apps130226_orbit_finder.limit

Test to limit the time when pvat is supported.

''' Test to limit the time when pvat is supported.
'''
import sys

import datetime

import irfpy.cy1orb.pvat2 as pvat

def main():
    '''Main script

    Too slow to be used. Taking 7-8 sec.
    '''

    t0 = datetime.datetime(2010, 1, 1, 0) # Much after CY1 project.
    t1 = datetime.datetime(2008, 1, 1, 0)  # Much before CY1 project.    

    tc = datetime.datetime(2009, 4, 1, 0)  # Inside the CY1 project.

    try:
        pvat.getlsepos(tc)
    except RuntimeError as e:
        print('Failed to load the data.  Please fix as pvat2 works.', file=sys.stderr)
        print(e, file=sys.stderr)
        sys.exit(-1)

    dtlim = datetime.timedelta(microseconds=100000)

    ### Max date available
    tup = t0
    tdn = tc
    dt = tup - tdn

    while dt > dtlim:
        texam = tdn + dt / 2
#        print tup, tdn, texam, dt
        try:
            pvat.getlsepos(texam)
        except (RuntimeError, IOError) as e:
            tup = texam
        else:
            tdn = texam

        dt = tup - tdn

    tmax = tdn

    ### Min date available
    tup = tc
    tdn = t1
    dt = tup - tdn
    while dt > dtlim:
        texam = tdn + dt / 2
#        print tup, tdn, texam, dt
        try:
            pvat.getlsepos(texam)
        except (RuntimeError, IOError) as e:
            tdn = texam
        else:
            tup = texam

        dt = tup - tdn

    tmin = tup

    return tmin, tmax

def main2():
    ''' The second idea of retrieving start/stop datetime of pvat data.

    Acceptable ~1s time scale. It is now used as :func:`irfpy.util.pvat2.getdatarange`.
    '''
    import urllib.request, urllib.parse, urllib.error
    import irfpy.util.irfpyrc
    import irfpy.util.utc
    import irfpy.util.julday
    import irfpy.cy1orb.Cy1Orbit

    rc = irfpy.util.irfpyrc.Rc()

    path = rc.get('cy1orb', 'pvatbase')
    print(path)

    i = 0

    while i < 10000:   # At a certain point, you have to be stopped.
        try:
            uri = path + '/pvat_%04d.gz' % i
            urllib.request.urlretrieve(uri)
        except:
            i += 1
            continue
        print('First orbit is %d' % i)
        oi = irfpy.cy1orb.Cy1Orbit.Cy1Orbit()
        t0 = oi.getPosOfOrb(i)[0, 0]
        print(t0)
        t0 = irfpy.util.utc.convert(irfpy.util.julday.Julday(t0), datetime.datetime)
        print(t0)
        
        break

    while i < 10000:
        try:
            uri = path + '/pvat_%04d.gz' % i
            urllib.request.urlretrieve(uri)
        except:
            print('Last orbit is %d' % (i - 1))
            oi = irfpy.cy1orb.Cy1Orbit.Cy1Orbit()
            t1 = oi.getPosOfOrb(i - 1)[0, -1]
            print(t1)
            t1 = irfpy.util.utc.convert(irfpy.util.julday.Julday(t1), datetime.datetime)
            print(t1)

            break
        else:
            i += 1
        

    return t0, t1

    

if __name__ == "__main__":
    print(main2())