Calculator for celestial navigation (CN). Supports just the basic add/subtract of degrees and minutes using the typical notation just in celestial navigation. Most calculators support degrees/minutes-as-fraction (26°23.5'). But they show results in degrees/minutes/seconds (26°23'30". For celestial navigation, sight reduction using HO249 tables and almanacs uses DD°MM.F'. This calculator is aimed specifically at that use case and thus only operates with DD°MM.F' and not with DD°MM'SS" While navigators should do this math by hand, using a calculator while practicing, learning or to double check is useful. This does just that, no more.
