[101] | 1 | from scantable import scantable |
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| 2 | |
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[141] | 3 | def average_time(*args,**kwargs): |
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[101] | 4 | """ |
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[113] | 5 | Return the (time) average of a scan or list of scans. [in channels only] |
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| 6 | Parameters: |
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| 7 | one scan or comma separated scans |
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| 8 | mask: an optional mask |
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| 9 | Example: |
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| 10 | # return a time averaged scan from scana and scanb |
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| 11 | # without using a mask |
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[129] | 12 | scanav = average_time(scana,scanb) |
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[113] | 13 | # return the (time) averaged scan, i.e. the average of |
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| 14 | # all correlator cycles |
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| 15 | scanav = average_time(scan) |
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| 16 | |
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[101] | 17 | """ |
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[113] | 18 | lst = args |
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[101] | 19 | if len(args) < 2: |
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[113] | 20 | if type(args[0]) is list: |
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| 21 | if len(args[0]) < 2: |
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| 22 | print "Please give at least two scantables" |
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| 23 | return |
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| 24 | else: |
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| 25 | s = args[0] |
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| 26 | if s.nrow() > 1: |
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| 27 | from asap._asap import average as _av |
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| 28 | return scantable(_av(s)) |
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| 29 | else: |
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| 30 | print "Given scantable is already time averaged" |
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| 31 | return |
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| 32 | lst = tuple(args[0]) |
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| 33 | else: |
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| 34 | lst = tuple(args) |
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| 35 | from asap._asap import averages as _avs |
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| 36 | d = [lst[0].nbeam(),lst[0].nif(),lst[0].npol(),lst[0].nchan()] |
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| 37 | for s in lst: |
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[101] | 38 | if not isinstance(s,scantable): |
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| 39 | print "Please give a list of scantables" |
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| 40 | return |
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| 41 | dim = [s.nbeam(),s.nif(),s.npol(),s.nchan()] |
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| 42 | if (dim != d): |
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| 43 | print "All scans have to have the same numer of Beams/IFs/Pols/Chans" |
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| 44 | return |
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| 45 | if kwargs.has_key('mask'): |
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[113] | 46 | return scantable(_avs(lst, kwargs.get('mask'))) |
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[101] | 47 | else: |
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| 48 | from numarray import ones |
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[113] | 49 | mask = tuple(ones(d[3])) |
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| 50 | return scantable(_avs(lst, mask)) |
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[101] | 51 | |
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| 52 | def quotient(source, reference): |
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| 53 | """ |
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| 54 | Return the quotient of a 'source' scan and a 'reference' scan |
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| 55 | Parameters: |
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| 56 | source: the 'on' scan |
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| 57 | reference: the 'off' scan |
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| 58 | """ |
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| 59 | from asap._asap import quotient as _quot |
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| 60 | return scantable(_quot(source, reference)) |
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| 61 | |
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[141] | 62 | def scale(scan, factor, insitu=False): |
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[101] | 63 | """ |
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| 64 | Return a scan where all spectra are scaled by the give 'factor' |
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| 65 | Parameters: |
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| 66 | scan: a scantable |
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[113] | 67 | factor: the scaling factor |
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[101] | 68 | Note: |
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| 69 | This currently applies the all beams/IFs/pols |
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| 70 | """ |
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[141] | 71 | if not insitu: |
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| 72 | from asap._asap import scale as _scale |
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| 73 | return scantable(_scale(scan, factor)) |
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| 74 | else: |
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| 75 | from asap._asap import scale_insitu as _scale |
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| 76 | _scale(scan, factor) |
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| 77 | return |
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| 78 | |
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[101] | 79 | |
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[113] | 80 | def add(scan, offset): |
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| 81 | """ |
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| 82 | Return a scan where the offset is added. |
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| 83 | Parameters: |
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| 84 | scan: a scantable |
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| 85 | offset: the value to add |
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| 86 | Note: |
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| 87 | This currently applies the all beams/IFs/pols |
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| 88 | """ |
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| 89 | from asap._asap import add as _add |
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| 90 | return scantable(_add(scan, offset)) |
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[101] | 91 | |
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[113] | 92 | |
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[101] | 93 | def bin(scan, binwidth=5): |
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| 94 | """ |
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| 95 | """ |
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| 96 | from asap._asap import bin as _bin |
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| 97 | return scantable(_bin(scan, binwidth)) |
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[113] | 98 | |
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| 99 | def average_pol(scan, mask=None): |
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| 100 | """ |
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| 101 | Average the Polarisations together. |
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| 102 | Parameters: |
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| 103 | scan - a scantable |
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| 104 | mask - an optional mask defining the region, where |
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| 105 | the averaging will be applied. The output |
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| 106 | will have all specified points masked. |
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| 107 | The dimension won't be reduced and |
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| 108 | all polarisations will contain the |
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| 109 | averaged spectrum. |
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| 110 | Example: |
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| 111 | polav = average_pols(myscan) |
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| 112 | """ |
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| 113 | from asap._asap import averagepol as _avpol |
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| 114 | from numarray import ones |
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| 115 | if mask is None: |
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| 116 | mask = tuple(ones(scan.nchan())) |
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| 117 | return scantable(_avpol(scan, mask)) |
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| 118 | |
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| 119 | def hanning(scan): |
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| 120 | """ |
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| 121 | Hanning smooth the channels. |
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| 122 | Parameters: |
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| 123 | scan - the input scan |
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| 124 | Example: |
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| 125 | none |
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| 126 | """ |
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| 127 | from asap._asap import hanning as _han |
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| 128 | return scantable(_han(scan)) |
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| 129 | |
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| 130 | |
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| 131 | def poly_baseline(scan, mask=None, order=0): |
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| 132 | """ |
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| 133 | Return a scan which has been baselined by a polynomial. |
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| 134 | Parameters: |
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| 135 | scan: a scantable |
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| 136 | mask: an optional mask |
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| 137 | order: the order of the polynomial (default is 0) |
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| 138 | Example: |
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| 139 | # return a scan baselined by a third order polynomial, |
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| 140 | # not using a mask |
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| 141 | bscan = poly_baseline(scan, order=3) |
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| 142 | """ |
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| 143 | from asap.asapfitter import fitter |
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| 144 | if mask is None: |
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| 145 | from numarray import ones |
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| 146 | mask = tuple(ones(scan.nchan())) |
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| 147 | f = fitter() |
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| 148 | f._verbose(True) |
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| 149 | f.set_scan(scan, mask) |
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| 150 | f.set_function(poly=order) |
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| 151 | sf = f.auto_fit() |
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| 152 | return sf |
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