source: trunk/python/scantable.py@ 1550

Last change on this file since 1550 was 1545, checked in by Malte Marquarding, 16 years ago

allow for (max,min) mask windows

  • Property svn:eol-style set to native
  • Property svn:keywords set to Author Date Id Revision
File size: 70.1 KB
Line 
1from asap._asap import Scantable
2from asap import rcParams
3from asap import print_log
4from asap import asaplog
5from asap import selector
6from asap import linecatalog
7from asap import _n_bools, mask_not, mask_and, mask_or
8
9class scantable(Scantable):
10 """
11 The ASAP container for scans
12 """
13
14 def __init__(self, filename, average=None, unit=None):
15 """
16 Create a scantable from a saved one or make a reference
17 Parameters:
18 filename: the name of an asap table on disk
19 or
20 the name of a rpfits/sdfits/ms file
21 (integrations within scans are auto averaged
22 and the whole file is read)
23 or
24 [advanced] a reference to an existing
25 scantable
26 average: average all integrations withinb a scan on read.
27 The default (True) is taken from .asaprc.
28 unit: brightness unit; must be consistent with K or Jy.
29 Over-rides the default selected by the reader
30 (input rpfits/sdfits/ms) or replaces the value
31 in existing scantables
32 """
33 if average is None:
34 average = rcParams['scantable.autoaverage']
35 varlist = vars()
36 from asap._asap import stmath
37 self._math = stmath()
38 if isinstance(filename, Scantable):
39 Scantable.__init__(self, filename)
40 else:
41 if isinstance(filename, str):# or \
42# (isinstance(filename, list) or isinstance(filename, tuple)) \
43# and isinstance(filename[-1], str):
44 import os.path
45 filename = os.path.expandvars(filename)
46 filename = os.path.expanduser(filename)
47 if not os.path.exists(filename):
48 s = "File '%s' not found." % (filename)
49 if rcParams['verbose']:
50 asaplog.push(s)
51 print asaplog.pop().strip()
52 return
53 raise IOError(s)
54 if os.path.isdir(filename) \
55 and not os.path.exists(filename+'/table.f1'):
56 # crude check if asap table
57 if os.path.exists(filename+'/table.info'):
58 ondisk = rcParams['scantable.storage'] == 'disk'
59 Scantable.__init__(self, filename, ondisk)
60 if unit is not None:
61 self.set_fluxunit(unit)
62 self.set_freqframe(rcParams['scantable.freqframe'])
63 else:
64 msg = "The given file '%s'is not a valid " \
65 "asap table." % (filename)
66 if rcParams['verbose']:
67 print msg
68 return
69 else:
70 raise IOError(msg)
71 else:
72 self._fill([filename], unit, average)
73 elif (isinstance(filename, list) or isinstance(filename, tuple)) \
74 and isinstance(filename[-1], str):
75 self._fill(filename, unit, average)
76 self._add_history("scantable", varlist)
77 print_log()
78
79 def save(self, name=None, format=None, overwrite=False):
80 """
81 Store the scantable on disk. This can be an asap (aips++) Table,
82 SDFITS or MS2 format.
83 Parameters:
84 name: the name of the outputfile. For format "ASCII"
85 this is the root file name (data in 'name'.txt
86 and header in 'name'_header.txt)
87 format: an optional file format. Default is ASAP.
88 Allowed are - 'ASAP' (save as ASAP [aips++] Table),
89 'SDFITS' (save as SDFITS file)
90 'ASCII' (saves as ascii text file)
91 'MS2' (saves as an aips++
92 MeasurementSet V2)
93 'FITS' (save as image FITS - not
94 readable by class)
95 'CLASS' (save as FITS readable by CLASS)
96 overwrite: If the file should be overwritten if it exists.
97 The default False is to return with warning
98 without writing the output. USE WITH CARE.
99 Example:
100 scan.save('myscan.asap')
101 scan.save('myscan.sdfits', 'SDFITS')
102 """
103 from os import path
104 if format is None: format = rcParams['scantable.save']
105 suffix = '.'+format.lower()
106 if name is None or name == "":
107 name = 'scantable'+suffix
108 msg = "No filename given. Using default name %s..." % name
109 asaplog.push(msg)
110 name = path.expandvars(name)
111 if path.isfile(name) or path.isdir(name):
112 if not overwrite:
113 msg = "File %s exists." % name
114 if rcParams['verbose']:
115 print msg
116 return
117 else:
118 raise IOError(msg)
119 format2 = format.upper()
120 if format2 == 'ASAP':
121 self._save(name)
122 else:
123 from asap._asap import stwriter as stw
124 writer = stw(format2)
125 writer.write(self, name)
126 print_log()
127 return
128
129 def copy(self):
130 """
131 Return a copy of this scantable.
132 Note:
133 This makes a full (deep) copy. scan2 = scan1 makes a reference.
134 Parameters:
135 none
136 Example:
137 copiedscan = scan.copy()
138 """
139 sd = scantable(Scantable._copy(self))
140 return sd
141
142 def drop_scan(self, scanid=None):
143 """
144 Return a new scantable where the specified scan number(s) has(have)
145 been dropped.
146 Parameters:
147 scanid: a (list of) scan number(s)
148 """
149 from asap import _is_sequence_or_number as _is_valid
150 from asap import _to_list
151 from asap import unique
152 if not _is_valid(scanid):
153 if rcParams['verbose']:
154 print "Please specify a scanno to drop from the scantable"
155 return
156 else:
157 raise RuntimeError("No scan given")
158 try:
159 scanid = _to_list(scanid)
160 allscans = unique([ self.getscan(i) for i in range(self.nrow())])
161 for sid in scanid: allscans.remove(sid)
162 if len(allscans) == 0:
163 raise ValueError("Can't remove all scans")
164 except ValueError:
165 if rcParams['verbose']:
166 print "Couldn't find any match."
167 return
168 else: raise
169 try:
170 bsel = self.get_selection()
171 sel = selector()
172 sel.set_scans(allscans)
173 self.set_selection(bsel+sel)
174 scopy = self._copy()
175 self.set_selection(bsel)
176 return scantable(scopy)
177 except RuntimeError:
178 if rcParams['verbose']:
179 print "Couldn't find any match."
180 else:
181 raise
182
183
184 def get_scan(self, scanid=None):
185 """
186 Return a specific scan (by scanno) or collection of scans (by
187 source name) in a new scantable.
188 Note:
189 See scantable.drop_scan() for the inverse operation.
190 Parameters:
191 scanid: a (list of) scanno or a source name, unix-style
192 patterns are accepted for source name matching, e.g.
193 '*_R' gets all 'ref scans
194 Example:
195 # get all scans containing the source '323p459'
196 newscan = scan.get_scan('323p459')
197 # get all 'off' scans
198 refscans = scan.get_scan('*_R')
199 # get a susbset of scans by scanno (as listed in scan.summary())
200 newscan = scan.get_scan([0, 2, 7, 10])
201 """
202 if scanid is None:
203 if rcParams['verbose']:
204 print "Please specify a scan no or name to " \
205 "retrieve from the scantable"
206 return
207 else:
208 raise RuntimeError("No scan given")
209
210 try:
211 bsel = self.get_selection()
212 sel = selector()
213 if type(scanid) is str:
214 sel.set_name(scanid)
215 self.set_selection(bsel+sel)
216 scopy = self._copy()
217 self.set_selection(bsel)
218 return scantable(scopy)
219 elif type(scanid) is int:
220 sel.set_scans([scanid])
221 self.set_selection(bsel+sel)
222 scopy = self._copy()
223 self.set_selection(bsel)
224 return scantable(scopy)
225 elif type(scanid) is list:
226 sel.set_scans(scanid)
227 self.set_selection(sel)
228 scopy = self._copy()
229 self.set_selection(bsel)
230 return scantable(scopy)
231 else:
232 msg = "Illegal scanid type, use 'int' or 'list' if ints."
233 if rcParams['verbose']:
234 print msg
235 else:
236 raise TypeError(msg)
237 except RuntimeError:
238 if rcParams['verbose']: print "Couldn't find any match."
