def arraystat_2 (table, sid, season=0, rob=True, per=True, flags=0) :
""" Calculates a complicated number of parameters for a given star.
Inputs:
table -- an ATpy table with time-series photometry
sid -- a WFCAM source ID.
Optional inputs:
season -- which season to select (1,2,3, or other=All)
rob -- also use Robust statistics? (takes longer, default True)
per -- run period-finding? (takes longer, default True)
flags -- Maximum ppErrBit quality flags to use (default 0)
Returns:
ret -- a data structure containing the computed values.
"""
s_table = data_cut( table, [sid], season=season, flags=flags )
if len(s_table) < 1:
print "no data for %d!" % sid
return None
jcol = s_table.JAPERMAG3; jerr = s_table.JAPERMAG3ERR
hcol = s_table.HAPERMAG3; herr = s_table.HAPERMAG3ERR
kcol = s_table.KAPERMAG3; kerr = s_table.KAPERMAG3ERR
jmhcol=s_table.JMHPNT ; jmherr = s_table.JMHPNTERR
hmkcol=s_table.HMKPNT ; hmkerr = s_table.HMKPNTERR
racol= s_table.RA
decol= s_table.DEC
date = s_table.MEANMJDOBS
messy_table = data_cut( table, [sid], season=-1 )
jppcol=messy_table.JPPERRBITS
hppcol=messy_table.HPPERRBITS
kppcol=messy_table.KPPERRBITS
# make an empty data structure and just assign it information, then return
# the object itself!!! then there's no more worrying about indices.
class Empty():
pass
ret = Empty()
ret.N = len(s_table)
ret.RA = racol.mean()
ret.DEC = decol.mean()
ret.chip = get_chip(date[0], np.degrees(racol[0]), np.degrees(decol[0]))
if ret.N > 4:
ret.one_chip = ( get_chip(date[0], racol[0], decol[0]) ==
get_chip(date[1], racol[1], decol[1]) ==
get_chip(date[2], racol[2], decol[2]) ==
get_chip(date[3], racol[3], decol[3]) )
else:
ret.one_chip = True
ret.Stetson = stetson.S(jcol, jerr, hcol, herr, kcol, kerr)
ret.j = Empty(); ret.j.data = jcol; ret.j.err = jerr
ret.h = Empty(); ret.h.data = hcol; ret.h.err = herr
ret.k = Empty(); ret.k.data = kcol; ret.k.err = kerr
ret.jmh = Empty(); ret.jmh.data=jmhcol; ret.jmh.err = jmherr
ret.hmk = Empty(); ret.hmk.data=hmkcol; ret.hmk.err = hmkerr
bands = [ ret.j, ret.h, ret.k, ret.jmh, ret.hmk ]
for b in bands:
# use b.data, b.err
b.rchi2 = reduced_chisq( b.data, b.err )
b.mean = b.data.mean()
b.rms = b.data.std()
b.min = b.data.min()
b.max = b.data.max()
b.peak_trough = b.max - b.min
b.mean_err = b.err.mean()
# Robust quantifiers simply have an "r" at the end of their names
if rob:
b.datar = rb.removeoutliers(b.data, 3, niter=2)
b.meanr = rb.meanr(b.data)
b.rmsr = rb.stdr(b.data)
b.minr = b.datar.min()
b.maxr = b.datar.max()
b.peak_troughr = b.maxr - b.minr
# Period finding... is a little dodgy still, and might take forever
if per:
b.lsp = lsp(date, b.data, 6., 6.) # apologies if this is cluttered
Jmax = lsp_mask(b.lsp[0], b.lsp[1])
b.lsp_per = 1./ b.lsp[0][Jmax]
b.lsp_pow = b.lsp[1][Jmax]
b.fx2_per = 1./ test_analyze( date, b.data, b.err )
# Finally we'll want to do the whole slope, distance on the JMH graph
# (until I get the fitting done, we'll have to use hmk and jmh naively)
ret.color_slope = (ret.jmh.peak_trough / ret.hmk.peak_trough)
# and the pp_max, using the messy table
ret.jpp_max = jppcol.max()
ret.hpp_max = hppcol.max()
ret.kpp_max = kppcol.max()
return ret
def remove_nights2 (table, analysis):
'''
Removes nights from a table based on the output
of analyze_nights2.
