[2647] | 1 | import os, shutil |
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| 2 | import numpy |
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| 3 | import numpy.fft as FFT |
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| 4 | import math |
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| 5 | |
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| 6 | from asap.scantable import scantable |
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| 7 | from asap.parameters import rcParams |
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| 8 | from asap.logging import asaplog, asaplog_post_dec |
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| 9 | from asap.selector import selector |
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| 10 | from asap.asapgrid import asapgrid2 |
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[2707] | 11 | from asap._asap import SBSeparator |
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[2647] | 12 | |
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| 13 | class sbseparator: |
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| 14 | """ |
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[2649] | 15 | The sbseparator class is defined to separate SIGNAL and IMAGE |
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| 16 | sideband spectra observed by frequency-switching technique. |
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| 17 | It also helps supressing emmission of IMAGE sideband. |
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| 18 | *** WARNING *** THIS MODULE IS EXPERIMENTAL |
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| 19 | Known issues: |
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| 20 | - Frequencies of IMAGE sideband cannot be reconstructed from |
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| 21 | information in scantable in sideband sparation. Frequency |
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| 22 | setting of SIGNAL sideband is stored in output table for now. |
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| 23 | - Flag information (stored in FLAGTRA) is ignored. |
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[2647] | 24 | |
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| 25 | Example: |
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| 26 | # Create sideband separator instance whith 3 input data |
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| 27 | sbsep = sbseparator(['test1.asap', 'test2.asap', 'test3.asap']) |
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| 28 | # Set reference IFNO and tolerance to select data |
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| 29 | sbsep.set_frequency(5, 30, frame='TOPO') |
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| 30 | # Set direction tolerance to select data in unit of radian |
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| 31 | sbsep.set_dirtol(1.e-5) |
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| 32 | # Set rejection limit of solution |
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| 33 | sbsep.set_limit(0.2) |
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| 34 | # Solve image sideband as well |
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| 35 | sbsep.set_both(True) |
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| 36 | # Invoke sideband separation |
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| 37 | sbsep.separate('testout.asap', overwrite = True) |
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| 38 | """ |
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| 39 | def __init__(self, infiles): |
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[2772] | 40 | self._separator = SBSeparator(infiles) |
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[2647] | 41 | |
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| 42 | |
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| 43 | def set_frequency(self, baseif, freqtol, frame=""): |
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| 44 | """ |
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| 45 | Set IFNO and frequency tolerance to select data to process. |
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| 46 | |
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| 47 | Parameters: |
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| 48 | - reference IFNO to process in the first table in the list |
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[2794] | 49 | - frequency tolerance from reference IF to select data (string) |
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[2647] | 50 | frame : frequency frame to select IF |
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| 51 | """ |
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[2794] | 52 | if type(freqtol) in (float, int): |
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| 53 | freqtol = str(freqtol) |
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| 54 | elif isinstance(freqtol, dict): |
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| 55 | try: |
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| 56 | freqtol = str(freqtol['value']) + freqtol['unit'] |
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| 57 | except: |
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| 58 | raise ValueError, "Invalid frequency tolerance." |
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| 59 | self._separator.set_freq(baseif, freqtol, frame) |
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[2647] | 60 | |
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| 61 | |
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[2794] | 62 | def set_dirtol(self, dirtol=["2arcsec", "2arcsec"]): |
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[2647] | 63 | """ |
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| 64 | Set tolerance of direction to select data |
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| 65 | """ |
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[2794] | 66 | if isinstance(dirtol, str): |
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| 67 | dirtol = [dirtol] |
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[2647] | 68 | |
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[2794] | 69 | self._separator.set_dirtol(dirtol) |
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| 70 | |
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| 71 | |
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| 72 | def set_shift(self, imageshift=[]): |
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[2647] | 73 | """ |
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| 74 | Set shift mode and channel shift of image band. |
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| 75 | |
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[2794] | 76 | imageshift : a list of number of channels shifted in image |
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| 77 | side band of each scantable. |
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| 78 | If the shifts are not set, they are assumed to be |
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| 79 | equal to those of signal side band, but in opposite |
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| 80 | direction as usual by LO1 offsetting of DSB receivers. |
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[2647] | 81 | """ |
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[2794] | 82 | if not imageshift: |
