Using the nexsciTAP Server with the PyVO Client to Access KPF Data At KOA In Synchronous Mode

The nexsciTAP server

The NASA Exoplanet Science Institute (NExScI) (visit https://nexsci.caltech.edu) has developed a Python-based server to implement an API that complies with the Virtual Observatory (VO) Table Access Protocol(TAP) version 1.1 (September 2019) (http://ivoa.net/documents/TAP/20190927/index.html), a standard recommended by the International Virtual Observatory alliance (IVOA) (http://ivoa.net).

The TAP API enables a rich variety of searches against tabular data, includung cone, box or all-sky searches, temporal searches, combinations of spatial searches and temporal searches, searches against instrumental attributes and program attributes.

This tutorial supports demonstrates how to use the PyVO client to perform ssynchronous TAP-based queries for public raw science and calibation data acquired with the Keck Planet Finder (KPF) these data are hosted at the Keck Observatory Archive (KOA; https://koa.ipac.caltech.edu).

KPF entered shared-risk usage at the W. M. Keck Observatory in February 2023. Calibration data are immediately made public, and are accessible anonymously through PyKOA. Science data are protected and accessible only by PIs until August 202

Only calibration data are public as May 2023, and the queries shown here will return only calibration files until science data are released no earlier than November 2023 (approximately).

The number of records returned by each query may differ from the number returned in this Notebook because new data are made public daily

Requirements

This tutorial uses PyVO version 1.1.1, and can be installed from PyPI:

$ pip install --upgrade PyVO

The tutorial requires Python 3.6 (or later), plus the table read and write functions from Astropy. We have tested with Astropy 4.0.1, but any version should work. We recommend using the Ananconda Python distribution.

A note on output records

The number of records returned here may differ from those returned here because new data are released daily.

Version 1.0 (June 2023)

Set up

from pyvo.dal import tap 
koa = tap.TAPService("https://koa.ipac.caltech.edu/TAP")
import time

import sys
import os
import time

Query by date

sql = "select koaid, filehand from koa_kpf where koaid like '%20230203%'"
results= koa.run_sync(sql)
print(results)


# write results to VOTable format
table=results.to_table()
table.write ('./table_ipacascii.vot',format='ascii.ipac',overwrite=True)

<Table length=176>
          koaid                                filehand                    
          object                                object                     
------------------------- -------------------------------------------------
KP.20230203.04645.81.fits /KPF/2023/20230203/lev0/KP.20230203.04645.81.fits
KP.20230203.04707.10.fits /KPF/2023/20230203/lev0/KP.20230203.04707.10.fits
KP.20230203.04768.58.fits /KPF/2023/20230203/lev0/KP.20230203.04768.58.fits
KP.20230203.04829.85.fits /KPF/2023/20230203/lev0/KP.20230203.04829.85.fits
KP.20230203.04891.27.fits /KPF/2023/20230203/lev0/KP.20230203.04891.27.fits
KP.20230203.04952.81.fits /KPF/2023/20230203/lev0/KP.20230203.04952.81.fits
KP.20230203.05013.97.fits /KPF/2023/20230203/lev0/KP.20230203.05013.97.fits
KP.20230203.05075.24.fits /KPF/2023/20230203/lev0/KP.20230203.05075.24.fits
KP.20230203.05136.75.fits /KPF/2023/20230203/lev0/KP.20230203.05136.75.fits
KP.20230203.05198.15.fits /KPF/2023/20230203/lev0/KP.20230203.05198.15.fits
                      ...                                               ...
KP.20230203.71589.50.fits /KPF/2023/20230203/lev0/KP.20230203.71589.50.fits
KP.20230203.71687.88.fits /KPF/2023/20230203/lev0/KP.20230203.71687.88.fits
KP.20230203.71950.07.fits /KPF/2023/20230203/lev0/KP.20230203.71950.07.fits
KP.20230203.72212.26.fits /KPF/2023/20230203/lev0/KP.20230203.72212.26.fits
KP.20230203.74273.23.fits /KPF/2023/20230203/lev0/KP.20230203.74273.23.fits
KP.20230203.74342.62.fits /KPF/2023/20230203/lev0/KP.20230203.74342.62.fits
KP.20230203.74412.34.fits /KPF/2023/20230203/lev0/KP.20230203.74412.34.fits
KP.20230203.74611.03.fits /KPF/2023/20230203/lev0/KP.20230203.74611.03.fits
KP.20230203.74681.56.fits /KPF/2023/20230203/lev0/KP.20230203.74681.56.fits
KP.20230203.74752.55.fits /KPF/2023/20230203/lev0/KP.20230203.74752.55.fits

