def _test_erfa_conversion(leap, i_f):
i_i, f_i = i_f
assume(0 <= f_i < 1)
if leap:
assume(i_i in leap_sec_days)
else:
assume(i_i not in leap_sec_days)
jd1_in, jd2_in = day_frac(erfa.DJM0 + i_i, f_i)
y, mo, d, f = erfa.jd2cal(jd1_in, jd2_in)
assert 0 < y < 3000
assert 0 < mo <= 12
assert 0 <= d < 32
assert 0 <= f < 1
jd1_temp, jd2_temp = erfa.cal2jd(y, mo, d)
jd1_temp, jd2_temp = day_frac(jd1_temp, jd2_temp) # improve numerics
jd1_temp, jd2_temp = day_frac(jd1_temp, jd2_temp + f)
jd_change = abs((jd1_temp - jd1_in) + (jd2_temp - jd2_in)) * u.day
assert jd_change.to(u.ns) < 1 * u.ns
ft = 24 * f
h = safe_kind_conversion(np.floor(ft), dtype=int)
ft -= h
ft *= 60
m = safe_kind_conversion(np.floor(ft), dtype=int)
ft -= m
ft *= 60
s = ft
assert 0 <= h < 24
assert 0 <= m < 60
assert 0 <= s < 60
jd1, jd2 = erfa.dtf2d("UTC", y, mo, d, h, m, s)
y2, mo2, d2, f2 = erfa.jd2cal(jd1, jd2)
# assert (y, mo, d) == (y2, mo2, d2)
# assert (abs(f2-f)*u.day).to(u.s) < 1*u.ns
assert jd1 == np.floor(jd1) + 0.5
assert 0 <= jd2 < 1
jd1, jd2 = day_frac(jd1, jd2)
jd_change = abs((jd1 - jd1_in) + (jd2 - jd2_in)) * u.day
if leap:
assert jd_change.to(u.s) < 1 * u.s
else:
assert jd_change.to(u.ns) < 2 * u.ns
# assert jd_change.to(u.ns) < 1 * u.ns
return
i_o, f_o = day_frac(jd1 - erfa.DJM0, jd2)
mjd_change = abs((i_o - i_i) + (f_o - f_i)) * u.day
if leap:
assert mjd_change.to(u.s) < 1 * u.s
else:
assert mjd_change.to(u.ns) < 1 * u.ns
def mjds_to_jds_pulsar(mjd1, mjd2):
# To get around leap second issues, first convert to YMD,
# then back to astropy/ERFA-convention jd1,jd2 using the
# ERFA dtf2d() routine which handles leap seconds.
v1, v2 = day_frac(mjd1, mjd2)
(y, mo, d, f) = erfa.jd2cal(erfa.DJM0 + v1, v2)
# Fractional day to HMS. Uses 86400-second day always.
# Seems like there should be a ERFA routine for this..
# There is: erfa.d2tf. Unfortunately it takes a "number of
# digits" argument and returns some kind of bogus
# fractional-part-as-an-integer thing.
# Worse, it fails to provide nanosecond accuracy.
# Good idea, though, because using np.remainder is
# numerically unstable and gives bogus values now
# and then. This is more stable.
f *= 24
h = safe_kind_conversion(np.floor(f), dtype=int)
f -= h
f *= 60
m = safe_kind_conversion(np.floor(f), dtype=int)
f -= m
f *= 60
s = f
return erfa.dtf2d("UTC", y, mo, d, h, m, s)
DY06 = -0.2259 * AS2R / 1000.
# TT (MJD)
DJMJD0, DATE = erfa.cal2jd(IY, IM, ID)
TIME = (60 * (60 * IH + MIN) + SEC) / 86400.
UTC = DATE + TIME
DAT = erfa.dat(IY, IM, ID, TIME)
TAI = UTC + DAT / 86400.
TT = TAI + 32.184 / 86400.
# UT1
TUT = TIME + DUT1 / 86400.
UT1 = DATE + TUT
print("UTC :%4d/%2.2d/%2.2d%3d:%2.2d:%2.2d.%3.3d" %
erfa.d2dtf(3, *erfa.dtf2d(IY, IM, ID, IH, MIN, SEC)))
print("TT = 2400000.5 + %.17f " % TT)
print("UT1 = 2400000.5 + %.17f " % UT1)
print('''
======================================
IAU 1976/1980/1982/1994, equinox based
======================================
''')
