Документ взят из кэша поисковой машины. Адрес оригинального документа : http://www.mrao.cam.ac.uk/~bn204/alma/memo-turb/imagingsim_obit.py Дата изменения: Fri Aug 10 20:17:35 2012 Дата индексирования: Tue Oct 2 11:45:59 2012 Кодировка: Поисковые слова: spirit rover

# Bojan Nikolic ,
#
# Initial version January 2008
#
# Do imaging simulations, using obit

import os, shutil
import re
import pickle

import pyfits
import numpy

import sys
sys.path.append("../obitsim")

import obittools

from imagingsim_utils import UVNameToDirtyBeamName

def DirUVSets(dirin):

"Return the list of uvdata sets to be reduced in directory"

msre=re.compile(r".*\.ms\.fits")
res = []
for fname in os.listdir(dirin):
if msre.match(fname):
res.append( os.path.join(dirin, fname) )

return res


def DirDirtyMaps(dirin,
**kwargs):

"Reduce whole observations to dirty maps"

for fnamein in DirUVSets(dirin):
obittools.DirtyImage( fnamein,
UVNameToDirtyBeamName(fnamein),
**kwargs)

def SwitchedDirDirtyMaps(dirin,
**kwargs):

"Reduce directory of switched observations"

# Need to make it reduce the science target source only
DirDirtyMaps(dirin,
sources=["F1"])


def DirBeamParams(dirin):

"Find bestfitting gaussians to each full set in directory"

res = {}
for fnamein in DirUVSets(dirin):
fbase=os.path.basename(fnamein)
dname=UVNameToDirtyBeamName(fnamein)
res[fbase] = obittools.FitGaussian( os.path.join(dirin, dname))

ofile= os.path.join( os.path.dirname(fnamein) ,
"DirBeamParams.pickle")
pickle.dump( res, open( ofile, "w"))


def IntegrationRanges(fnamein):
"Return time ranges suitable for selecting individual integrations"

il=numpy.unique(pyfits.open(fnamein)[1].data.field("date"))
eps=1.0/24/3600/2

res =[ (i-eps, i+eps) for i in il]
return res

def SnapshotRangeSW(fnamein):

"Return time ranges suitable for analysing fast-switched observations"

"""
Just look for gaps caused by the calibrator obs
"""

srccol=pyfits.open(fnamein)[1].data.field("source")
date=pyfits.open(fnamein)[1].data.field("date")

date_target= numpy.unique(date[srccol==2.0])

ddiff = date_target[1:] - date_target[:-1]

# look for gaps longer than 1.5 secs
maxdiff = 1.5 / 24/ 3600

# Don't use last one
gapi = numpy.nonzero((ddiff > maxdiff))[0]

res=[]
eps=1.0/24/3600/2.0
for i in range(len( gapi)-1):
tb= date_target[ gapi[i] +1 ]
te= date_target[ gapi[i+1] ]

res.append( (tb-eps , te+eps))

return res


def IntBeams(fnamein,
keepbeams=False,
fsw=False):

"List of dirty map beam parameters for each integration"

"""
fsw : this is a fast switched observation, reduce accordingly
"""

res=[]
beampars=[]

# Thic keeps hold of the obit input data structures so we are not
# re-opening them all the time
od = obittools.ObitInputData(fnamein,
nowarn=True)

if fsw :
tr = SnapshotRangeSW(od.fnamein)
else:
tr = IntegrationRanges(od.fnamein)

for i, (tb, te) in enumerate(tr):
print tb, te

if fsw:
sources=["F1"]
else:
sources=["SimField"]

obittools.DirtyImage( od,
"t_obit.fits",
trange= [float(tb), float(te)],
sources=sources)

tempbeamname = os.path.join(os.path.dirname(fnamein), "t_obit.fits")

if keepbeams:
shutil.copyfile( tempbeamname,
os.path.join(os.path.dirname(fnamein), "beam-%04i.fits" % i))

fin= pyfits.open(tempbeamname)
res.append(fin[0].data.max())

beampars.append(obittools.FitGaussian( tempbeamname))

return res , beampars


def DirIntBeamsCalc(dirin):
"Find peak flux in each itegration of each file in the supplied directory"

res={}
for fnamein in DirUVSets(dirin):
print fnamein
pf = IntBeams( fnamein)
res[os.path.basename(fnamein)] = pf
return res

ofile= os.path.join( os.path.dirname(fnamein) , "DirIntBeams.pickle")
pickle.dump( res, open( ofile, "w"))

def DirIntBeams(dirin):
"""Find peak fluxes and save to pickle"""

res=DirIntBeamsCalc(dirin)
ofile= os.path.join( os.path.dirname(fnamein) , "DirIntBeams.pickle")
pickle.dump( res, open( ofile, "w"))

def ImagingMemoSnapshots():

"""Dirty maps for illustration of the imaging memo"""

fin="../casasim/midsw/midswitchv3-9-50-12w.ms.fits"

od = obittools.ObitInputData(fin,
nowarn=True)

sources=["F1"]

il= IntegrationRanges(od.fnamein)

il = il[3::100]

for i, (tb, te) in enumerate(il):

obittools.DirtyImage( od,
"beam-midsw-9-50-12w-snap%03i.fits" % (i),
trange= [float(tb), float(te)],
sources=sources)