PyVO by default returns results in VOTable format. You can also write to IPAC ASCII and CSV format for storage.

# write results to an IPAC ASCII table
sql = "select koaid, filehand from koa_kpf where koaid like '%20230203%' "
results = koa.run_sync(sql)
table=results.to_table()
table.write ('./table_ipacascii.tbl',format='ascii.ipac',overwrite=True)

#  write results to CSV file
sql = "select koaid, filehand from koa_kpf where koaid like '%20230203%' "
results = koa.run_sync(sql)
table=results.to_table()
table.write ('./table_csv.csv',format='csv', overwrite=True)

Select all keywords for data acquired on UT Date

sql = "select * from koa_kpf where koaid like '%20230203%' "
results = koa.run_sync(sql)
print (results)

## write to an output file
table_selectall=results.to_table()
table_selectall.write ('./table_selectall.vot',format='votable',overwrite=True)

<Table length=176>
          koaid           propint koaimtyp ...     y        z      spt_ind 
                                           ...                             
          object           int32   object  ...  float64  float64    int32  
------------------------- ------- -------- ... --------- -------- ---------
KP.20230203.04645.81.fits       0     bias ... -0.358368 0.000675 200020012
KP.20230203.04707.10.fits       0     bias ... -0.358368 0.000675 200020012
KP.20230203.04768.58.fits       0     bias ... -0.358368 0.000675 200020012
KP.20230203.04829.85.fits       0     bias ... -0.358368 0.000675 200020012
KP.20230203.04891.27.fits       0     bias ... -0.358368 0.000675 200020012
KP.20230203.04952.81.fits       0     bias ... -0.358368 0.000675 200020012
KP.20230203.05013.97.fits       0     bias ... -0.358368 0.000675 200020012
KP.20230203.05075.24.fits       0     bias ... -0.358368 0.000675 200020012
KP.20230203.05136.75.fits       0     bias ... -0.358368 0.000675 200020012
                      ...     ...      ... ...       ...      ...       ...
KP.20230203.71589.50.fits       0  arclamp ... -0.358368 0.000675 200020012
KP.20230203.71687.88.fits       0  arclamp ... -0.358368 0.000675 200020012
KP.20230203.71950.07.fits       0  arclamp ... -0.358368 0.000675 200020012
KP.20230203.72212.26.fits       0  arclamp ... -0.358368 0.000675 200020012
KP.20230203.74273.23.fits       0 flatlamp ... -0.358368 0.000675 200020012
KP.20230203.74342.62.fits       0 flatlamp ... -0.358368 0.000675 200020012
KP.20230203.74412.34.fits       0 flatlamp ... -0.358368 0.000675 200020012
KP.20230203.74611.03.fits       0  arclamp ... -0.358368 0.000675 200020012
KP.20230203.74681.56.fits       0  arclamp ... -0.358368 0.000675 200020012
KP.20230203.74752.55.fits       0  arclamp ... -0.358368 0.000675 200020012

