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VSX HTTP GET and search error?

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Meeka
Meeka's picture
VSX HTTP GET and search error?

I've noticed some missing stars in my HTTP GET queries of VSX - if a constellation has less than 9999 stars I get the full set, but if I have to break up my queries into smaller chunks to accomodate larger constellations I get missing stars. I've been breaking up the queries using maxhi and maxlo field ranges so as not to leave any stars out (the field is never null as far as I can tell). However, those queries fail to return any stars where max mag = 0.000. 

For a sanity check, I put the same query parameters into the regular VSX search page and got the same results, missing the stars where max mag = 0.000.

Example: all variable stars in Carina (excluding suspects and nonvariables) If I search using the VSX search page for all variable stars, I get 14372 results. If I break up the search into two searches, one with max mag between -30 and 13.99999 and one with max mag between 14.0 and 1000, I get a total of 14368 results, with either the VSX search page or the HTTP get queries. 

Comparing the two sets of results, I can only tell that the missing stars have mag mag of 0.00 but I thought that would have been caught in the first of the two searches? I feel like there's something I'm missing on this, any help would be greatly appreciated.

wlp
VSX query limits

There is a (rather arbitrary) limit of 9999 records for the HTTP GET query of VSX to prevent huge downloads. 

In Carina there are four variable stars without a maximum magnitude: V0401 Car, V0433 Car, OGLE-GD-DSCT-0006 and OGLE-GD-DSCT-0010.  If you impose limits on the maximum magnitude, those four stars will never satisfy the conditions.  If you want to break up the query, I suggest to do it e.g. by RA or declination.  For real stars coordinates will always be present.

Patrick

Meeka
Meeka's picture
Thanks Patrick, I'll modify

Thanks Patrick, I'll modify my queries to break up by RA or Dec then.

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