239 else: raise
240
241 def __str__(self):
242 return Scantable._summary(self, True)
243
244 def summary(self, filename=None):
245 """
246 Print a summary of the contents of this scantable.
247 Parameters:
248 filename: the name of a file to write the putput to
249 Default - no file output
250 verbose: print extra info such as the frequency table
251 The default (False) is taken from .asaprc
252 """
253 info = Scantable._summary(self, True)
254 #if verbose is None: verbose = rcParams['scantable.verbosesummary']
255 if filename is not None:
256 if filename is "":
257 filename = 'scantable_summary.txt'
258 from os.path import expandvars, isdir
259 filename = expandvars(filename)
260 if not isdir(filename):
261 data = open(filename, 'w')
262 data.write(info)
263 data.close()
264 else:
265 msg = "Illegal file name '%s'." % (filename)
266 if rcParams['verbose']:
267 print msg
268 else:
269 raise IOError(msg)
270 if rcParams['verbose']:
271 try:
272 from IPython.genutils import page as pager
273 except ImportError:
274 from pydoc import pager
275 pager(info)
276 else:
277 return info
278
279 def get_spectrum(self, rowno):
280 """Return the spectrum for the current row in the scantable as a list.
281 Parameters:
282 rowno: the row number to retrieve the spectrum from
283 """
284 return self._getspectrum(rowno)
285
286 def get_mask(self, rowno):
287 """Return the mask for the current row in the scantable as a list.
288 Parameters:
289 rowno: the row number to retrieve the mask from
290 """
291 return self._getmask(rowno)
292
293 def set_spectrum(self, spec, rowno):
294 """Return the spectrum for the current row in the scantable as a list.
295 Parameters:
296 spec: the spectrum
297 rowno: the row number to set the spectrum for
298 """
299 assert(len(spec) == self.nchan())
300 return self._setspectrum(spec, rowno)
301
302 def get_selection(self):
303 """
304 Get the selection object currently set on this scantable.
305 Parameters:
306 none
307 Example:
308 sel = scan.get_selection()
309 sel.set_ifs(0) # select IF 0
310 scan.set_selection(sel) # apply modified selection
311 """
312 return selector(self._getselection())
313
314 def set_selection(self, selection=selector()):
315 """
316 Select a subset of the data. All following operations on this scantable
317 are only applied to thi selection.
318 Parameters:
319 selection: a selector object (default unset the selection)
320 Examples:
321 sel = selector() # create a selection object
322 self.set_scans([0, 3]) # select SCANNO 0 and 3
323 scan.set_selection(sel) # set the selection
324 scan.summary() # will only print summary of scanno 0 an 3
325 scan.set_selection() # unset the selection
326 """
327 self._setselection(selection)
328
329 def stats(self, stat='stddev', mask=None):
330 """
331 Determine the specified statistic of the current beam/if/pol
332 Takes a 'mask' as an optional parameter to specify which
333 channels should be excluded.
334 Parameters:
335 stat: 'min', 'max', 'sumsq', 'sum', 'mean'
336 'var', 'stddev', 'avdev', 'rms', 'median'
337 mask: an optional mask specifying where the statistic
338 should be determined.
339 Example:
340 scan.set_unit('channel')
341 msk = scan.create_mask([100, 200], [500, 600])
342 scan.stats(stat='mean', mask=m)
343 """
344 if mask == None:
345 mask = []
346 axes = ['Beam', 'IF', 'Pol', 'Time']
347 if not self._check_ifs():
348 raise ValueError("Cannot apply mask as the IFs have different "
349 "number of channels. Please use setselection() "
350 "to select individual IFs")
351
352 statvals = self._math._stats(self, mask, stat)
353 out = ''
354 axes = []
355 for i in range(self.nrow()):
356 axis = []
357 axis.append(self.getscan(i))
358 axis.append(self.getbeam(i))
359 axis.append(self.getif(i))
360 axis.append(self.getpol(i))
361 axis.append(self.getcycle(i))
362 axes.append(axis)
363 tm = self._gettime(i)
364 src = self._getsourcename(i)
365 out += 'Scan[%d] (%s) ' % (axis[0], src)
366 out += 'Time[%s]:\n' % (tm)
367 if self.nbeam(-1) > 1: out += ' Beam[%d] ' % (axis[1])
368 if self.nif(-1) > 1: out += ' IF[%d] ' % (axis[2])
369 if self.npol(-1) > 1: out += ' Pol[%d] ' % (axis[3])
370 out += '= %3.3f\n' % (statvals[i])
371 out += "--------------------------------------------------\n"
372
373 if rcParams['verbose']:
374 print "--------------------------------------------------"
375 print " ", stat
376 print "--------------------------------------------------"
377 print out
378 #else:
379 #retval = { 'axesnames': ['scanno', 'beamno', 'ifno', 'polno', 'cycleno'],
380 # 'axes' : axes,
381 # 'data': statvals}
382 return statvals
383
384 def stddev(self, mask=None):
385 """
386 Determine the standard deviation of the current beam/if/pol
387 Takes a 'mask' as an optional parameter to specify which
388 channels should be excluded.
389 Parameters:
390 mask: an optional mask specifying where the standard
391 deviation should be determined.
392
393 Example:
394 scan.set_unit('channel')
395 msk = scan.create_mask([100, 200], [500, 600])
396 scan.stddev(mask=m)
397 """
398 return self.stats(stat='stddev', mask=mask);
399
400
401 def get_column_names(self):
402 """
403 Return a list of column names, which can be used for selection.
404 """
405 return list(Scantable.get_column_names(self))
406
407 def get_tsys(self):
408 """
409 Return the System temperatures.
410 Returns:
411 a list of Tsys values for the current selection
412 """
413
414 return self._row_callback(self._gettsys, "Tsys")
415
416 def _row_callback(self, callback, label):
417 axes = []
418 axesnames = ['scanno', 'beamno', 'ifno', 'polno', 'cycleno']
419 out = ""
420 outvec = []
421 for i in range(self.nrow()):
422 axis = []
423 axis.append(self.getscan(i))
424 axis.append(self.getbeam(i))
425 axis.append(self.getif(i))
426 axis.append(self.getpol(i))
427 axis.append(self.getcycle(i))
428 axes.append(axis)
429 tm = self._gettime(i)
430 src = self._getsourcename(i)
431 out += 'Scan[%d] (%s) ' % (axis[0], src)
432 out += 'Time[%s]:\n' % (tm)
433 if self.nbeam(-1) > 1: out += ' Beam[%d] ' % (axis[1])
434 if self.nif(-1) > 1: out += ' IF[%d] ' % (axis[2])
435 if self.npol(-1) > 1: out += ' Pol[%d] ' % (axis[3])
436 outvec.append(callback(i))
437 out += '= %3.3f\n' % (outvec[i])
438 out += "--------------------------------------------------\n"
439 if rcParams['verbose']:
440 print "--------------------------------------------------"
441 print " %s" % (label)
442 print "--------------------------------------------------"
443 print out
444 # disabled because the vector seems more useful
445 #retval = {'axesnames': axesnames, 'axes': axes, 'data': outvec}
446 return outvec
447
448 def _get_column(self, callback, row=-1):
449 """
450 """
451 if row == -1:
452 return [callback(i) for i in range(self.nrow())]
453 else:
454 if 0 <= row < self.nrow():
455 return callback(row)
456
457
458 def get_time(self, row=-1, asdatetime=False):
459 """
460 Get a list of time stamps for the observations.
461 Return a datetime object for each integration time stamp in the scantable.
462 Parameters:
463 row: row no of integration. Default -1 return all rows
464 asdatetime: return values as datetime objects rather than strings
465 Example:
466 none
467 """
468 from time import strptime
469 from datetime import datetime
470 times = self._get_column(self._gettime, row)
471 if not asdatetime:
472 return times
473 format = "%Y/%m/%d/%H:%M:%S"
474 if isinstance(times, list):
475 return [datetime(*strptime(i, format)[:6]) for i in times]
476 else:
477 return datetime(*strptime(times, format)[:6])
478
479
480 def get_inttime(self, row=-1):
481 """
482 Get a list of integration times for the observations.
483 Return a time in seconds for each integration in the scantable.
484 Parameters:
485 row: row no of integration. Default -1 return all rows.