WARNING: W50: ?:?:?: W50: Invalid unit string 'pixels' [astropy.io.votable.tree]
WARNING: W50: ?:?:?: W50: Invalid unit string 'arcseconds' [astropy.io.votable.tree]
WARNING: W50: ?:?:?: W50: Invalid unit string 'degrees' [astropy.io.votable.tree]
WARNING: W50: ?:?:?: W50: Invalid unit string 'e/Dn' [astropy.io.votable.tree]
WARNING: W50: ?:?:?: W50: Invalid unit string 'arcseconds/s' [astropy.io.votable.tree]
WARNING: W50: ?:?:?: W50: Invalid unit string 'Celsius' [astropy.io.votable.tree]

Select columns acquired on UT date

sql = "select koaid, filehand, imtype  from koa_kpf where koaid like '%20230203%'"
results = koa.run_sync(sql)
print (results)

table   = results.to_table()
table.write('./select_columns.vot',format='ascii.ipac',overwrite=True)

<Table length=176>
          koaid           ...  imtype 
          object          ...  object 
------------------------- ... --------
KP.20230203.04645.81.fits ...     Bias
KP.20230203.04707.10.fits ...     Bias
KP.20230203.04768.58.fits ...     Bias
KP.20230203.04829.85.fits ...     Bias
KP.20230203.04891.27.fits ...     Bias
KP.20230203.04952.81.fits ...     Bias
KP.20230203.05013.97.fits ...     Bias
KP.20230203.05075.24.fits ...     Bias
KP.20230203.05136.75.fits ...     Bias
KP.20230203.05198.15.fits ...     Bias
                      ... ...      ...
KP.20230203.71589.50.fits ...  Arclamp
KP.20230203.71687.88.fits ...  Arclamp
KP.20230203.71950.07.fits ...  Arclamp
KP.20230203.72212.26.fits ...  Arclamp
KP.20230203.74273.23.fits ... Flatlamp
KP.20230203.74342.62.fits ... Flatlamp
KP.20230203.74412.34.fits ... Flatlamp
KP.20230203.74611.03.fits ...  Arclamp
KP.20230203.74681.56.fits ...  Arclamp
KP.20230203.74752.55.fits ...  Arclamp

Select maximum number of records to return from a query

The return message from PyVO can be disregarded

sql="select koaid, filehand, frameno from koa_kpf \
    where koaid like '%20230203%'"
results = koa.run_sync(sql, maxrec=5)
print (results)

table   = results.to_table()
table.write('./select_maxrec.tbl',format='ascii.ipac',overwrite=True)

<Table length=5>
          koaid           ... frameno
          object          ...  int32 
------------------------- ... -------
KP.20230203.04645.81.fits ...   29404
KP.20230203.04707.10.fits ...   29405
KP.20230203.04768.58.fits ...   29406
KP.20230203.04829.85.fits ...   29407
KP.20230203.04891.27.fits ...   29408

Select records by date range

sql="select koaid, filehand from koa_kpf  \
     where (utdatetime >= to_date('2023-02-03 00:00:00', \
    'yyyy-mm-dd HH24:MI:SS') and \
     utdatetime <= to_date('2023-02-04 23:59:59', 'yyyy-mm-dd HH24:MI:SS'))"
results  = koa.run_sync(sql)

print (results)

table_daterange=results.to_table()
table.write ('./table_daterange.vot',format='votable',overwrite=True)

