4 * Interface to man units(1), /usr/share/units.dat
7 * Definition: 9.6347558e+08 m^2
8 * $ units "372.0 mi2" m^2
9 * Definition: 9.6347558e+08 m^2
12 * CachedMarkup.php: Cached_SemanticLink::_expandurl()
13 * SemanticWeb.php: class SemanticAttributeSearchQuery
15 * Windows requires the cygwin /usr/bin/units.
16 * All successfully parsed unit definitions are stored in the wikidb,
17 * so that subsequent expansions will not require /usr/bin/units be called again.
18 * So far even on Windows (cygwin) the process is fast enough.
20 * TODO: understand dates and maybe times
21 * YYYY-MM-DD, "CW"ww/yy (CalendarWeek)
26 function __construct()
28 if (defined('DISABLE_UNITS') and DISABLE_UNITS)
30 elseif (defined("UNITS_EXE")) // ignore dynamic check
33 exec("units m2", $o, $this->errcode);
37 * $this->_attribute_base = $units->Definition($this->_attribute);
39 * @param string $query
42 function Definition($query)
44 static $Definitions = array();
45 if (isset($Definitions[$query])) return $Definitions[$query];
48 $query = preg_replace("/,/", "", $query);
49 if ($query == '' or $query == '*')
50 return ($Definitions[$query] = '');
51 // detect date values, currently only ISO: YYYY-MM-DD or YY-MM-DD
52 if (preg_match("/^(\d{2,4})-(\d{1,2})-(\d{1,2})$/", $query, $m)) {
53 $date = mktime(0, 0, 0, $m[2], $m[3], $m[1]);
54 return ($Definitions[$query] = "$date date");
56 if (preg_match("/^(\d{2,4})-(\d{1,2})-(\d{1,2}) (\d{1,2}):(\d{2}):?(\d{2})?$/", $query, $m)) {
57 $date = mktime($m[4], $m[5], @$m[6], $m[2], $m[3], $m[1]);
58 return ($Definitions[$query] = "$date date");
60 $def = $this->_cmd("\"$query\"");
61 if (preg_match("/Definition: (.+)$/", $def, $m))
62 return ($Definitions[$query] = $m[1]);
64 trigger_error("units: " . $def, E_USER_WARNING);
70 * We must ensure that the same baseunits are matched against.
71 * We cannot compare m^2 to m or ''
72 * $val_base = $this->_units->basevalue($value); // SemanticAttributeSearchQuery
74 * @param string $query
78 function basevalue($query, $def = false)
81 $def = $this->Definition($query);
83 if (is_numeric($def)) // e.g. "1 million"
85 if (preg_match("/^([-0-9].*) \w.*$/", $def, $m))
92 * $this->_unit = $units->baseunit($this->_attribute); // SemanticAttributeSearchQuery
93 * and Cached_SemanticLink::_expandurl()
95 * @param string $query
99 function baseunit($query, $def = false)
102 $def = $this->Definition($query);
104 if (preg_match("/ (.+)$/", $def, $m))
114 if (defined("UNITS_EXE")) {
115 $s = UNITS_EXE . " $args";
118 $result = `units $args`;
119 return trim($result);