486 Example:
487 none
488 """
489 return self._get_column(self._getinttime, row)
490
491
492 def get_sourcename(self, row=-1):
493 """
494 Get a list source names for the observations.
495 Return a string for each integration in the scantable.
496 Parameters:
497 row: row no of integration. Default -1 return all rows.
498 Example:
499 none
500 """
501 return self._get_column(self._getsourcename, row)
502
503 def get_elevation(self, row=-1):
504 """
505 Get a list of elevations for the observations.
506 Return a float for each integration in the scantable.
507 Parameters:
508 row: row no of integration. Default -1 return all rows.
509 Example:
510 none
511 """
512 return self._get_column(self._getelevation, row)
513
514 def get_azimuth(self, row=-1):
515 """
516 Get a list of azimuths for the observations.
517 Return a float for each integration in the scantable.
518 Parameters:
519 row: row no of integration. Default -1 return all rows.
520 Example:
521 none
522 """
523 return self._get_column(self._getazimuth, row)
524
525 def get_parangle(self, row=-1):
526 """
527 Get a list of parallactic angles for the observations.
528 Return a float for each integration in the scantable.
529 Parameters:
530 row: row no of integration. Default -1 return all rows.
531 Example:
532 none
533 """
534 return self._get_column(self._getparangle, row)
535
536 def get_direction(self, row=-1):
537 """
538 Get a list of Positions on the sky (direction) for the observations.
539 Return a float for each integration in the scantable.
540 Parameters:
541 row: row no of integration. Default -1 return all rows
542 Example:
543 none
544 """
545 return self._get_column(self._getdirection, row)
546
547 def get_directionval(self, row=-1):
548 """
549 Get a list of Positions on the sky (direction) for the observations.
550 Return a float for each integration in the scantable.
551 Parameters:
552 row: row no of integration. Default -1 return all rows
553 Example:
554 none
555 """
556 return self._get_column(self._getdirectionvec, row)
557
558
559 def set_unit(self, unit='channel'):
560 """
561 Set the unit for all following operations on this scantable
562 Parameters:
563 unit: optional unit, default is 'channel'
564 one of '*Hz', 'km/s', 'channel', ''
565 """
566 varlist = vars()
567 if unit in ['', 'pixel', 'channel']:
568 unit = ''
569 inf = list(self._getcoordinfo())
570 inf[0] = unit
571 self._setcoordinfo(inf)
572 self._add_history("set_unit", varlist)
573
574 def set_instrument(self, instr):
575 """
576 Set the instrument for subsequent processing.
577 Parameters:
578 instr: Select from 'ATPKSMB', 'ATPKSHOH', 'ATMOPRA',
579 'DSS-43' (Tid), 'CEDUNA', and 'HOBART'
580 """
581 self._setInstrument(instr)
582 self._add_history("set_instument", vars())
583 print_log()
584
585 def set_feedtype(self, feedtype):
586 """
587 Overwrite the feed type, which might not be set correctly.
588 Parameters:
589 feedtype: 'linear' or 'circular'
590 """
591 self._setfeedtype(feedtype)
592 self._add_history("set_feedtype", vars())
593 print_log()
594
595 def set_doppler(self, doppler='RADIO'):
596 """
597 Set the doppler for all following operations on this scantable.
598 Parameters:
599 doppler: One of 'RADIO', 'OPTICAL', 'Z', 'BETA', 'GAMMA'
600 """
601 varlist = vars()
602 inf = list(self._getcoordinfo())
603 inf[2] = doppler
604 self._setcoordinfo(inf)
605 self._add_history("set_doppler", vars())
606 print_log()
607
608 def set_freqframe(self, frame=None):
609 """
610 Set the frame type of the Spectral Axis.
611 Parameters:
612 frame: an optional frame type, default 'LSRK'. Valid frames are:
613 'REST', 'TOPO', 'LSRD', 'LSRK', 'BARY',
614 'GEO', 'GALACTO', 'LGROUP', 'CMB'
615 Examples:
616 scan.set_freqframe('BARY')
617 """
618 if frame is None: frame = rcParams['scantable.freqframe']
619 varlist = vars()
620 valid = ['REST', 'TOPO', 'LSRD', 'LSRK', 'BARY', \
621 'GEO', 'GALACTO', 'LGROUP', 'CMB']
622
623 if frame in valid:
624 inf = list(self._getcoordinfo())
625 inf[1] = frame
626 self._setcoordinfo(inf)
627 self._add_history("set_freqframe", varlist)
628 else:
629 msg = "Please specify a valid freq type. Valid types are:\n", valid
630 if rcParams['verbose']:
631 print msg
632 else:
633 raise TypeError(msg)
634 print_log()
635
636 def set_dirframe(self, frame=""):
637 """
638 Set the frame type of the Direction on the sky.
639 Parameters:
640 frame: an optional frame type, default ''. Valid frames are:
641 'J2000', 'B1950', 'GALACTIC'
642 Examples:
643 scan.set_dirframe('GALACTIC')
644 """
645 varlist = vars()
646 try:
647 Scantable.set_dirframe(self, frame)
648 except RuntimeError, msg:
649 if rcParams['verbose']:
650 print msg
651 else:
652 raise
653 self._add_history("set_dirframe", varlist)
654
655 def get_unit(self):
656 """
657 Get the default unit set in this scantable
658 Returns:
659 A unit string
660 """
661 inf = self._getcoordinfo()
662 unit = inf[0]
663 if unit == '': unit = 'channel'
664 return unit
665
666 def get_abcissa(self, rowno=0):
667 """
668 Get the abcissa in the current coordinate setup for the currently
669 selected Beam/IF/Pol
670 Parameters:
671 rowno: an optional row number in the scantable. Default is the
672 first row, i.e. rowno=0
673 Returns:
674 The abcissa values and the format string (as a dictionary)
675 """
676 abc = self._getabcissa(rowno)
677 lbl = self._getabcissalabel(rowno)
678 print_log()
679 return abc, lbl
680
681 def flag(self, mask=None):
682 """
683 Flag the selected data using an optional channel mask.
684 Parameters:
685 mask: an optional channel mask, created with create_mask. Default
686 (no mask) is all channels.
687 """
688 varlist = vars()
689 if mask is None:
690 mask = []
691 try:
692 self._flag(mask)
693 except RuntimeError, msg:
694 if rcParams['verbose']:
695 print msg
696 return
697 else: raise
698 self._add_history("flag", varlist)
699
700 def lag_flag(self, frequency, width=0.0, unit="GHz", insitu=None):
701 """
702 Flag the data in 'lag' space by providing a frequency to remove.
703 Flagged data in the scantable gets set to 0.0 before the fft.
704 No taper is applied.
705 Parameters:
706 frequency: the frequency (really a period within the bandwidth)
707 to remove
708 width: the width of the frequency to remove, to remove a
709 range of frequencies around the centre.
710 unit: the frequency unit (default "GHz")
711 Notes:
712 It is recommended to flag edges of the band or strong
713 signals beforehand.
714 """
715 if insitu is None: insitu = rcParams['insitu']
716 self._math._setinsitu(insitu)
717 varlist = vars()
718 base = { "GHz": 1000000000., "MHz": 1000000., "kHz": 1000., "Hz": 1. }
719 if not base.has_key(unit):
720 raise ValueError("%s is not a valid unit." % unit)
721 try:
722 s = scantable(self._math._lag_flag(self, frequency*base[unit],
723 width*base[unit]))
724 except RuntimeError, msg:
725 if rcParams['verbose']:
726 print msg
727 return
728 else: raise
729 s._add_history("lag_flag", varlist)
730 print_log()
731 if insitu:
732 self._assign(s)
733 else:
734 return s
735
736
737 def create_mask(self, *args, **kwargs):
738 """
739 Compute and return a mask based on [min, max] windows.
740 The specified windows are to be INCLUDED, when the mask is
741 applied.
742 Parameters:
743 [min, max], [min2, max2], ...
