Return Compass Ordinal Abbreviation From A Direction

This code will return a compass Intercardinal (or ordinal) direction based on a numeric direction. It supports the article here on returning a weather forecast with OpenWeatherMap. In some cases the cardinal directions or N, S, E, and W are suitable. Other times the 16 Intercardinal (NNE, NE, ENE etc.) are appropriate. We're returning a more full set of 32 secondary-intercardinal directions for the sake of accuracy.

By at least the middle of the eighteenth century the 32-point system had been further extended with the use of half- and quarter-points to give a total of 128 directions - this is well outside the comprehension of most people so we've avoided its use.

A 32 Point Compass Rose. Source: WikiPedia.

The 32 points on the compass rose are returned in our PHP code based upon the values from the following table on Wikipedia.

The 32 Points of a Compass. Source: WikiPedia.

PHP Code

When referenced by any of our shortcodes, the following should be copied into your custom functions file along with the shortcode function.

function beliefmedia_compass_cardinal($dir) {

$dir = abs($dir);

switch ($dir) {
case ($dir >= 354 && $dir < 6): $cardinal = 'N'; break; case ($dir >= 6 && $dir < 17): $cardinal = 'NbE'; break; case ($dir >= 17 && $dir < 28): $cardinal = 'NNE'; break; case ($dir >= 28 && $dir < 39): $cardinal = 'NEbN'; break; case ($dir >= 39 && $dir < 51): $cardinal = 'NE'; break; case ($dir >= 51 && $dir < 62): $cardinal = 'NEbE'; break; case ($dir >= 62 && $dir < 73): $cardinal = 'ENE'; break; case ($dir >= 73 && $dir < 84): $cardinal = 'EbN'; break; case ($dir >= 84 && $dir < 96): $cardinal = 'E'; break; case ($dir >= 96 && $dir < 107): $cardinal = 'EbS'; break; case ($dir >= 107 && $dir < 118): $cardinal = 'ESE'; break; case ($dir >= 118 && $dir < 129): $cardinal = 'SEbE'; break; case ($dir >= 129 && $dir < 141): $cardinal = 'SE'; break; case ($dir >= 141 && $dir < 152): $cardinal = 'SEbS'; break; case ($dir >= 152 && $dir < 163): $cardinal = 'SSE'; break; case ($dir >= 163 && $dir < 174): $cardinal = 'SbE'; break; case ($dir >= 174 && $dir < 186): $cardinal = 'S'; break; case ($dir >= 186 && $dir < 197): $cardinal = 'SbW'; break; case ($dir >= 197 && $dir < 208): $cardinal = 'SSW'; break; case ($dir >= 208 && $dir < 219): $cardinal = 'SWbS'; break; case ($dir >= 219 && $dir < 231): $cardinal = 'SW'; break; case ($dir >= 231 && $dir < 242): $cardinal = 'SWbW'; break; case ($dir >= 242 && $dir < 253): $cardinal = 'WSW'; break; case ($dir >= 253 && $dir < 264): $cardinal = 'WbS'; break; case ($dir >= 264 && $dir < 276): $cardinal = 'W'; break; case ($dir >= 276 && $dir < 287): $cardinal = 'WbN'; break; case ($dir >= 287 && $dir < 298): $cardinal = 'WNW'; break; case ($dir >= 298 && $dir < 309): $cardinal = 'NWbW'; break; case ($dir >= 309 && $dir < 321): $cardinal = 'NW'; break; case ($dir >= 321 && $dir < 332): $cardinal = 'NWbN'; break; case ($dir >= 332 && $dir < 343): $cardinal = 'NNW'; break; case ($dir >= 343 && $dir < 354): $cardinal = 'NbW'; break; } return $cardinal; }[/php] We'll likely update this post soon with a function to return just the 16-point Intercardinals. The following function returns the 16-point cardinal.

function beliefmedia_compass16_cardinal($deg) {

$cardinalDirections = array(
'N' => array(348.75, 360),
'N2' => array(0, 11.25),
'NNE' => array(11.25, 33.75),
'NE' => array(33.75, 56.25),
'ENE' => array(56.25, 78.75),
'E' => array(78.75, 101.25),
'ESE' => array(101.25, 123.75),
'SE' => array(123.75, 146.25),
'SSE' => array(146.25, 168.75),
'S' => array(168.75, 191.25),
'SSW' => array(191.25, 213.75),
'SW' => array(213.75, 236.25),
'WSW' => array(236.25, 258.75),
'W' => array(258.75, 281.25),
'WNW' => array(281.25, 303.75),
'NW' => array(303.75, 326.25),
'NNW' => array(326.25, 348.75)
);

foreach ($cardinalDirections as $dir => $angles) {
if ($deg >= $angles[0] && $deg < $angles[1]) { $cardinal = str_replace('2', '', $dir); } } return $cardinal; }[/php]