def check_visible(src,aa,t=None,check27m=True,check2m=True):
''' Check whether a source is observable from the location of aa
given the limits on az/el of the 2-m's and HA/dec of the 27-m's, at
date/time dt. Returns True if visible, False otherwise.
If no time is given, it checks for the current time.
By default, returns True only if it is visible from both the 2-m's and the
27-m's; use check27m=False or check2m=False to ignore either the 27-m's or
the 2-m's, respectively.
'''
if t is None:
t = util.Time.now()
# get alt, az, ha, dec at given date/time
aa.set_jultime(t.jd)
src.compute(aa)
alt = rad2deg(src.alt)
az = rad2deg(src.az)
ha = rad2deg(eovsa_ha(src,t))
dec = rad2deg(src.dec)
if check27m and check2m:
return check_27m_visible(ha,dec) and check_2m_visible(az,alt) and check_2meq_visible(ha,dec)
elif check27m:
return check_27m_visible(ha,dec)
elif check2m:
return check_2m_visible(az,alt) and check_2meq_visible(ha,dec)
else:
return True
def check_visible(src, aa, t=None, check27m=True, check2m=True):
''' Check whether a source is observable from the location of aa
given the limits on az/el of the 2-m's and HA/dec of the 27-m's, at
date/time dt. Returns True if visible, False otherwise.
If no time is given, it checks for the current time.
By default, returns True only if it is visible from both the 2-m's and the
27-m's; use check27m=False or check2m=False to ignore either the 27-m's or
the 2-m's, respectively.
'''
if t is None:
t = util.Time.now()
# get alt, az, ha, dec at given date/time
aa.set_jultime(t.jd)
src.compute(aa)
alt = rad2deg(src.alt)
az = rad2deg(src.az)
ha = rad2deg(eovsa_ha(src, t))
dec = rad2deg(src.dec)
if check27m and check2m:
return check_27m_visible(ha, dec) and check_2m_visible(az, alt)
elif check27m:
return check_27m_visible(ha, dec)
elif check2m:
return check_2m_visible(az, alt)
else:
return True
def amphz(out):
bl2ord = ri.p.bl_list()
uv = copy.copy(out['uvw'][:,:,:2])
time = Time(out['time'],format='jd')
# Get some of the other information we need for this source
srclist = ec.load_VLAcals()
cat = aipy.amp.SrcCatalog(srclist)
aa = ea.eovsa_array()
cat.compute(aa)
aa.cat = cat
src = aa.cat[out['source']]
src.name = out['source']
ha = np.zeros(len(time),'double')
for i in range(1,len(time)):
ha[i] = el.eovsa_ha(src,time[i])
# Select only baselines with Ant 14, and eliminate XY and YX polarizations, and the first time
data = out['x'][bl2ord[:13,13],:2,:,1:]
phz = np.angle(data)
a0 = abs(np.sum(data,3)) # Time averaged amplitude
damp = np.std(abs(data),3)
p0 = np.angle(np.sum(data,3)) # Time averaged angle
nbl,npol,nf,nt = data.shape
pdif = np.zeros(data.shape,'float')
for i in range(nt):
pdif[:,:,:,i] = phz[:,:,:,i] - p0
pdif[np.where(pdif > np.pi)] -= 2*np.pi
pdif[np.where(pdif < -np.pi)] += 2*np.pi
dphase = np.std(pdif,3)
outdict = {'amp':a0,'damp':damp,'phase':p0,'dphase':dphase,'time':time,'ha':np.mean(ha),'dec':src.dec,
'fghz':out['fghz'],'source':src,'uv':uv}
return outdict
def bl_phz(bn,be,fghz,times):
''' Initial test routine to play with baseline corrections. This
routine takes a baseline error in N direction, bn, and baseline
error in E direction, be, as well as a list of frequencies and
times corresponding to an actual observation, and returns the
phase error associated with the baseline error. The phase errors
are relative to the phases at the first time, for easy comparison
with "calibrated" phases in actual data.
