| 1 | import _asap |
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| 2 | |
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| 3 | class linefinder: |
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| 4 | """ |
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| 5 | The class for automated spectral line search in ASAP. |
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| 6 | """ |
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| 7 | |
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| 8 | def __init__(self): |
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| 9 | """ |
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| 10 | Create a line finder object. |
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| 11 | """ |
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| 12 | self.finder = _asap.linefinder() |
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| 13 | return |
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| 14 | |
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| 15 | def set_scan(self,scan,mask=None,edge=(0,0)): |
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| 16 | """ |
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| 17 | Set the 'data' (scantable) to work with. |
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| 18 | Parameters: |
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| 19 | scan: a scantable |
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| 20 | mask: an optional mask retreived from scantable |
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| 21 | edge: an optional number of channel to drop at |
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| 22 | the edge of spectrum. If only one value is |
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| 23 | specified, the same number will be dropped from |
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| 24 | both sides of the spectrum. Default is to keep |
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| 25 | all channels |
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| 26 | """ |
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| 27 | if not scan: |
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| 28 | raise RuntimeError, 'Please give a correct scan' |
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| 29 | if len(edge)>2: |
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| 30 | raise RuntimeError, "The edge parameter should have two \ |
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| 31 | or less elements" |
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| 32 | if mask is None: |
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| 33 | from numarray import ones |
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| 34 | self.finder.setscan(scan,ones(scan.nchan()),edge) |
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| 35 | else: |
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| 36 | self.finder.setscan(scan,mask,edge) |
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| 37 | return |
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| 38 | def find_lines(self): |
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| 39 | """ |
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| 40 | Search for spectral lines in the scan assigned in set_scan. |
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| 41 | A number of lines found will be returned |
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| 42 | """ |
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| 43 | return self.finder.findlines() |
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| 44 | def get_mask(self,invert=False): |
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| 45 | """ |
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| 46 | Get the mask to mask out all lines that have been found (default) |
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| 47 | |
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| 48 | Parameters: |
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| 49 | invert if True, only channels belong to lines will be unmasked |
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| 50 | |
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| 51 | Note: all channels originally masked by the input mask or |
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| 52 | dropped out by the edge parameter will still be excluded |
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| 53 | regardless on the invert option |
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| 54 | """ |
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| 55 | return self.finder.getmask(invert) |
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| 56 | def get_ranges(self,defunits=True): |
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| 57 | """ |
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| 58 | Get ranges (start and end channels or velocities) for all spectral |
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| 59 | lines found. |
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| 60 | |
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| 61 | Parameters: |
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| 62 | defunits if True (default), the range will use the same units |
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| 63 | as set for the scan (e.g. LSR velocity) |
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| 64 | if False, the range will be expressed in channels |
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| 65 | """ |
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| 66 | return self.finder.getlineranges(defunits) |
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