Must be called after analyze_nights2.
Parameters
----------
table : atpy.Table
a data table of time-series photometry from the WFCAM
Science Archive (WSA). Must include all magnitudes, colors,
color errors, ppErrBits, and MeanMjdObs information.
analysis : tuple
The output of analyze_nights2.
Returns
-------
newtable : atpy.Table
The same data table, with all data from bad nights
removed.
badnights : ndarray
The list of timestamps that were rejected.
cuts : list of tuples
The parameters used for rejecting nights.
Order of each tuple:
(mean_hmk, mean_jmh, spread_hmk, spread_jmh)
'''
# First, let's relabel analyze_nights2' output.
nights, hmk, jmh = analysis #this depends on what analyze_nights outputs
master_cloudy = []
cuts = []
for night_set, mean_hmk, mean_jmh in zip(nights, hmk, jmh):
# Let's call in the big guns... robust statistics and outlier clipping
# or, you know, some way to return the outliers.
# Get the robust standard deviation and then write down everyone above.
middle_hmk = rb.meanr(mean_hmk)
middle_jmh = rb.meanr(mean_jmh)
spread_hmk = rb.stdr(mean_hmk)
spread_jmh = rb.stdr(mean_jmh)
ellipse = np.sqrt( ((mean_hmk - middle_hmk)/spread_hmk)**2 +
((mean_jmh - middle_jmh)/spread_jmh)**2 )
cloudy = night_set[ ellipse > 3 ]
print "let's test this."
print "middle: ", middle_hmk
print "spread: ", spread_hmk
print "n_outliers: ", cloudy.size
# now let's save cloudy
master_cloudy.extend(cloudy)
cuts.append((middle_hmk, middle_jmh,
spread_hmk, spread_jmh))
# now let's remove the nights
clean_data = table.where(
np.array([night not in master_cloudy for night in table.MEANMJDOBS])
)
return clean_data, master_cloudy, cuts
def statcruncher (table, sid, season=0, rob=True, per=True,
graded=False, colorslope=False, flags=0) :
"""
Calculates several statistical properties for a given star.
Will work with "lonely" datapoints (i.e. not all JHK mags are
well-defined). Optionally works with graded data, too!
Parameters
----------
table : atpy.Table
Table with time-series photometry
sid : int
13-digit WFCAM source ID of star to plot
season : int, optional
Which observing season of our dataset (1, 2, 3, or all).
Any value that is not the integers (1, 2, or 3) will be
treated as "no season", and no time-cut will be made.
Note that this is the default behavior.
rob : bool, optional
Use robust statistics, in addition to normal ones?
(takes longer, default True)
per : bool, optional
Run period-finding? Uses fast chi-squared and lomb-scargle.
(takes longer, default True)
graded : bool, optional
Also calculate Stetson indices using quality grades as weights?
Uses stetson_graded; requires that the data has been graded by
night_cleanser.null_cleanser_grader().
colorslope : bool, optional
Calculate color slopes? Runs them over (JvJ-H, KvH-K, J-HvH-K).
Make sure your data has been color-error-corrected! Default False.
flags : int, optional
Maximum ppErrBit quality flags to use (default 0)
Returns
-------
ret : data structure
Contains the computed values.
They can be accessed as attributes
(e.g., "ret.j_mean" or "ret.Stetson").
