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phpweather.php
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phpweather.php
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<?php
////////////////////////////////////////////
/* Copied from PHP Weather version 1.62. */
/* Line 109 was added for php timeclock. */
/* Line 110 was edited for php timeclock. */
////////////////////////////////////////////
/* Unsets old language variables and loads new ones. */
if (isset($strings)) {
/* The strings array is loaded - assume the same for the rest. */
unset($strings);
unset($wind_dir_text_short_array);
unset($wind_dir_text_array);
unset($weather_array);
unset($cloud_condition_array);
}
/* Load the new strings */
$wind_dir_text_short_array = array(
'N',
'N/NE',
'NE',
'E/NE',
'E',
'E/SE',
'SE',
'S/SE',
'S',
'S/SW',
'SW',
'W/SW',
'W',
'W/NW',
'NW',
'N/NW',
'N');
$cloud_condition_array = array(
'SKC' => 'Clear',
'CLR' => 'Clear',
'VV' => 'Vertical Visibility',
'FEW' => 'Partly Cloudy',
'SCT' => 'Scattered Clouds',
'BKN' => 'Partly Cloudy',
'OVC' => 'Overcast');
/* Offset in hours to add to the time of a report. If all your times
* are 2 hours off, then set this to -2. */
$weather_offset = 0;
/* Make a connection to the MySQL database: */
if (mysql_pconnect($db_hostname, $db_username, $db_password)) {
mysql_select_db($db_name);
} else {
echo "<p>Unable to connect to MySQL database!</p>";
}
function store_speed($value, $windunit, &$meterspersec, &$knots, &$milesperhour) {
/*
* Helper function to convert and store speed based on unit.
* &$meterspersec, &$knots and &$milesperhour are passed on
* reference
*/
if ($windunit == 'KT') {
/* The windspeed measured in knots: */
$knots = number_format($value);
/* The windspeed measured in meters per second, rounded to one
* decimal place: */
$meterspersec = number_format($value * 0.51444, 1);
/* The windspeed measured in miles per hour, rounded to one
* decimal place: */
$milesperhour = number_format($value * 1.1507695060844667, 1);
} elseif ($windunit == 'MPS') {
/* The windspeed measured in meters per second: */
$meterspersec = number_format($value);
/* The windspeed measured in knots, rounded to one decimal
* place: */
$knots = number_format($value / 0.51444, 1);
/* The windspeed measured in miles per hour, rounded to one
* decimal place: */
$milesperhour = number_format($value / 0.51444 * 1.1507695060844667, 1);
} elseif ($windunit == 'KMH') {
/* The windspeed measured in kilometers per hour: */
$meterspersec = number_format($value * 1000 / 3600, 1);
$knots = number_format($value * 1000 / 3600 / 0.51444, 1);
/* The windspeed measured in miles per hour, rounded to one
* decimal place: */
$milesperhour = number_format($knots * 1.1507695060844667, 1);
}
}
function get_metar($station, $always_use_cache = 0) {
/*
* Looks in the database, and fetches a new metar is nesceary. If
* $always_use_cache is true, then it ignores the timestamp of the
* METAR and just returns it.
*
* You should pass a ICAO station identifier, eg. 'EKYT' for
* Aalborg, Denmark.
*/
global $conn, $dbmMetar, $dbmTimestamp, $db_prefix;
$query = "SELECT metar, UNIX_TIMESTAMP(timestamp) FROM " . $db_prefix . "metars WHERE station = '$station'";
$result = mysql_query($query);
@$metar_rows = mysql_num_rows($result); /* this suppresses a php error message if the metars db has not yet been created. */
if (isset($metar_rows)) { /* found station */
list($metar, $timestamp) = mysql_fetch_row($result);
}
if (isset($metar)) { /* found station */
if ($always_use_cache || $timestamp > time() - 3600) {
/* We have asked explicit for a cached metar, or the metar is
* still fresh. */
return $metar;
} else {
/* We looked in the cache, but the metar was too old. */
return fetch_metar($station, 0);
}
} else {
/* The station is new - we fetch a new METAR */
return fetch_metar($station, 1);
}
}
function fetch_metar($station, $new) {
/*
* Fetches a new METER from weather.noaa.gov. If the $new variable
* is true, the metar is inserted, else it will replace the old
* metar. The new METAR is returned.
*/
global $conn, $dbmMetar, $dbmTimestamp;
$metar = '';
$station = strtoupper($station);
/* We use the @ notation, because it might fail. */
$file = @file('http://weather.noaa.gov/pub/data/' .
"observations/metar/stations/$station.TXT");
/* Here we test to see if we actually got a METAR. */
if (is_array($file)) {
$date = trim($file[0]);
$metar = trim($file[1]);
for ($i = 2; $i < count($file); $i++) {
$metar .= ' ' . trim($file[i]);
}
/* The date is in the form 2000/10/09 14:50 UTC. This seperates
the different parts. */
$date_parts = explode(':', strtr($date, '/ ', '::'));
$date_unixtime = gmmktime($date_parts[3], $date_parts[4],
0, $date_parts[1], $date_parts[2],
$date_parts[0]);
if (!ereg('[0-9]{6}Z', $metar)) {
/* Some reports dont even have a time-part, so we insert the
* current time. This might not be the time of the report, but
* it was broken anyway :-) */
$metar = gmdate('dHi', $date_unixtime) . 'Z ' . $metar;
}
if ($date_unixtime < (time() - 3300)) {
/* The timestamp in the metar is more than 55 minutes old. We
* adjust the timestamp, so that we won't try to fetch a new
* METAR within the next 5 minutes. After 5 minutes, the
* timestamp will again be more than 1 hour old. */
$date_unixtime = time() - 3300;
}
} else {
/* If we end up here, it means that there was no file, we then set
* the metar to and empty string. We set the date to time() - 3000
* to give the server 10 minutes of peace. If the file is
* unavailable, we don't want to stress the server. */
$metar = '';
$date_unixtime = time() - 3000;
}
/* It might seam strange, that we make a local date, but MySQL
* expects a local when we insert the METAR. */
$date = date('Y/m/d H:i', $date_unixtime);
if ($new) {
/* Insert the new record */
$query = "INSERT INTO " . $db_prefix . "metars SET station = '$station', " .