744 Pairs of start/end points (inclusive)specifying the regions
745 to be masked
746 invert: optional argument. If specified as True,
747 return an inverted mask, i.e. the regions
748 specified are EXCLUDED
749 row: create the mask using the specified row for
750 unit conversions, default is row=0
751 only necessary if frequency varies over rows.
752 Example:
753 scan.set_unit('channel')
754 a)
755 msk = scan.create_mask([400, 500], [800, 900])
756 # masks everything outside 400 and 500
757 # and 800 and 900 in the unit 'channel'
758
759 b)
760 msk = scan.create_mask([400, 500], [800, 900], invert=True)
761 # masks the regions between 400 and 500
762 # and 800 and 900 in the unit 'channel'
763 c)
764 mask only channel 400
765 msk = scan.create_mask([400, 400])
766 """
767 row = 0
768 if kwargs.has_key("row"):
769 row = kwargs.get("row")
770 data = self._getabcissa(row)
771 u = self._getcoordinfo()[0]
772 if rcParams['verbose']:
773 if u == "": u = "channel"
774 msg = "The current mask window unit is %s" % u
775 i = self._check_ifs()
776 if not i:
777 msg += "\nThis mask is only valid for IF=%d" % (self.getif(i))
778 asaplog.push(msg)
779 n = self.nchan()
780 msk = _n_bools(n, False)
781 # test if args is a 'list' or a 'normal *args - UGLY!!!
782
783 ws = (isinstance(args[-1][-1], int) or isinstance(args[-1][-1], float)) \
784 and args or args[0]
785 for window in ws:
786 if len(window) != 2:
787 raise ValueError("A window needs to be defined as [start, end]")
788 if window[0] > window[1]:
789 tmp = window[0]
790 window[0] = window[1]
791 window[1] = tmp
792 for i in range(n):
793 if data[i] >= window[0] and data[i] <= window[1]:
794 msk[i] = True
795 if kwargs.has_key('invert'):
796 if kwargs.get('invert'):
797 msk = mask_not(msk)
798 print_log()
799 return msk
800
801 def get_restfreqs(self):
802 """
803 Get the restfrequency(s) stored in this scantable.
804 The return value(s) are always of unit 'Hz'
805 Parameters:
806 none
807 Returns:
808 a list of doubles
809 """
810 return list(self._getrestfreqs())
811
812
813 def set_restfreqs(self, freqs=None, unit='Hz'):
814 """
815 Set or replace the restfrequency specified and
816 If the 'freqs' argument holds a scalar,
817 then that rest frequency will be applied to all the selected
818 data. If the 'freqs' argument holds
819 a vector, then it MUST be of equal or smaller length than
820 the number of IFs (and the available restfrequencies will be
821 replaced by this vector). In this case, *all* data have
822 the restfrequency set per IF according
823 to the corresponding value you give in the 'freqs' vector.
824 E.g. 'freqs=[1e9, 2e9]' would mean IF 0 gets restfreq 1e9 and
825 IF 1 gets restfreq 2e9.
826 You can also specify the frequencies via a linecatalog.
827
828 Parameters:
829 freqs: list of rest frequency values or string idenitfiers
830 unit: unit for rest frequency (default 'Hz')
831
832 Example:
833 # set the given restfrequency for the whole table
834 scan.set_restfreqs(freqs=1.4e9)
835 # If thee number of IFs in the data is >= 2 IF0 gets the first
836 # value IF1 the second...
837 scan.set_restfreqs(freqs=[1.4e9, 1.67e9])
838 #set the given restfrequency for the whole table (by name)
839 scan.set_restfreqs(freqs="OH1667")
840
841 Note:
842 To do more sophisticate Restfrequency setting, e.g. on a
843 source and IF basis, use scantable.set_selection() before using
844 this function.
845 # provide your scantable is call scan
846 selection = selector()
847 selection.set_name("ORION*")
848 selection.set_ifs([1])
849 scan.set_selection(selection)
850 scan.set_restfreqs(freqs=86.6e9)
851
852 """
853 varlist = vars()
854 from asap import linecatalog
855 # simple value
856 if isinstance(freqs, int) or isinstance(freqs, float):
857 self._setrestfreqs(freqs, "",unit)
858 # list of values
859 elif isinstance(freqs, list) or isinstance(freqs, tuple):
860 # list values are scalars
861 if isinstance(freqs[-1], int) or isinstance(freqs[-1], float):
862 sel = selector()
863 savesel = self._getselection()
864 iflist = self.getifnos()
865 for i in xrange(len(freqs)):
866 sel.set_ifs(iflist[i])
867 self._setselection(sel)
868 self._setrestfreqs(freqs[i], "",unit)
869 self._setselection(savesel)
870 # list values are tuples, (value, name)
871 elif isinstance(freqs[-1], dict):
872 sel = selector()
873 savesel = self._getselection()
874 iflist = self.getifnos()
875 for i in xrange(len(freqs)):
876 sel.set_ifs(iflist[i])
877 self._setselection(sel)
878 self._setrestfreqs(freqs[i]["value"],
879 freqs[i]["name"], "MHz")
880 self._setselection(savesel)
881 # freqs are to be taken from a linecatalog
882 elif isinstance(freqs, linecatalog):
883 sel = selector()
884 savesel = self._getselection()
885 iflist = self.getifnos()
886 for i in xrange(freqs.nrow()):
887 sel.set_ifs(iflist[i])
888 self._setselection(sel)
889 self._setrestfreqs(freqs.get_frequency(i),
890 freqs.get_name(i), "MHz")
891 # ensure that we are not iterating past nIF
892 if i == self.nif()-1: break
893 self._setselection(savesel)
894 else:
895 return
896 self._add_history("set_restfreqs", varlist)
897
898 def shift_refpix(self, delta):
899 """
900 Shift the reference pixel of the Spectra Coordinate by an
901 integer amount.
902 Parameters:
903 delta: the amount to shift by
904 Note:
905 Be careful using this with broadband data.
906 """
907 Scantable.shift(self, delta)
908
909 def history(self, filename=None):
910 """
911 Print the history. Optionally to a file.
912 Parameters:
913 filename: The name of the file to save the history to.
914 """
915 hist = list(self._gethistory())
916 out = "-"*80
917 for h in hist:
918 if h.startswith("---"):
919 out += "\n"+h
920 else:
921 items = h.split("##")
922 date = items[0]
923 func = items[1]
924 items = items[2:]
925 out += "\n"+date+"\n"
926 out += "Function: %s\n Parameters:" % (func)
927 for i in items:
928 s = i.split("=")
929 out += "\n %s = %s" % (s[0], s[1])
930 out += "\n"+"-"*80
931 if filename is not None:
932 if filename is "":
933 filename = 'scantable_history.txt'
934 import os
935 filename = os.path.expandvars(os.path.expanduser(filename))
936 if not os.path.isdir(filename):
937 data = open(filename, 'w')
938 data.write(out)
939 data.close()
940 else:
941 msg = "Illegal file name '%s'." % (filename)
942 if rcParams['verbose']:
943 print msg
944 else:
945 raise IOError(msg)
946 if rcParams['verbose']:
947 try:
948 from IPython.genutils import page as pager
949 except ImportError:
950 from pydoc import pager
951 pager(out)
952 else:
953 return out
954 return
955 #
956 # Maths business
957 #
958
959 def average_time(self, mask=None, scanav=False, weight='tint', align=False):
960 """
961 Return the (time) weighted average of a scan.
962 Note:
963 in channels only - align if necessary
964 Parameters:
965 mask: an optional mask (only used for 'var' and 'tsys'
966 weighting)
967 scanav: True averages each scan separately
968 False (default) averages all scans together,
969 weight: Weighting scheme.
970 'none' (mean no weight)
971 'var' (1/var(spec) weighted)
972 'tsys' (1/Tsys**2 weighted)
973 'tint' (integration time weighted)
974 'tintsys' (Tint/Tsys**2)
975 'median' ( median averaging)
976 The default is 'tint'
977 align: align the spectra in velocity before averaging. It takes
978 the time of the first spectrum as reference time.
