jwql]

Comment by Duy Nguyen on JIRA:

NOTICE: A corresponding GitHub issue was automatically created: #1843