Tool: sdlinefinder tool for automated line search
Method: sdlinefinder Construct a sdlinefinder tool
Method: setoptions Set the parameters of the search algorithm
threshold double a single channel threshold default is sqrt(3), which means together with 3 minimum channels at least 3 sigma detection criterion. For bad baseline shape, threshold may need to be increased.
minnchan int minimum number of channels above the threshold to report a detection, default is 3
avglimit int perform the averaging of no more than avglimit adjacent channels to search for broad lines Default is 8, but for a bad baseline shape this parameter should be decreased (may be even down to a minimum of 1 to disable this option) to avoid confusing of baseline undulations with a real line. Setting a very large value doesn't usually provide valid detections.
boxsize double the box size for running mean calculation. Default is 1./5. of the whole spectrum size
Method: setscan Set the 'scantable' data to work with, associated mask (mask parameter) and the edge channel rejection (edge parameter)
scan any sdtable to work with
mask boolArray an optional mask retreived from sdtable
edge intArray an optional number of channel to drop. If edge has zero length, all channels chosen by mask will be used. If edge has one element only, it represents the number of channels to drop from both sides of the spectrum. edge is introduced for convinience, although all functionality can be achieved using a spectrum mask only
Method: findlines search for spectral lines for a row specified by whichRow and Beam/IF/Pol specified by current cursor set for the scantable. Number of lines found is returned.
whichRow int specified row
Method: getmask get the mask to mask out all lines that have been found (default)
invert bool If invert=true, only channels belong to lines will be unmasked. Note: all channels originally masked by the input mask (mask in setscan) or dropped out by the edge parameter (edge in setscan) are still excluded regardless on the invert option.
Method: getlineranges Get range for all lines found. The same units as used in the scan will be returned (e.g. velocity instead of channels).
Method: getlinerangesinchannels The same as getLineRanges, but channels are always used to specify the range.

-- WesYoung - 17 Jul 2006
Topic revision: r1 - 2006-07-17, WesYoung
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