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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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This code is available under the terms of the GNU General Public Lincense


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