"""
s_table = data_cut ( table, sid, season=season)
if len(s_table) < 1:
print "no data for %d!" % sid
return None
# First, let's compute single-band statistics. This will require
# separate data_cuts on each band.
full_jtable = band_cut(s_table, 'j')
full_htable = band_cut(s_table, 'h')
full_ktable = band_cut(s_table, 'k')
j_table = band_cut(s_table, 'j', max_flag=flags)
h_table = band_cut(s_table, 'h', max_flag=flags)
k_table = band_cut(s_table, 'k', max_flag=flags)
jmh_table = band_cut(j_table, 'h', max_flag=flags)
hmk_table = band_cut(h_table, 'k', max_flag=flags)
# jhk_table used only for colorslope
jhk_table = band_cut( jmh_table, 'k', max_flag=flags)
# get a date (x-axis) for each
jdate = j_table.MEANMJDOBS
hdate = h_table.MEANMJDOBS
kdate = k_table.MEANMJDOBS
jmhdate = jmh_table.MEANMJDOBS
hmkdate = hmk_table.MEANMJDOBS
# date = s_table.MEANMJDOBS
# get a magnitude and magnitude error for each band
jcol = j_table.JAPERMAG3; jerr = j_table.JAPERMAG3ERR
hcol = h_table.HAPERMAG3; herr = h_table.HAPERMAG3ERR
kcol = k_table.KAPERMAG3; kerr = k_table.KAPERMAG3ERR
jmhcol= jmh_table.JMHPNT; jmherr = jmh_table.JMHPNTERR
hmkcol= hmk_table.HMKPNT; hmkerr = hmk_table.HMKPNTERR
# get the RA and DEC columns, checking for sensible values
racol= s_table.RA[(s_table.RA > 0) & (s_table.RA < 7)]
decol= s_table.DEC[(s_table.DEC > -4) & (s_table.DEC < 4)]
# Now let's get some ability to track errorful data.
# messy_table_j = band_cut( s_table, 'j')
# messy_table_h = band_cut( s_table, 'h')
# messy_table_k = band_cut( s_table, 'k')
# jppcol = messy_table_j.JPPERRBITS
# hppcol = messy_table_h.HPPERRBITS
# kppcol = messy_table_k.KPPERRBITS
# make an empty data structure and just assign it information, then return
# the object itself! then there's no more worrying about indices.
class Empty():
pass
ret = Empty()
# How many nights have observations in each band?
ret.N_j = len(j_table)
ret.N_h = len(h_table)
ret.N_k = len(k_table)
# What's the distribution of flags and nights?
js = full_jtable.JPPERRBITS
hs = full_htable.HPPERRBITS
ks = full_ktable.KPPERRBITS
ret.N_j_noflag = len(js[js == 0])
ret.N_h_noflag = len(hs[hs == 0])
ret.N_k_noflag = len(ks[ks == 0])
ret.N_j_info = len(js[(js < 256) & (js > 0)])
ret.N_h_info = len(hs[(hs < 256) & (hs > 0)])
ret.N_k_info = len(ks[(ks < 256) & (ks > 0)])
ret.N_j_warn = len(js[ js >= 256 ])
ret.N_h_warn = len(hs[ hs >= 256 ])
ret.N_k_warn = len(ks[ ks >= 256 ])
# Mean position of this source
ret.RA = racol.mean()
ret.DEC = decol.mean()
# Calculate the Stetson index...
S, choice, stetson_nights = Stetson_machine (s_table, flags)
ret.Stetson = S
ret.Stetson_choice = choice
ret.Stetson_N = stetson_nights
if graded:
# Calculate the graded Stetson index...
g_S, g_choice, g_stetson_nights = (
graded_Stetson_machine (s_table, flags) )
ret.graded_Stetson = g_S
ret.graded_Stetson_choice = g_choice
ret.graded_Stetson_N = g_stetson_nights
# Calculate PSTAR parameters
ret.pstar_mean = s_table.PSTAR.mean()
ret.pstar_median = np.median(s_table.PSTAR)
ret.pstar_rms = s_table.PSTAR.std()
# Create parallel data structures for each band, so we can iterate
ret.j = Empty(); ret.j.data = jcol; ret.j.err = jerr; ret.j.date = jdate
ret.h = Empty(); ret.h.data = hcol; ret.h.err = herr; ret.h.date = hdate
ret.k = Empty(); ret.k.data = kcol; ret.k.err = kerr; ret.k.date = kdate
ret.jmh = Empty(); ret.jmh.data=jmhcol; ret.jmh.err = jmherr
ret.hmk = Empty(); ret.hmk.data=hmkcol; ret.hmk.err = hmkerr
ret.jmh.date = jmhdate; ret.hmk.date = hmkdate
ret.j.N = ret.N_j ; ret.h.N = ret.N_h ; ret.k.N = ret.N_k
ret.jmh.N = len(jmh_table) ; ret.hmk.N = len(hmk_table)
bands = [ ret.j, ret.h, ret.k, ret.jmh, ret.hmk ]
for b in bands:
# use b.data, b.err
# if this band is empty, don't try to do the following assignments
if b.N == 0: continue
b.rchi2 = reduced_chisq( b.data, b.err )
b.mean = b.data.mean()
b.median = np.median(b.data) # dao
b.rms = b.data.std()
b.min = b.data.min()
b.max = b.data.max()
b.range = b.max - b.min
b.err_mean = b.err.mean() #dao
b.err_median = np.median(b.err) #dao
b.err_rms = b.err.std() #dao
b.err_min = b.err.min() #dao
b.err_max = b.err.max() #dao
b.err_range = b.err_max - b.err_min #dao
# Robust quantifiers simply have an "r" at the end of their names
if rob:
b.datar, b.indr = rb.removeoutliers(b.data, 3, niter=2, retind=True)
b.errr = b.err[b.indr]
b.meanr = rb.meanr(b.data)
b.medianr = rb.medianr(b.data) # dao
b.rmsr = rb.stdr(b.data)
b.minr = b.datar.min()
b.maxr = b.datar.max()
b.ranger = b.maxr - b.minr
b.err_meanr = b.errr.mean() # dao
b.err_medianr = np.median(b.errr) #dao
b.err_rmsr = b.errr.std() #dao
b.err_minr = b.errr.min() #dao
b.err_maxr = b.errr.max() #dao
b.err_ranger = b.err_maxr - b.err_minr #dao
# Period finding... is a little dodgy still, and might take forever
if per==True and b.N > 2:
hifac = lsp_tuning(b.date)
b.lsp = lsp(b.date, b.data, 6., hifac)
Jmax = lsp_mask(b.lsp[0], b.lsp[1])
b.lsp_per = 1./ b.lsp[0][Jmax]
b.lsp_pow = b.lsp[1][Jmax]
b.lsp_sig = getSignificance(b.lsp[0], b.lsp[1], b.lsp[2], 6.)[Jmax]
best_freq, chimin = test_analyze( b.date, b.data, b.err,
ret_chimin=True )
b.fx2_per, b.fx2_chimin = 1./best_freq, chimin
if colorslope:
# J vs J-H : use jmh_table exclusively
(ret.jjh_slope, a, ret.jjh_slope_err) = (
slope( jmh_table.JMHPNT, jmh_table.JAPERMAG3,
jmh_table.JMHPNTERR, jmh_table.JAPERMAG3ERR,
verbose=False) )
# K vs H-K : use hmk_table exclusively
(ret.khk_slope, a, ret.khk_slope_err) = (
slope( hmk_table.HMKPNT, hmk_table.KAPERMAG3,
hmk_table.HMKPNTERR, hmk_table.KAPERMAG3ERR,
verbose=False) )
# J-H vs H-K : use jhk_table exclusively
(ret.jhk_slope, a, ret.jhk_slope_err) = (
slope( jhk_table.HMKPNT, jhk_table.JMHPNT,
jhk_table.HMKPNTERR, jhk_table.JMHPNTERR,
verbose=False) )
# and the pp_max, using the messy table
# (slated for a re-implementation)
# ret.jpp_max = jppcol.max()
# ret.hpp_max = hppcol.max()
# ret.kpp_max = kppcol.max()
return ret
