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°2330".
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°MMSS"
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.