979 Example:
980 # time average the scantable without using a mask
981 newscan = scan.average_time()
982 """
983 varlist = vars()
984 if weight is None: weight = 'TINT'
985 if mask is None: mask = ()
986 if scanav: scanav = "SCAN"
987 else: scanav = "NONE"
988 scan = (self, )
989 try:
990 if align:
991 scan = (self.freq_align(insitu=False), )
992 s = None
993 if weight.upper() == 'MEDIAN':
994 s = scantable(self._math._averagechannel(scan[0], 'MEDIAN',
995 scanav))
996 else:
997 s = scantable(self._math._average(scan, mask, weight.upper(),
998 scanav))
999 except RuntimeError, msg:
1000 if rcParams['verbose']:
1001 print msg
1002 return
1003 else: raise
1004 s._add_history("average_time", varlist)
1005 print_log()
1006 return s
1007
1008 def convert_flux(self, jyperk=None, eta=None, d=None, insitu=None):
1009 """
1010 Return a scan where all spectra are converted to either
1011 Jansky or Kelvin depending upon the flux units of the scan table.
1012 By default the function tries to look the values up internally.
1013 If it can't find them (or if you want to over-ride), you must
1014 specify EITHER jyperk OR eta (and D which it will try to look up
1015 also if you don't set it). jyperk takes precedence if you set both.
1016 Parameters:
1017 jyperk: the Jy / K conversion factor
1018 eta: the aperture efficiency
1019 d: the geomtric diameter (metres)
1020 insitu: if False a new scantable is returned.
1021 Otherwise, the scaling is done in-situ
1022 The default is taken from .asaprc (False)
1023 """
1024 if insitu is None: insitu = rcParams['insitu']
1025 self._math._setinsitu(insitu)
1026 varlist = vars()
1027 if jyperk is None: jyperk = -1.0
1028 if d is None: d = -1.0
1029 if eta is None: eta = -1.0
1030 s = scantable(self._math._convertflux(self, d, eta, jyperk))
1031 s._add_history("convert_flux", varlist)
1032 print_log()
1033 if insitu: self._assign(s)
1034 else: return s
1035
1036 def gain_el(self, poly=None, filename="", method="linear", insitu=None):
1037 """
1038 Return a scan after applying a gain-elevation correction.
1039 The correction can be made via either a polynomial or a
1040 table-based interpolation (and extrapolation if necessary).
1041 You specify polynomial coefficients, an ascii table or neither.
1042 If you specify neither, then a polynomial correction will be made
1043 with built in coefficients known for certain telescopes (an error
1044 will occur if the instrument is not known).
1045 The data and Tsys are *divided* by the scaling factors.
1046 Parameters:
1047 poly: Polynomial coefficients (default None) to compute a
1048 gain-elevation correction as a function of
1049 elevation (in degrees).
1050 filename: The name of an ascii file holding correction factors.
1051 The first row of the ascii file must give the column
1052 names and these MUST include columns
1053 "ELEVATION" (degrees) and "FACTOR" (multiply data
1054 by this) somewhere.
1055 The second row must give the data type of the
1056 column. Use 'R' for Real and 'I' for Integer.
1057 An example file would be
1058 (actual factors are arbitrary) :
1059
1060 TIME ELEVATION FACTOR
1061 R R R
1062 0.1 0 0.8
1063 0.2 20 0.85
1064 0.3 40 0.9
1065 0.4 60 0.85
1066 0.5 80 0.8
1067 0.6 90 0.75
1068 method: Interpolation method when correcting from a table.
1069 Values are "nearest", "linear" (default), "cubic"
1070 and "spline"
1071 insitu: if False a new scantable is returned.
1072 Otherwise, the scaling is done in-situ
1073 The default is taken from .asaprc (False)
1074 """
1075
1076 if insitu is None: insitu = rcParams['insitu']
1077 self._math._setinsitu(insitu)
1078 varlist = vars()
1079 if poly is None:
1080 poly = ()
1081 from os.path import expandvars
1082 filename = expandvars(filename)
1083 s = scantable(self._math._gainel(self, poly, filename, method))
1084 s._add_history("gain_el", varlist)
1085 print_log()
1086 if insitu: self._assign(s)
1087 else: return s
1088
1089 def freq_align(self, reftime=None, method='cubic', insitu=None):
1090 """
1091 Return a scan where all rows have been aligned in frequency/velocity.
1092 The alignment frequency frame (e.g. LSRK) is that set by function
1093 set_freqframe.
1094 Parameters:
1095 reftime: reference time to align at. By default, the time of
1096 the first row of data is used.
1097 method: Interpolation method for regridding the spectra.
1098 Choose from "nearest", "linear", "cubic" (default)
1099 and "spline"
1100 insitu: if False a new scantable is returned.
1101 Otherwise, the scaling is done in-situ
1102 The default is taken from .asaprc (False)
1103 """
1104 if insitu is None: insitu = rcParams["insitu"]
1105 self._math._setinsitu(insitu)
1106 varlist = vars()
1107 if reftime is None: reftime = ""
1108 s = scantable(self._math._freq_align(self, reftime, method))
1109 s._add_history("freq_align", varlist)
1110 print_log()
1111 if insitu: self._assign(s)
1112 else: return s
1113
1114 def opacity(self, tau, insitu=None):
1115 """
1116 Apply an opacity correction. The data
1117 and Tsys are multiplied by the correction factor.
1118 Parameters:
1119 tau: Opacity from which the correction factor is
1120 exp(tau*ZD)
1121 where ZD is the zenith-distance
1122 insitu: if False a new scantable is returned.
1123 Otherwise, the scaling is done in-situ
1124 The default is taken from .asaprc (False)
1125 """
1126 if insitu is None: insitu = rcParams['insitu']
1127 self._math._setinsitu(insitu)
1128 varlist = vars()
1129 s = scantable(self._math._opacity(self, tau))
1130 s._add_history("opacity", varlist)
1131 print_log()
1132 if insitu: self._assign(s)
1133 else: return s
1134
1135 def bin(self, width=5, insitu=None):
1136 """
1137 Return a scan where all spectra have been binned up.
1138 Parameters:
1139 width: The bin width (default=5) in pixels
1140 insitu: if False a new scantable is returned.
1141 Otherwise, the scaling is done in-situ
1142 The default is taken from .asaprc (False)
1143 """
1144 if insitu is None: insitu = rcParams['insitu']
1145 self._math._setinsitu(insitu)
1146 varlist = vars()
1147 s = scantable(self._math._bin(self, width))
1148 s._add_history("bin", varlist)
1149 print_log()
1150 if insitu: self._assign(s)
1151 else: return s
1152
1153
1154 def resample(self, width=5, method='cubic', insitu=None):
1155 """
1156 Return a scan where all spectra have been binned up.
1157
1158 Parameters:
1159 width: The bin width (default=5) in pixels
1160 method: Interpolation method when correcting from a table.
1161 Values are "nearest", "linear", "cubic" (default)
1162 and "spline"
1163 insitu: if False a new scantable is returned.
1164 Otherwise, the scaling is done in-situ
1165 The default is taken from .asaprc (False)
1166 """
1167 if insitu is None: insitu = rcParams['insitu']
1168 self._math._setinsitu(insitu)
1169 varlist = vars()
1170 s = scantable(self._math._resample(self, method, width))
1171 s._add_history("resample", varlist)
1172 print_log()
1173 if insitu: self._assign(s)
1174 else: return s
1175
1176
1177 def average_pol(self, mask=None, weight='none'):
1178 """
1179 Average the Polarisations together.
1180 Parameters:
1181 mask: An optional mask defining the region, where the
1182 averaging will be applied. The output will have all
1183 specified points masked.
1184 weight: Weighting scheme. 'none' (default), 'var' (1/var(spec)
1185 weighted), or 'tsys' (1/Tsys**2 weighted)
1186 """
1187 varlist = vars()
1188 if mask is None:
1189 mask = ()
1190 s = scantable(self._math._averagepol(self, mask, weight.upper()))
1191 s._add_history("average_pol", varlist)
1192 print_log()
1193 return s
1194
1195 def average_beam(self, mask=None, weight='none'):
1196 """
1197 Average the Beams together.
1198 Parameters:
1199 mask: An optional mask defining the region, where the
1200 averaging will be applied. The output will have all
1201 specified points masked.