<Table length=355>
          koaid                                filehand                    
          object                                object                     
------------------------- -------------------------------------------------
KP.20230203.04645.81.fits /KPF/2023/20230203/lev0/KP.20230203.04645.81.fits
KP.20230203.04707.10.fits /KPF/2023/20230203/lev0/KP.20230203.04707.10.fits
KP.20230203.04768.58.fits /KPF/2023/20230203/lev0/KP.20230203.04768.58.fits
KP.20230203.04829.85.fits /KPF/2023/20230203/lev0/KP.20230203.04829.85.fits
KP.20230203.04891.27.fits /KPF/2023/20230203/lev0/KP.20230203.04891.27.fits
KP.20230203.04952.81.fits /KPF/2023/20230203/lev0/KP.20230203.04952.81.fits
KP.20230203.05013.97.fits /KPF/2023/20230203/lev0/KP.20230203.05013.97.fits
KP.20230203.05075.24.fits /KPF/2023/20230203/lev0/KP.20230203.05075.24.fits
KP.20230203.05136.75.fits /KPF/2023/20230203/lev0/KP.20230203.05136.75.fits
KP.20230203.05198.15.fits /KPF/2023/20230203/lev0/KP.20230203.05198.15.fits
                      ...                                               ...
KP.20230204.71583.28.fits /KPF/2023/20230204/lev0/KP.20230204.71583.28.fits
KP.20230204.71680.83.fits /KPF/2023/20230204/lev0/KP.20230204.71680.83.fits
KP.20230204.71942.91.fits /KPF/2023/20230204/lev0/KP.20230204.71942.91.fits
KP.20230204.72205.05.fits /KPF/2023/20230204/lev0/KP.20230204.72205.05.fits
KP.20230204.74268.25.fits /KPF/2023/20230204/lev0/KP.20230204.74268.25.fits
KP.20230204.74338.59.fits /KPF/2023/20230204/lev0/KP.20230204.74338.59.fits
KP.20230204.74408.86.fits /KPF/2023/20230204/lev0/KP.20230204.74408.86.fits
KP.20230204.74551.83.fits /KPF/2023/20230204/lev0/KP.20230204.74551.83.fits
KP.20230204.74621.89.fits /KPF/2023/20230204/lev0/KP.20230204.74621.89.fits
KP.20230204.74690.44.fits /KPF/2023/20230204/lev0/KP.20230204.74690.44.fits

Select records by program ID

sql= ("select koaid, filehand, imtype, ha, az  \
    from koa_kpf where (progid = 'ENG') ")
results  = koa.run_sync(sql)
print (results)

table_progid=results.to_table()
table.write ('./progid.vot',format='votable',overwrite=True)

<Table length=36743>
          koaid           ...    az  
                          ... degrees
          object          ... float64
------------------------- ... -------
KP.20230111.77177.87.fits ...  -74.22
KP.20230111.77910.84.fits ... -124.35
KP.20230111.76444.02.fits ...   -20.0
KP.20230111.78033.13.fits ... -124.35
KP.20230111.77544.02.fits ... -124.35
KP.20230111.77666.50.fits ... -124.35
KP.20230111.77788.75.fits ... -124.35
KP.20230111.78155.23.fits ... -124.35
KP.20230111.77300.07.fits ... -119.51
                      ... ...     ...
KP.20230619.63712.69.fits ... -112.66
KP.20230619.63784.66.fits ... -112.66
KP.20230619.63928.29.fits ... -112.66
KP.20230618.84870.52.fits ...   233.0
KP.20230618.81560.93.fits ...   233.0
KP.20230618.10511.01.fits ...   233.0
KP.20230619.02607.83.fits ...   233.0
KP.20230618.09865.08.fits ...   233.0
KP.20230618.06010.73.fits ...   233.0
KP.20230618.85422.24.fits ...   233.0

Count number of records in date range

sql=("select count(*) from koa_kpf where \
    (utdatetime >= to_date('2023-02-03 00:00:00', 'yyyy-mm-dd HH24:MI:SS') and \
     utdatetime <= to_date('2023-02-04 23:59:59', 'yyyy-mm-dd HH24:MI:SS'))"  )

results = koa.run_sync(sql)
print(results)

<Table length=1>
count(*)
 int32  
--------
     355

Count total number of records

sql="select count(*) as total from koa_kpf"

results = koa.run_sync(sql)
print(results)

<Table length=1>
total
int32
-----
36769

---

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The Keck Observatory Archive (KOA) is a collaboration between the NASA Exoplanet Science Institute (NExScI) and the W. M. Keck Observatory (WMKO). NExScI is sponsored by NASA's Exoplanet Exploration Program, and operated by the California Institute of Technology in coordination with the Jet Propulsion Laboratory (JPL).

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