# IAU 1976 precession matrix, J2000.0 to date.
RP = erfa.pmat76(DJMJD0, TT)
# IAU 1980 nutation
DP80, DE80 = erfa.nut80(DJMJD0, TT)
# -*- coding: utf-8 -*-
'''example from sofa_ts_c.pdf
'''
from __future__ import print_function
import math
import numpy as np
import erfa
print('''UTC to TT
transform 2010 July 24, 11:18:07.318 (UTC) into Terrestrial Time (TT)
and report it rounded to 1ms precision''')
# encode UTC date and time into internal format
u1, u2 = erfa.dtf2d('utc',
np.array([2010]),
np.array([7]),
np.array([24]),
np.array([11]),
np.array([18]),
np.array([7.318]))
# transform UTC to TAI, then TAI to TT
a1, a2 = erfa.utctai(u1, u2)
t1, t2 = erfa.taitt(a1, a2)
# decode and report the TT
y, m, d, h = erfa.d2dtf('TT', 3, t1, t2)
print("UTC: 2010 July 24, 11:18:07.318")
for i in range(len(y)):
print("TT : %4d/%2.2d/%2.2d, "%(y[i],m[i],d[i]), end =' ')
print("%3d:%2.2d:%2.2d.%3.3d"%tuple(h[i]))
# Ambient pressure (HPa), temperature (C) and rel. humidity (frac).
phpa = np.array([731.0])
tc = np.array([12.8])
rh = np.array([0.59])
# Effective color (microns).
wl = np.array([0.55])
# UTC date
y = np.array([2013], dtype="int32")
m = np.array([4], dtype="int32")
d = np.array([2], dtype="int32")
h = np.array([23], dtype="int32")
mn = np.array([15], dtype="int32")
sec = np.array([43.55])
utc1, utc2 = erfa.dtf2d("UTC", y, m, d, h, mn, sec)
# TT date
tai1, tai2 = erfa.utctai(utc1, utc2)
tt1, tt2 = erfa.taitt(tai1, tai2)
# EOPs: polar motion in radians, UT1-UTC in seconds.
xp = np.array([50.995e-3 * erfa.DAS2R])
yp = np.array([376.723e-3 * erfa.DAS2R])
dut1 = np.array([155.0675e-3])
##print('xp, yp', xp, yp)
# Corrections to IAU 2000A CIP (radians).
dx = 0.269e-3 * erfa.DAS2R
dy = -0.274e-3 * erfa.DAS2R
# Star ICRS RA,Dec (radians).
def strputc(string):
'''parse a utc string and return utc1, utc2'''
Y,m,d,H,M,S,w,y,dst=time.strptime(string, '%Y/%m/%dT%H:%M:%S')
return erfa.dtf2d(Y,m,d,H,M,S)
DX06 = 0.1750 * AS2R/1000.
DY06 = -0.2259 * AS2R/1000.
# TT (MJD)
DJMJD0, DATE = erfa.cal2jd(IY, IM, ID)
TIME = ( 60*(60*IH + MIN) + SEC ) / 86400.
UTC = DATE + TIME
DAT = erfa.dat(IY, IM, ID, TIME)
TAI = UTC + DAT/86400.
TT = TAI + 32.184/86400.
# UT1
TUT = TIME + DUT1/86400.
UT1 = DATE + TUT
print("UTC :%4d/%2.2d/%2.2d%3d:%2.2d:%2.2d.%3.3d"%erfa.d2dtf(3, *erfa.dtf2d(IY, IM, ID, IH, MIN, SEC)))
print("TT = 2400000.5 + %.17f "%TT)
print("UT1 = 2400000.5 + %.17f "%UT1)
print('''
======================================
IAU 1976/1980/1982/1994, equinox based
======================================
''')
# IAU 1976 precession matrix, J2000.0 to date.
RP = erfa.pmat76(DJMJD0, TT)
# IAU 1980 nutation
DP80, DE80 = erfa.nut80(DJMJD0, TT)
# -*- coding: utf-8 -*-
'''SOFA example, from sofa_ts_c.pdf
'''
from __future__ import print_function
import math
import erfa
print('''UTC to TT
transform 2010 July 24, 11:18:07.318 (UTC) into Terrestrial Time (TT)
and report it rounded to 1ms precision''')
# encode UTC date and time into internal format
u1, u2 = erfa.dtf2d(2010, 7, 24, 11, 18, 7.318)
# transform UTC to TAI, then TAI to TT
a1, a2 = erfa.utctai(u1, u2)
t1, t2 = erfa.taitt(a1, a2)
# decode and report the TT
y, m, d, h, mn, sc, f = erfa.d2dtf(3, t1, t2)
print("UTC: 2010 July 24, 11:18:07.318")
print("TT: %4d/%2.2d/%2.2d%3d:%2.2d:%2.2d.%3.3d" % (y, m, d, h, mn, sc, f))
print('=====')
print('''
TAI to UTC
take a time expressed as TAI, encode it into
the internal format and transform it into UTC''')
# encode TAI date and time into internal format
a1, a2 = erfa.dtf2d(2009, 1, 1, 0, 0, 33.7, "TAI")
DX06 = 0.1750 * AS2R/1000.