1202 weight: Weighting scheme. 'none' (default), 'var' (1/var(spec)
1203 weighted), or 'tsys' (1/Tsys**2 weighted)
1204 """
1205 varlist = vars()
1206 if mask is None:
1207 mask = ()
1208 s = scantable(self._math._averagebeams(self, mask, weight.upper()))
1209 s._add_history("average_beam", varlist)
1210 print_log()
1211 return s
1212
1213 def convert_pol(self, poltype=None):
1214 """
1215 Convert the data to a different polarisation type.
1216 Parameters:
1217 poltype: The new polarisation type. Valid types are:
1218 "linear", "stokes" and "circular"
1219 """
1220 varlist = vars()
1221 try:
1222 s = scantable(self._math._convertpol(self, poltype))
1223 except RuntimeError, msg:
1224 if rcParams['verbose']:
1225 print msg
1226 return
1227 else:
1228 raise
1229 s._add_history("convert_pol", varlist)
1230 print_log()
1231 return s
1232
1233 def smooth(self, kernel="hanning", width=5.0, insitu=None):
1234 """
1235 Smooth the spectrum by the specified kernel (conserving flux).
1236 Parameters:
1237 kernel: The type of smoothing kernel. Select from
1238 'hanning' (default), 'gaussian', 'boxcar' and
1239 'rmedian'
1240 width: The width of the kernel in pixels. For hanning this is
1241 ignored otherwise it defauls to 5 pixels.
1242 For 'gaussian' it is the Full Width Half
1243 Maximum. For 'boxcar' it is the full width.
1244 For 'rmedian' it is the half width.
1245 insitu: if False a new scantable is returned.
1246 Otherwise, the scaling is done in-situ
1247 The default is taken from .asaprc (False)
1248 Example:
1249 none
1250 """
1251 if insitu is None: insitu = rcParams['insitu']
1252 self._math._setinsitu(insitu)
1253 varlist = vars()
1254 s = scantable(self._math._smooth(self, kernel.lower(), width))
1255 s._add_history("smooth", varlist)
1256 print_log()
1257 if insitu: self._assign(s)
1258 else: return s
1259
1260
1261 def poly_baseline(self, mask=None, order=0, plot=False, uselin=False, insitu=None):
1262 """
1263 Return a scan which has been baselined (all rows) by a polynomial.
1264 Parameters:
1265 mask: an optional mask
1266 order: the order of the polynomial (default is 0)
1267 plot: plot the fit and the residual. In this each
1268 indivual fit has to be approved, by typing 'y'
1269 or 'n'
1270 uselin: use linear polynomial fit
1271 insitu: if False a new scantable is returned.
1272 Otherwise, the scaling is done in-situ
1273 The default is taken from .asaprc (False)
1274 Example:
1275 # return a scan baselined by a third order polynomial,
1276 # not using a mask
1277 bscan = scan.poly_baseline(order=3)
1278 """
1279 if insitu is None: insitu = rcParams['insitu']
1280 varlist = vars()
1281 if mask is None:
1282 mask = [True for i in xrange(self.nchan(-1))]
1283 from asap.asapfitter import fitter
1284 try:
1285 f = fitter()
1286 f.set_scan(self, mask)
1287 #f.set_function(poly=order)
1288 if uselin:
1289 f.set_function(lpoly=order)
1290 else:
1291 f.set_function(poly=order)
1292 s = f.auto_fit(insitu, plot=plot)
1293 s._add_history("poly_baseline", varlist)
1294 print_log()
1295 if insitu: self._assign(s)
1296 else: return s
1297 except RuntimeError:
1298 msg = "The fit failed, possibly because it didn't converge."
1299 if rcParams['verbose']:
1300 print msg
1301 return
1302 else:
1303 raise RuntimeError(msg)
1304
1305
1306 def auto_poly_baseline(self, mask=[], edge=(0, 0), order=0,
1307 threshold=3, chan_avg_limit=1, plot=False,
1308 insitu=None):
1309 """
1310 Return a scan which has been baselined (all rows) by a polynomial.
1311 Spectral lines are detected first using linefinder and masked out
1312 to avoid them affecting the baseline solution.
1313
1314 Parameters:
1315 mask: an optional mask retreived from scantable
1316 edge: an optional number of channel to drop at
1317 the edge of spectrum. If only one value is
1318 specified, the same number will be dropped from
1319 both sides of the spectrum. Default is to keep
1320 all channels. Nested tuples represent individual
1321 edge selection for different IFs (a number of spectral
1322 channels can be different)
1323 order: the order of the polynomial (default is 0)
1324 threshold: the threshold used by line finder. It is better to
1325 keep it large as only strong lines affect the
1326 baseline solution.
1327 chan_avg_limit:
1328 a maximum number of consequtive spectral channels to
1329 average during the search of weak and broad lines.
1330 The default is no averaging (and no search for weak
1331 lines). If such lines can affect the fitted baseline
1332 (e.g. a high order polynomial is fitted), increase this
1333 parameter (usually values up to 8 are reasonable). Most
1334 users of this method should find the default value
1335 sufficient.
1336 plot: plot the fit and the residual. In this each
1337 indivual fit has to be approved, by typing 'y'
1338 or 'n'
1339 insitu: if False a new scantable is returned.
1340 Otherwise, the scaling is done in-situ
1341 The default is taken from .asaprc (False)
1342
1343 Example:
1344 scan2=scan.auto_poly_baseline(order=7)
1345 """
1346 if insitu is None: insitu = rcParams['insitu']
1347 varlist = vars()
1348 from asap.asapfitter import fitter
1349 from asap.asaplinefind import linefinder
1350 from asap import _is_sequence_or_number as _is_valid
1351
1352 # check whether edge is set up for each IF individually
1353 individualedge = False;
1354 if len(edge) > 1:
1355 if isinstance(edge[0], list) or isinstance(edge[0], tuple):
1356 individualedge = True;
1357
1358 if not _is_valid(edge, int) and not individualedge:
1359 raise ValueError, "Parameter 'edge' has to be an integer or a \
1360 pair of integers specified as a tuple. Nested tuples are allowed \
1361 to make individual selection for different IFs."
1362
1363 curedge = (0, 0)
1364 if individualedge:
1365 for edgepar in edge:
1366 if not _is_valid(edgepar, int):
1367 raise ValueError, "Each element of the 'edge' tuple has \
1368 to be a pair of integers or an integer."
1369 else:
1370 curedge = edge;
1371
1372 # setup fitter
1373 f = fitter()
1374 f.set_function(poly=order)
1375
1376 # setup line finder
1377 fl = linefinder()
1378 fl.set_options(threshold=threshold,avg_limit=chan_avg_limit)
1379
1380 if not insitu:
1381 workscan = self.copy()
1382 else:
1383 workscan = self
1384
1385 fl.set_scan(workscan)
1386
1387 rows = range(workscan.nrow())
1388 asaplog.push("Processing:")
1389 for r in rows:
1390 msg = " Scan[%d] Beam[%d] IF[%d] Pol[%d] Cycle[%d]" % \
1391 (workscan.getscan(r), workscan.getbeam(r), workscan.getif(r), \
1392 workscan.getpol(r), workscan.getcycle(r))
1393 asaplog.push(msg, False)
1394
1395 # figure out edge parameter
1396 if individualedge:
1397 if len(edge) >= workscan.getif(r):
1398 raise RuntimeError, "Number of edge elements appear to " \
1399 "be less than the number of IFs"
1400 curedge = edge[workscan.getif(r)]
1401
1402 # setup line finder
1403 fl.find_lines(r, mask, curedge)
1404 f.set_data(workscan._getabcissa(r), workscan._getspectrum(r),
1405 mask_and(workscan._getmask(r), fl.get_mask()))
1406 f.fit()
1407 x = f.get_parameters()
1408 if plot:
1409 f.plot(residual=True)
1410 x = raw_input("Accept fit ( [y]/n ): ")
1411 if x.upper() == 'N':
1412 continue
1413 workscan._setspectrum(f.fitter.getresidual(), r)
1414 if plot:
1415 f._p.unmap()
1416 f._p = None
1417 workscan._add_history("auto_poly_baseline", varlist)
1418 if insitu:
1419 self._assign(workscan)
1420 else:
1421 return workscan
1422
1423 def rotate_linpolphase(self, angle):
1424 """
1425 Rotate the phase of the complex polarization O=Q+iU correlation.
1426 This is always done in situ in the raw data. So if you call this
1427 function more than once then each call rotates the phase further.
