##############################################################################
#
# Maidenhead Locator calculator
#
# Convert a longitude/latitude coordinate to Maidenhead Locator
#
# Copyright (C) 2012-2025 Christophe DAVID ( ON6ZQ | AC6ZQ )
#
# This program is free software; you can redistribute it and/or modify it
# under the terms of the GNU General Public License version 2 as published
# by the Free Software Foundation (http://www.gnu.org/licenses/gpl.html).
#
##############################################################################

clear;
clc;

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# Convert latitude and longitude to Maidenhead Locator
function locator = MaidenheadLocator(latitude, longitude)

    locator = "";

    if latitude > -90 && latitude < 90 && longitude > -180 && longitude < 180

        longitude2 = longitude + 180;
        latitude2 = latitude + 90;

        lon1 = floor(longitude2 / 20);
        lat1 = floor(latitude2 / 10);

        lon2 = floor(mod(longitude2 / 2, 10));
        lat2 = floor(mod(latitude2, 10));

        lon3 = 60 * (longitude2 - 2 * floor(longitude2 / 2));
        lat3 = 60 * (latitude2 - floor(latitude2));

        lon4 = floor(lon3 / 5);
        lat4 = floor(lat3 / 2.5);

        locator = [char(65 + lon1), char(65 + lat1), ...
                   char(48 + lon2), char(48 + lat2), ...
                   char(97 + lon4), char(97 + lat4)];
    end

endfunction

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# Test cases
assert(strcmp(MaidenheadLocator( 48.14666 , 11.60833 ), "JN58td"));
assert(strcmp(MaidenheadLocator( -34.91 , -56.21166 ), "GF15vc"));
assert(strcmp(MaidenheadLocator( 41.714775 , -72.727260 ), "FN31pr"));
assert(strcmp(MaidenheadLocator( 37.413708 , -122.1073236 ), "CM87wj"));
assert(strcmp(MaidenheadLocator( 59.19222 , -115.5925 ), "DO29ee"));
assert(strcmp(MaidenheadLocator( -51.6922 , -58.8349 ), "GD08nh"));
assert(strcmp(MaidenheadLocator( 45.8325 , 6.8644 ), "JN35kt"));
assert(strcmp(MaidenheadLocator( -35.65944 , 148.79 ), "QF44ji"));

##############################################################################
# Example output
InputLatitude = 45.8325;
InputLongitude = 6.8644;
printf("\n%f, %f => %s\n", InputLatitude, InputLongitude, ...
        MaidenheadLocator(InputLatitude, InputLongitude));

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