Convert degree

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Converting between sexagesimal and decimal degree notations

Converting from sexagesimal (DMS) to decimal degree notation

To convert from sexagesimal degree to decimal degree notation the degree value is kept, the minutes value is divided by 60, the seconds value is divided by 3600 and the results are summed. An example of a conversion of 12 degree 45 min 50 sec north (usually denotes as 12:45:50N):

    12 degree -> 12.00000 degree
    45 min / 60 -> 0.75000 degree
    50 sec / 3600 -> 0.01389 degree
    ---------------- addition of values ----------
    12.76389 degree (decimal degree notation)

Converting from decimal to sexagesimal degree notation

To convert from decimal degree to sexagesimal degree notation the calculation is done as illustrated by an example for a conversion of 12.7689 degree (decimal notation):

    12.76389 -> 12 degree, remainder 0.76389
    0.76389 * 60 -> 45 minutes, remainder 0.8334
    0.8334 * 60 -> 50 seconds
    ----------------------------------------------
    12:45:50N degree (sexagesimal degree notation)

The N for north has to be added to complete the sexagesimal notation, since the value is positive in decimal notation. GRASS supports both notations for latitude-longitude coordinate system.

See also