1428 Parameters:
1429 angle: The angle (degrees) to rotate (add) by.
1430 Examples:
1431 scan.rotate_linpolphase(2.3)
1432 """
1433 varlist = vars()
1434 self._math._rotate_linpolphase(self, angle)
1435 self._add_history("rotate_linpolphase", varlist)
1436 print_log()
1437 return
1438
1439
1440 def rotate_xyphase(self, angle):
1441 """
1442 Rotate the phase of the XY correlation. This is always done in situ
1443 in the data. So if you call this function more than once
1444 then each call rotates the phase further.
1445 Parameters:
1446 angle: The angle (degrees) to rotate (add) by.
1447 Examples:
1448 scan.rotate_xyphase(2.3)
1449 """
1450 varlist = vars()
1451 self._math._rotate_xyphase(self, angle)
1452 self._add_history("rotate_xyphase", varlist)
1453 print_log()
1454 return
1455
1456 def swap_linears(self):
1457 """
1458 Swap the linear polarisations XX and YY, or better the first two
1459 polarisations as this also works for ciculars.
1460 """
1461 varlist = vars()
1462 self._math._swap_linears(self)
1463 self._add_history("swap_linears", varlist)
1464 print_log()
1465 return
1466
1467 def invert_phase(self):
1468 """
1469 Invert the phase of the complex polarisation
1470 """
1471 varlist = vars()
1472 self._math._invert_phase(self)
1473 self._add_history("invert_phase", varlist)
1474 print_log()
1475 return
1476
1477 def add(self, offset, insitu=None):
1478 """
1479 Return a scan where all spectra have the offset added
1480 Parameters:
1481 offset: the offset
1482 insitu: if False a new scantable is returned.
1483 Otherwise, the scaling is done in-situ
1484 The default is taken from .asaprc (False)
1485 """
1486 if insitu is None: insitu = rcParams['insitu']
1487 self._math._setinsitu(insitu)
1488 varlist = vars()
1489 s = scantable(self._math._unaryop(self, offset, "ADD", False))
1490 s._add_history("add", varlist)
1491 print_log()
1492 if insitu:
1493 self._assign(s)
1494 else:
1495 return s
1496
1497 def scale(self, factor, tsys=True, insitu=None):
1498 """
1499 Return a scan where all spectra are scaled by the give 'factor'
1500 Parameters:
1501 factor: the scaling factor
1502 insitu: if False a new scantable is returned.
1503 Otherwise, the scaling is done in-situ
1504 The default is taken from .asaprc (False)
1505 tsys: if True (default) then apply the operation to Tsys
1506 as well as the data
1507 """
1508 if insitu is None: insitu = rcParams['insitu']
1509 self._math._setinsitu(insitu)
1510 varlist = vars()
1511 s = scantable(self._math._unaryop(self, factor, "MUL", tsys))
1512 s._add_history("scale", varlist)
1513 print_log()
1514 if insitu:
1515 self._assign(s)
1516 else:
1517 return s
1518
1519 def set_sourcetype(self, match, matchtype="pattern",
1520 sourcetype="reference"):
1521 """
1522 Set the type of the source to be an source or reference scan
1523 using the provided pattern:
1524 Parameters:
1525 match: a Unix style pattern, regular expression or selector
1526 matchtype: 'pattern' (default) UNIX style pattern or
1527 'regex' regular expression
1528 sourcetype: the type of the source to use (source/reference)
1529 """
1530 varlist = vars()
1531 basesel = self.get_selection()
1532 stype = -1
1533 if sourcetype.lower().startswith("r"):
1534 stype = 1
1535 elif sourcetype.lower().startswith("s"):
1536 stype = 0
1537 else:
1538 raise ValueError("Illegal sourcetype use s(ource) or r(eference)")
1539 if matchtype.lower().startswith("p"):
1540 matchtype = "pattern"
1541 elif matchtype.lower().startswith("r"):
1542 matchtype = "regex"
1543 else:
1544 raise ValueError("Illegal matchtype, use p(attern) or r(egex)")
1545 sel = selector()
1546 if isinstance(match, selector):
1547 sel = match
1548 else:
1549 sel.set_query("SRCNAME == %s('%s')" % (matchtype, match))
1550 self.set_selection(basesel+sel)
1551 self._setsourcetype(stype)
1552 self.set_selection(basesel)
1553 s._add_history("set_sourcetype", varlist)
1554
1555 def auto_quotient(self, preserve=True, mode='paired'):
1556 """
1557 This function allows to build quotients automatically.
1558 It assumes the observation to have the same numer of
1559 "ons" and "offs"
1560 Parameters:
1561 preserve: you can preserve (default) the continuum or
1562 remove it. The equations used are
1563 preserve: Output = Toff * (on/off) - Toff
1564 remove: Output = Toff * (on/off) - Ton
1565 mode: the on/off detection mode
1566 'paired' (default)
1567 identifies 'off' scans by the
1568 trailing '_R' (Mopra/Parkes) or
1569 '_e'/'_w' (Tid) and matches
1570 on/off pairs from the observing pattern
1571 'time'
1572 finds the closest off in time
1573
1574 """
1575 modes = ["time", "paired"]
1576 if not mode in modes:
1577 msg = "please provide valid mode. Valid modes are %s" % (modes)
1578 raise ValueError(msg)
1579 varlist = vars()
1580 s = None
1581 if mode.lower() == "paired":
1582 basesel = self.get_selection()
1583 sel = selector()+basesel
1584 sel.set_query("SRCTYPE==1")
1585 self.set_selection(sel)
1586 offs = self.copy()
1587 sel.set_query("SRCTYPE==0")
1588 self.set_selection(sel)
1589 ons = self.copy()
1590 s = scantable(self._math._quotient(ons, offs, preserve))
1591 self.set_selection(basesel)
1592 elif mode.lower() == "time":
1593 s = scantable(self._math._auto_quotient(self, mode, preserve))
1594 s._add_history("auto_quotient", varlist)
1595 print_log()
1596 return s
1597
1598 def mx_quotient(self, mask = None, weight='median', preserve=True):
1599 """
1600 Form a quotient using "off" beams when observing in "MX" mode.
1601 Parameters:
1602 mask: an optional mask to be used when weight == 'stddev'
1603 weight: How to average the off beams. Default is 'median'.
1604 preserve: you can preserve (default) the continuum or
1605 remove it. The equations used are
1606 preserve: Output = Toff * (on/off) - Toff
1607 remove: Output = Toff * (on/off) - Ton
1608 """
1609 if mask is None: mask = ()
1610 varlist = vars()
1611 on = scantable(self._math._mx_extract(self, 'on'))
1612 preoff = scantable(self._math._mx_extract(self, 'off'))
1613 off = preoff.average_time(mask=mask, weight=weight, scanav=False)
1614 from asapmath import quotient
1615 q = quotient(on, off, preserve)
1616 q._add_history("mx_quotient", varlist)
1617 print_log()
1618 return q
1619
1620 def freq_switch(self, insitu=None):
1621 """
1622 Apply frequency switching to the data.
1623 Parameters:
1624 insitu: if False a new scantable is returned.