Usage:
dphz = bl_phz(bn,be,fghz,times)
'''
nf = len(fghz)
nt = len(times)
aa = ea.eovsa_array()
src = aipy.amp.RadioSpecial('Sun')
dphz = np.zeros((nf,nt),'float')
for i,t in enumerate(times):
aa.set_jultime(t.jd)
src.compute(aa)
ha = el.eovsa_ha(src,t)
dec = src.dec
bx = -bn * np.sin(aa.lat)
by = be
bz = bn*np.cos(aa.lat)
dphz[:,i] = 2*np.pi*(bx*np.cos(dec)*np.cos(ha) - by*np.cos(dec)*np.sin(ha) + bz*np.sin(dec))*fghz/0.3
# Normal phases to first time
blah2 = copy.copy(dphz)
for i in range(nt):
blah2[:,i] = blah2[:,i]-dphz[:,0]
dphz = blah2
# Ensure the phases are between -pi and pi
dphz = dphz % (2*np.pi)
dphz[where(dphz > np.pi)] -= 2*np.pi
return dphz
def amphz(out):
bl2ord = ri.p.bl_list()
uv = copy.copy(out['uvw'][:, :, :2])
time = Time(out['time'], format='jd')
# Get some of the other information we need for this source
srclist = ec.load_VLAcals()
cat = aipy.amp.SrcCatalog(srclist)
aa = ea.eovsa_array()
cat.compute(aa)
aa.cat = cat
src = aa.cat[out['source']]
src.name = out['source']
ha = np.zeros(len(time), 'double')
for i in range(1, len(time)):
ha[i] = el.eovsa_ha(src, time[i])
# Select only baselines with Ant 14, and eliminate XY and YX polarizations, and the first time
data = out['x'][bl2ord[:13, 13], :2, :, 1:]
phz = np.angle(data)
a0 = abs(np.sum(data, 3)) # Time averaged amplitude
damp = np.std(abs(data), 3)
p0 = np.angle(np.sum(data, 3)) # Time averaged angle
nbl, npol, nf, nt = data.shape
pdif = np.zeros(data.shape, 'float')
for i in range(nt):
pdif[:, :, :, i] = phz[:, :, :, i] - p0
pdif[np.where(pdif > np.pi)] -= 2 * np.pi
pdif[np.where(pdif < -np.pi)] += 2 * np.pi
dphase = np.std(pdif, 3)
outdict = {
'amp': a0,
'damp': damp,
'phase': p0,
'dphase': dphase,
'time': time,
'ha': np.mean(ha),
'dec': src.dec,
'fghz': out['fghz'],
'source': src,
'uv': uv
}
return outdict
def bl_phz(bn, be, fghz, times):
''' Initial test routine to play with baseline corrections. This
routine takes a baseline error in N direction, bn, and baseline
error in E direction, be, as well as a list of frequencies and
times corresponding to an actual observation, and returns the
phase error associated with the baseline error. The phase errors
are relative to the phases at the first time, for easy comparison
with "calibrated" phases in actual data.
Usage:
dphz = bl_phz(bn,be,fghz,times)
'''
nf = len(fghz)
nt = len(times)
aa = ea.eovsa_array()
src = aipy.amp.RadioSpecial('Sun')
dphz = np.zeros((nf, nt), 'float')
for i, t in enumerate(times):
aa.set_jultime(t.jd)
src.compute(aa)
ha = el.eovsa_ha(src, t)
dec = src.dec
bx = -bn * np.sin(aa.lat)
by = be
bz = bn * np.cos(aa.lat)
dphz[:, i] = 2 * np.pi * (bx * np.cos(dec) * np.cos(ha) -
by * np.cos(dec) * np.sin(ha) +
bz * np.sin(dec)) * fghz / 0.3
# Normal phases to first time
blah2 = copy.copy(dphz)
for i in range(nt):
blah2[:, i] = blah2[:, i] - dphz[:, 0]
dphz = blah2
# Ensure the phases are between -pi and pi
dphz = dphz % (2 * np.pi)
dphz[where(dphz > np.pi)] -= 2 * np.pi
return dphz
def src2dict(out):
import aipy
import eovsa_array
import eovsa_cat
import eovsa_lst
import copy
bl2ord = ri.p.bl_list()
uv = copy.copy(out['uvw'][:,:,:2])
time = Time(out['time'],format='jd')
# Get some of the other information we need for this source
srclist = eovsa_cat.load_VLAcals()
cat = aipy.amp.SrcCatalog(srclist)
aa = eovsa_array.eovsa_array()
cat.compute(aa)
aa.cat = cat
src = aa.cat[out['source']]
src.name = out['source']
ha = np.zeros(len(time),'double')
for i in range(len(time)):
ha[i] = eovsa_lst.eovsa_ha(src,time[i])
phase = np.angle(out['x'][bl2ord[:,13]])
outdict = {'phase':phase,'time':time,'ha':ha,'dec':src.dec,'fghz':out['fghz'],'source':src,'uv':uv}
return outdict