Example Filter Conditions¶

Return Galaxies¶

…below a redshift of 0.1:

nsa.z < 0.1

…on plates 7815 and 8485:

cube.plate == 7815 or cube.plate == 8485

…with a IFU size of 127:

ifu.name = 127*

…with g-r color < 0.2:

g_r < 0.2

…with Halpha flux > 25 in more than 20% of their good spaxels:

npergood(emline_gflux_ha_6564 > 25) >= 20

Return Spaxels¶

…that have an Halpha flux > 25:

emline_gflux_ha_6564 > 25

…that have Halpha EW > 6 in galaxies between stellar mass 9.5-11 with sersic index < 2:

nsa.sersic_logmass >= 9.5 and nsa.sersic_logmass < 11 and nsa.sersic_n < 2 and emline_sew_ha_6564 > 6

…that have NII/Halpha ratio > 0.1:

nii_to_ha > 0.1

Benchmark Queries¶

1. emline_gflux_ha_6564 > 25
2. npergood(spaxelprop.emline_gflux_ha_6564 > 5) >= 20
3. nsa.sersic_logmass >= 9.5 and nsa.sersic_logmass < 11 and nsa.sersic_n < 2 and emline_sew_ha_6564 > 6
4. nsa.z < 0.1 and haflux > 25

Benchmark Remote Query Timing in Marvin¶

Query timing exercise post postgres 9.3 config optimization. From a laptop in Baltimore to Utah with explicit queries in remote mode

q = Query(searchfilter=p, mode='remote')

# Best of 5 (1 loop)
%timeit -n 1 -r 5 r = q.run()

# Best of 5 (10 loops)
%timeit -n 10 -r 5 r = q.run()

Benchmark Query Timing Using Raw SQL¶

Query timing from pasting the raw SQL into psql at Utah, pre postgres 9.6 config optimization.

Query timing from pasting the raw SQL into psql at Utah, post postgres 9.6 config optimization + parallel queries