1625 Otherwise, the swictching is done in-situ
1626 The default is taken from .asaprc (False)
1627 Example:
1628 none
1629 """
1630 if insitu is None: insitu = rcParams['insitu']
1631 self._math._setinsitu(insitu)
1632 varlist = vars()
1633 s = scantable(self._math._freqswitch(self))
1634 s._add_history("freq_switch", varlist)
1635 print_log()
1636 if insitu: self._assign(s)
1637 else: return s
1638
1639 def recalc_azel(self):
1640 """
1641 Recalculate the azimuth and elevation for each position.
1642 Parameters:
1643 none
1644 Example:
1645 """
1646 varlist = vars()
1647 self._recalcazel()
1648 self._add_history("recalc_azel", varlist)
1649 print_log()
1650 return
1651
1652 def __add__(self, other):
1653 varlist = vars()
1654 s = None
1655 if isinstance(other, scantable):
1656 s = scantable(self._math._binaryop(self, other, "ADD"))
1657 elif isinstance(other, float):
1658 s = scantable(self._math._unaryop(self, other, "ADD", False))
1659 else:
1660 raise TypeError("Other input is not a scantable or float value")
1661 s._add_history("operator +", varlist)
1662 print_log()
1663 return s
1664
1665 def __sub__(self, other):
1666 """
1667 implicit on all axes and on Tsys
1668 """
1669 varlist = vars()
1670 s = None
1671 if isinstance(other, scantable):
1672 s = scantable(self._math._binaryop(self, other, "SUB"))
1673 elif isinstance(other, float):
1674 s = scantable(self._math._unaryop(self, other, "SUB", False))
1675 else:
1676 raise TypeError("Other input is not a scantable or float value")
1677 s._add_history("operator -", varlist)
1678 print_log()
1679 return s
1680
1681 def __mul__(self, other):
1682 """
1683 implicit on all axes and on Tsys
1684 """
1685 varlist = vars()
1686 s = None
1687 if isinstance(other, scantable):
1688 s = scantable(self._math._binaryop(self, other, "MUL"))
1689 elif isinstance(other, float):
1690 s = scantable(self._math._unaryop(self, other, "MUL", False))
1691 else:
1692 raise TypeError("Other input is not a scantable or float value")
1693 s._add_history("operator *", varlist)
1694 print_log()
1695 return s
1696
1697
1698 def __div__(self, other):
1699 """
1700 implicit on all axes and on Tsys
1701 """
1702 varlist = vars()
1703 s = None
1704 if isinstance(other, scantable):
1705 s = scantable(self._math._binaryop(self, other, "DIV"))
1706 elif isinstance(other, float):
1707 if other == 0.0:
1708 raise ZeroDivisionError("Dividing by zero is not recommended")
1709 s = scantable(self._math._unaryop(self, other, "DIV", False))
1710 else:
1711 raise TypeError("Other input is not a scantable or float value")
1712 s._add_history("operator /", varlist)
1713 print_log()
1714 return s
1715
1716 def get_fit(self, row=0):
1717 """
1718 Print or return the stored fits for a row in the scantable
1719 Parameters:
1720 row: the row which the fit has been applied to.
1721 """
1722 if row > self.nrow():
1723 return
1724 from asap.asapfit import asapfit
1725 fit = asapfit(self._getfit(row))
1726 if rcParams['verbose']:
1727 print fit
1728 return
1729 else:
1730 return fit.as_dict()
1731
1732 def flag_nans(self):
1733 """
1734 Utility function to flag NaN values in the scantable.
1735 """
1736 import numpy
1737 basesel = self.get_selection()
1738 for i in range(self.nrow()):
1739 sel = selector()+basesel
1740 sel.set_scans(self.getscan(i))
1741 sel.set_beams(self.getbeam(i))
1742 sel.set_ifs(self.getif(i))
1743 sel.set_polarisations(self.getpol(i))
1744 self.set_selection(sel)
1745 nans = numpy.isnan(self._getspectrum(0))
1746 if numpy.any(nans):
1747 bnans = [ bool(v) for v in nans]
1748 self.flag(bnans)
1749 self.set_selection(basesel)
1750
1751
1752 def _add_history(self, funcname, parameters):
1753 if not rcParams['scantable.history']:
1754 return
1755 # create date
1756 sep = "##"
1757 from datetime import datetime
1758 dstr = datetime.now().strftime('%Y/%m/%d %H:%M:%S')
1759 hist = dstr+sep
1760 hist += funcname+sep#cdate+sep
1761 if parameters.has_key('self'): del parameters['self']
1762 for k, v in parameters.iteritems():
1763 if type(v) is dict:
1764 for k2, v2 in v.iteritems():
1765 hist += k2
1766 hist += "="
1767 if isinstance(v2, scantable):
1768 hist += 'scantable'
1769 elif k2 == 'mask':
1770 if isinstance(v2, list) or isinstance(v2, tuple):
1771 hist += str(self._zip_mask(v2))
1772 else:
1773 hist += str(v2)
1774 else:
1775 hist += str(v2)
1776 else:
1777 hist += k
1778 hist += "="
1779 if isinstance(v, scantable):
1780 hist += 'scantable'
1781 elif k == 'mask':
1782 if isinstance(v, list) or isinstance(v, tuple):
1783 hist += str(self._zip_mask(v))
1784 else:
1785 hist += str(v)
1786 else:
1787 hist += str(v)
1788 hist += sep
1789 hist = hist[:-2] # remove trailing '##'
1790 self._addhistory(hist)
1791
1792
1793 def _zip_mask(self, mask):
1794 mask = list(mask)
1795 i = 0
1796 segments = []
1797 while mask[i:].count(1):
1798 i += mask[i:].index(1)
1799 if mask[i:].count(0):
1800 j = i + mask[i:].index(0)
1801 else:
1802 j = len(mask)
1803 segments.append([i, j])
1804 i = j
1805 return segments
1806
1807 def _get_ordinate_label(self):
1808 fu = "("+self.get_fluxunit()+")"
1809 import re
1810 lbl = "Intensity"
1811 if re.match(".K.", fu):
1812 lbl = "Brightness Temperature "+ fu
1813 elif re.match(".Jy.", fu):
1814 lbl = "Flux density "+ fu
1815 return lbl
1816
1817 def _check_ifs(self):
1818 nchans = [self.nchan(i) for i in range(self.nif(-1))]
1819 nchans = filter(lambda t: t > 0, nchans)
1820 return (sum(nchans)/len(nchans) == nchans[0])
1821
1822 def _fill(self, names, unit, average):
1823 import os
1824 from asap._asap import stfiller
1825 first = True
1826 fullnames = []
1827 for name in names:
1828 name = os.path.expandvars(name)
1829 name = os.path.expanduser(name)
1830 if not os.path.exists(name):
1831 msg = "File '%s' does not exists" % (name)
1832 if rcParams['verbose']:
1833 asaplog.push(msg)
1834 print asaplog.pop().strip()
1835 return
1836 raise IOError(msg)
1837 fullnames.append(name)
1838 if average:
1839 asaplog.push('Auto averaging integrations')
1840 stype = int(rcParams['scantable.storage'].lower() == 'disk')
1841 for name in fullnames:
1842 tbl = Scantable(stype)
1843 r = stfiller(tbl)
1844 rx = rcParams['scantable.reference']
1845 r._setreferenceexpr(rx)
1846 msg = "Importing %s..." % (name)
1847 asaplog.push(msg, False)
1848 print_log()
1849 r._open(name, -1, -1)
1850 r._read()
1851 if average:
1852 tbl = self._math._average((tbl, ), (), 'NONE', 'SCAN')
1853 if not first:
1854 tbl = self._math._merge([self, tbl])
1855 Scantable.__init__(self, tbl)
1856 r._close()
1857 del r, tbl
1858 first = False
1859 if unit is not None:
1860 self.set_fluxunit(unit)
1861 self.set_freqframe(rcParams['scantable.freqframe'])
1862
1863 def __getitem__(self, key):
1864 if key < 0:
1865 key += self.nrow()
1866 if key >= self.nrow():
1867 raise IndexError("Row index out of range.")
1868 return self._getspectrum(key)
1869
1870 def __setitem__(self, key, value):
1871 if key < 0:
1872 key += self.nrow()
1873 if key >= self.nrow():
1874 raise IndexError("Row index out of range.")
1875 if not hasattr(value, "__len__") or \
1876 len(value) > self.nchan(self.getif(key)):
1877 raise ValueError("Spectrum length doesn't match.")
1878 return self._setspectrum(value, key)
1879
1880 def __len__(self):
1881 return self.nrow()
1882
1883 def __iter__(self):
1884 for i in range(len(self)):
1885 yield self[i]
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