[RM-8171] [variable LSF and linemodel] error issued when LSF lambda range is equal to spectrum range

Created on 2023-07-05 16:50:49 by Didier Vibert. % Done: 100

It happens in hybrid fit when determining overlapping elements: if one of the line inside an element is outside the range, it is still trying to determine the overlap but it cannot compute the line width because the LSF is not available => should only consider lines inside range