I mean for identification (ie shorthand to identify the line in question) not for stating the measured wavelength. (I can measure that to a precision of up to 0.01A). In papers on astrophysics you only need to say for example Na 5890, Na 5896, He 6678, DIB 6613 etc for the reader to know the line you are talking about. That’s what I meant by avoiding the ugly decimal point.
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