Skip to content

Commit

Permalink
Merge pull request #11 from mushrom/master
Browse files Browse the repository at this point in the history
Simplified UTMLetterDesignator()
stustison authored Jul 18, 2018
2 parents 459f23b + 45129b9 commit d254aab
Showing 1 changed file with 13 additions and 46 deletions.
59 changes: 13 additions & 46 deletions usng.js
Original file line number Diff line number Diff line change
@@ -499,54 +499,21 @@
***************************************************************************/

UTMLetterDesignator: function (lat) {
UTMLetterDesignator: function (lat){
lat = parseFloat(lat);

var letterDesignator;
if ((84 >= lat) && (lat >= 72))
letterDesignator = 'X';
else if ((72 > lat) && (lat >= 64))
letterDesignator = 'W';
else if ((64 > lat) && (lat >= 56))
letterDesignator = 'V';
else if ((56 > lat) && (lat >= 48))
letterDesignator = 'U';
else if ((48 > lat) && (lat >= 40))
letterDesignator = 'T';
else if ((40 > lat) && (lat >= 32))
letterDesignator = 'S';
else if ((32 > lat) && (lat >= 24))
letterDesignator = 'R';
else if ((24 > lat) && (lat >= 16))
letterDesignator = 'Q';
else if ((16 > lat) && (lat >= 8))
letterDesignator = 'P';
else if (( 8 > lat) && (lat >= 0))
letterDesignator = 'N';
else if (( 0 > lat) && (lat >= -8))
letterDesignator = 'M';
else if ((-8> lat) && (lat >= -16))
letterDesignator = 'L';
else if ((-16 > lat) && (lat >= -24))
letterDesignator = 'K';
else if ((-24 > lat) && (lat >= -32))
letterDesignator = 'J';
else if ((-32 > lat) && (lat >= -40))
letterDesignator = 'H';
else if ((-40 > lat) && (lat >= -48))
letterDesignator = 'G';
else if ((-48 > lat) && (lat >= -56))
letterDesignator = 'F';
else if ((-56 > lat) && (lat >= -64))
letterDesignator = 'E';
else if ((-64 > lat) && (lat >= -72))
letterDesignator = 'D';
else if ((-72 > lat) && (lat >= -80))
letterDesignator = 'C';
else
letterDesignator = 'Z'; // This is here as an error flag to show
// that the latitude is outside the UTM limits
return letterDesignator;
if (lat > 84 || lat < -80){
return 'Z';

} else {
var index = (lat + 80) / 8;

if (index >= 6) index++; // skip 'I'
if (index >= 12) index++; // skip 'O'
if (index >= 22) index--; // adjust for 80 to 84, which should be 'X'

return String.fromCharCode(67 /* C */ + index);
}
},


0 comments on commit d254aab

Please sign in to comment.