Notebook

Creating a VO Table from a CSV file¶

There are several ways of doing this, and there are a few object layers here, which can be confusing:

Standard astropy Table objects
Votable Table objects
Votable VOTableFile objects (may contain multiple votable Tables)

Although some things can be done with generic astropy Tables, other VO operations can only be done with VO Tables or VOTableFile objects.

This is easiest to see with an example.

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import io, numpy

from astropy import table as aptable
from astropy.io import votable as apvot

Create a table with only two columns starting from an astropy Table¶

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myaptable=aptable.Table(
    numpy.array([
            [19.0186,       46.7304],
            [20.2887,       40.4703],
            [125.886,       21.3377],
            [136.002,       21.9679],
            [141.057,       40.6372],
            [146.700,       22.0116],
            [148.785,       14.2922],
            [149.751,       17.8168],
            [175.039,       15.3270],
            [191.542,       30.7317],
            [194.913,       28.8959],
            [199.026,       41.5011],
            [206.577,       43.8511],
            [209.963,       38.1821],
            [213.556,       15.6214],
            [219.967,       42.7421],
            [226.693,       12.8502],
            [237.489,       20.8057],
            [241.519,       20.8014],
            [317.088,       18.2002],
            [329.235,       6.64845],
            [333.830,       37.3012] ]), 
    names=["RA","DEC"])

print(type(myaptable))
print(myaptable)

Then convert this to a VOTableFile object which contains a nested set of resources and tables (in this case, only one of each)¶

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myvotablefile = apvot.from_table(myaptable)
print(type(myvotablefile))

for r in myvotablefile.resources:
    mytable=r
    for t in r.tables:
        print(t)

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