define_tag(
	'bearing',
	-namespace='math_',
	-req='d', -copy,
	-priority='replace',
	-description='Returns a general compass bearing (i.e. NNW) given degrees.'
);
	// convert to decimal
	local('d') = decimal(#d)->setformat( -precision=1)&;

	// degrees between points	
	local('i') = (360.0/16.0);

	// restrict to valid degrees
	fail_if(
		(#d > 360 || #d < -360), -1,
		'[math_bearing] requires a value between -360 and 360 degrees.'
	);

	// convert negative degrees
	#d < 0 ? #d = 360 + #d;

	// catch due north
	#d == 0 || #d == 360 ? return('N');

	// compass points
	local('pts') = treemap(
		0.0		=	'N',
		22.5		=	'NNE',
		45.0		=	'NE',
		67.5		=	'ENE',
		90.0		=	'E',
		112.5	=	'ESE',
		135.0	=	'SE',
		157.5	=	'SSE',
		180.0	=	'S',
		202.5	=	'SSW',
		225.0	=	'SW',
		247.5	=	'WSW',
		270.0	=	'W',
		292.5	=	'WNW',
		315.0	=	'NW',
		337.5	=	'NNW',
		360.0	=	'N'
	);

	// round to nearest point and look up
	local('b') = #pts->find(math_roundto(#d,#i));

	return(#b);
/define_tag;