DY06 = -0.2259 * AS2R/1000.
# TT (MJD)
DJMJD0, DATE = erfa.cal2jd(IY, IM, ID)
TIME = ( 60*(60*IH + MIN) + SEC ) / 86400.
UTC = DATE + TIME
DAT = erfa.dat(IY, IM, ID, TIME)
TAI = UTC + DAT/86400.
TT = TAI + 32.184/86400.
# UT1
TUT = TIME + DUT1/86400.
UT1 = DATE + TUT
_utc = erfa.dtf2d('utc', IY, IM, ID, IH, MIN, SEC)
y,m,d,h = erfa.d2dtf('utc', 3, *_utc)
for i in range(len(y)):
print("UTC :%4d/%2.2d/%2.2d "%(y[i],m[i],d[i]), end='T')
print("%3d:%2.2d:%2.2d.%3.3d"%tuple(h[i]))
for t in TT:
print("TT = 2400000.5 + %.17f "%t)
for t in UT1:
print("UT1 = 2400000.5 + %.17f "%t)
print('''
======================================
IAU 1976/1980/1982/1994, equinox based
======================================
''')
# site longitude, latitude (radians) and height above the geoid (m).
phi = erfa.af2a(-15,57,42.8)
elong = erfa.af2a(-5,41,54.2)
hm = 625.0
# Ambient pressure (HPa), temperature (C) and rel. humidity (frac).
phpa = 952.0
tc = 18.5
rh = 0.83
# Effective color (microns).
wl = 0.55
# UTC date
utc1, utc2 = erfa.dtf2d(2013, 4, 2, 23, 15, 43.55, "UTC")
# TT date
tai1, tai2 = erfa.utctai(utc1, utc2)
tt1, tt2 = erfa.taitt(tai1, tai2)
# EOPs: polar motion in radians, UT1-UTC in seconds.
xp = 50.995e-3 * erfa.DAS2R
yp = 376.723e-3 * erfa.DAS2R
dut1 = 155.0675e-3
##print('xp, yp', xp, yp)
# Corrections to IAU 2000A CIP (radians).
dx = 0.269e-3 * erfa.DAS2R
dy = -0.274e-3 * erfa.DAS2R
# Star ICRS RA,Dec (radians).
# -*- coding: utf-8 -*-
'''SOFA example, from sofa_ts_c.pdf
'''
from __future__ import print_function
import math
import erfa
print('''UTC to TT
transform 2010 July 24, 11:18:07.318 (UTC) into Terrestrial Time (TT)
and report it rounded to 1ms precision''')
# encode UTC date and time into internal format
u1, u2 = erfa.dtf2d(2010,7,24,11,18,7.318)
# transform UTC to TAI, then TAI to TT
a1, a2 = erfa.utctai(u1, u2)
t1, t2 = erfa.taitt(a1, a2)
# decode and report the TT
y, m, d, h, mn, sc, f = erfa.d2dtf(3, t1, t2)
print("UTC: 2010 July 24, 11:18:07.318")
print("TT: %4d/%2.2d/%2.2d%3d:%2.2d:%2.2d.%3.3d"%(y, m, d, h, mn, sc, f))
print('=====')
print('''
TAI to UTC
take a time expressed as TAI, encode it into
the internal format and transform it into UTC''')
# encode TAI date and time into internal format
a1, a2 = erfa.dtf2d(2009,1,1,0,0,33.7, "TAI")
# site longitude, latitude (radians) and height above the geoid (m).
phi = erfa.af2a(-15, 57, 42.8)
elong = erfa.af2a(-5, 41, 54.2)
hm = 625.0
# Ambient pressure (HPa), temperature (C) and rel. humidity (frac).
phpa = 952.0
tc = 18.5
rh = 0.83
# Effective color (microns).
wl = 0.55
# UTC date
utc1, utc2 = erfa.dtf2d(2013, 4, 2, 23, 15, 43.55, "UTC")
# TT date
tai1, tai2 = erfa.utctai(utc1, utc2)
tt1, tt2 = erfa.taitt(tai1, tai2)
# EOPs: polar motion in radians, UT1-UTC in seconds.
xp = 50.995e-3 * erfa.DAS2R
yp = 376.723e-3 * erfa.DAS2R
dut1 = 155.0675e-3
##print('xp, yp', xp, yp)
# Corrections to IAU 2000A CIP (radians).
dx = 0.269e-3 * erfa.DAS2R
dy = -0.274e-3 * erfa.DAS2R
# Star ICRS RA,Dec (radians).
