5.1.7.0 sd.simplelinefinder.find_lines

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sd.simplelinefinder.find_lines - Function

5.1.7 Search for spectral lines in the spectrum
Description

A simple spectral line detection routine, which assumes that bandpass has been taken out perfectly and no channels are flagged within the spectrum. A detection is reported if consequtive minchan number of channels is consistently above or below the median value. The threshold is given in terms of the rms calculated using 80% of the lowest data points by the absolute value (with respect to median).

This method returns a list of tuples each containing start and stop 0-based channel number of every detected line. Empty list if nothing has been detected.

Note. The median and rms about this median is stored inside this class and can be obtained with rms and median methods.

Arguments


Inputs
spc	a list or tuple with the spectrum, no default
	allowed:	tuple
	Default:
edge	detection threshold
	allowed:	intger
	Default:	0
minchan	minimum number of consequitive channels exceeding threshold to claim the detection
	allowed:	integer
	Default:	3
tailsearch	if True (default), the algorithm attempts to widen each line until its flux crosses the median. It merges lines if necessary
	allowed:	bool
	Default:	True
splitFeatures	if True, the algorithm attempts to split each detected spectral feature into a number of spectral lines (just one local extremum)
	allowed:	bool
	Default:	False

Returns
list of tuples that indicates ranges of detected lines

Example

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