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| 83 | imageshift = [] |
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| 84 | self._separator.set_shift(imageshift) |
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[2647] | 85 | |
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[2794] | 86 | |
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[2647] | 87 | @asaplog_post_dec |
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| 88 | def set_both(self, flag=False): |
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| 89 | """ |
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| 90 | Resolve both image and signal sideband when True. |
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| 91 | """ |
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[2794] | 92 | self._separator.solve_both(flag) |
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| 93 | if flag: |
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| 94 | asaplog.push("Both signal and image sidebands will be solved and stored in separate tables.") |
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[2647] | 95 | else: |
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[2794] | 96 | asaplog.push("Only signal sideband will be solved and stored in an table.") |
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[2647] | 97 | |
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| 98 | @asaplog_post_dec |
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| 99 | def set_limit(self, threshold=0.2): |
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| 100 | """ |
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| 101 | Set rejection limit of solution. |
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| 102 | """ |
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[2794] | 103 | self._separator.set_limit(threshold) |
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[2647] | 104 | |
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| 105 | |
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| 106 | @asaplog_post_dec |
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| 107 | def set_solve_other(self, flag=False): |
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| 108 | """ |
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| 109 | Calculate spectra by subtracting the solution of the other sideband |
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| 110 | when True. |
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| 111 | """ |
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[2794] | 112 | self._separator.subtract_other(flag) |
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[2647] | 113 | if flag: |
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| 114 | asaplog.push("Expert mode: solution are obtained by subtraction of the other sideband.") |
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| 115 | |
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[2794] | 116 | |
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[2807] | 117 | def set_lo1(self, lo1, frame="TOPO", reftime=-1, refdir=""): |
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[2707] | 118 | """ |
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| 119 | Set LO1 frequency to calculate frequency of image sideband. |
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[2647] | 120 | |
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[2794] | 121 | lo1 : LO1 frequency |
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| 122 | frame : the frequency frame of LO1 |
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| 123 | reftime : the reference time used in frequency frame conversion. |
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| 124 | refdir : the reference direction used in frequency frame conversion. |
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[2707] | 125 | """ |
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[2807] | 126 | self._separator.set_lo1(lo1, frame, reftime, refdir) |
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[2707] | 127 | |
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| 128 | |
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[2711] | 129 | def set_lo1root(self, name): |
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| 130 | """ |
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| 131 | Set MS name which stores LO1 frequency of signal side band. |
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| 132 | It is used to calculate frequency of image sideband. |
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| 133 | |
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| 134 | name : MS name which contains 'ASDM_SPECTRALWINDOW' and |
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| 135 | 'ASDM_RECEIVER' tables. |
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| 136 | """ |
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[2712] | 137 | self._separator.set_lo1root(name) |
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[2711] | 138 | |
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[2647] | 139 | @asaplog_post_dec |
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| 140 | def separate(self, outname="", overwrite=False): |
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| 141 | """ |
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| 142 | Invoke sideband separation. |
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| 143 | |
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| 144 | outname : a name of output scantable |
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| 145 | overwrite : overwrite existing table |
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| 146 | """ |
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[2794] | 147 | out_default = "sbseparated.asap" |
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| 148 | if len(outname) == 0: |
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| 149 | outname = out_default |
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| 150 | asaplog.post() |
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| 151 | asaplog.push("The output file name is not specified.") |
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| 152 | asaplog.push("Using default name '%s'" % outname) |
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| 153 | asaplog.post("WARN") |
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[2647] | 154 | |
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[2794] | 155 | if os.path.exists(outname): |
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| 156 | if overwrite: |
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| 157 | asaplog.push("removing the old file '%s'" % outname) |
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| 158 | shutil.rmtree(outname) |
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| 159 | else: |
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| 160 | asaplog.post() |
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| 161 | asaplog.push("Output file '%s' already exists." % outname) |
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| 162 | asaplog.post("ERROR") |
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| 163 | return False |
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[2712] | 164 | |
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[2794] | 165 | self._separator.separate(outname) |
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[2647] | 166 | |
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