"metar = '$metar', timestamp = '$date'";
} else {
/* Update the old record */
$query = "UPDATE " . $db_prefix . "metars SET metar = '$metar', " .
"timestamp = '$date' WHERE station = '$station'";
}
mysql_query($query);
return $metar;
}
function process_metar($metar) {
/* This function decodes a raw METAR. The result is an associative
* array with entries like 'temp_c', 'visibility_miles' etc. */
global $strings, $wind_dir_text_short_array, $wind_dir_text_array,
$cloud_condition_array, $weather_array, $weather_offset;
$temp_visibility_miles = '';
$cloud_layers = 0;
$decoded_metar['remarks'] = '';
$decoded_metar['weather'] = '';
$cloud_coverage = array('SKC' => '0',
'CLR' => '0',
'VV' => '8/8',
'FEW' => '1/8 - 2/8',
'SCT' => '3/8 - 4/8',
'BKN' => '5/8 - 7/8',
'OVC' => '8/8');
$decoded_metar['metar'] = $metar;
$parts = split('[ ]+', $metar);
$num_parts = count($parts);
for ($i = 0; $i < $num_parts; $i++) {
$part = $parts[$i];
if (ereg('RMK|TEMPO|BECMG', $part)) {
/* The rest of the METAR is either a remark or temporary
* information. We skip the rest of the METAR. */
$decoded_metar['remarks'] .= ' ' . $part;
break;
} elseif ($part == 'METAR') {
/*
* Type of Report: METAR
*/
$decoded_metar['type'] = 'METAR';
} elseif ($part == 'SPECI') {
/*
* Type of Report: SPECI
*/
$decoded_metar['type'] = 'SPECI';
} elseif (ereg('^[A-Z]{4}$', $part) && !isset($decoded_metar['station'])) {
/*
* Station Identifier
*/
$decoded_metar['station'] = $part;
} elseif (ereg('([0-9]{2})([0-9]{2})([0-9]{2})Z', $part, $regs)) {
/*
* Date and Time of Report
* We return a standard Unix UTC/GMT timestamp suitable for
* gmdate()
*/
$decoded_metar['time'] = gmmktime($regs[2] + $weather_offset, $regs[3], 0,
gmdate('m'), $regs[1], gmdate('Y'));
} elseif (ereg('(AUTO|COR|RTD|CC[A-Z]|RR[A-Z])', $part, $regs)) {
/*
* Report Modifier: AUTO, COR, CCx or RRx
*/
$decoded_metar['report_mod'] = $regs[1];
} elseif (ereg('([0-9]{3}|VRB)([0-9]{2,3}).*(KT|MPS|KMH)', $part, $regs)) {
/* Wind Group */
$windunit = $regs[3]; /* do ereg in two parts to retrieve unit first */
/* now do ereg to get the actual values */
ereg("([0-9]{3}|VRB)([0-9]{2,3})(G([0-9]{2,3})?$windunit)", $part, $regs);
if ($regs[1] == 'VRB') {
$decoded_metar['wind_deg'] = $strings['wind_vrb_long'];
$decoded_metar['wind_dir_text'] = $strings['wind_vrb_long'];
$decoded_metar['wind_dir_text_short'] = $strings['wind_vrb_short'];
} else {
$decoded_metar['wind_deg'] = $regs[1];
$decoded_metar['wind_dir_text'] =
$wind_dir_text_array[intval(round($regs[1] / 22.5))];
$decoded_metar['wind_dir_text_short'] =
$wind_dir_text_short_array[intval(round($regs[1] / 22.5))];
}
store_speed($regs[2],
$windunit,
$decoded_metar['wind_meters_per_second'],
$decoded_metar['wind_knots'],
$decoded_metar['wind_miles_per_hour']);
if (isset($regs[4])) {
/* We have a report with information about the gust. First we
have the gust measured in knots: */
store_speed($regs[4], $windunit,
$decoded_metar['wind_gust_meters_per_second'],
$decoded_metar['wind_gust_knots'],
$decoded_metar['wind_gust_miles_per_hour']);
}
} elseif (ereg('^([0-9]{3})V([0-9]{3})$', $part, $regs)) {
/*
* Variable wind-direction
*/
$decoded_metar['wind_var_beg'] = $regs[1];
$decoded_metar['wind_var_end'] = $regs[2];
} elseif ($part == 9999) {
/* A strange value. When you look at other pages you see it
interpreted like this (where I use > to signify 'Greater
than'): */
$decoded_metar['visibility_miles'] = '>6.2';
$decoded_metar['visibility_km'] = '>10';
} elseif (ereg('^([0-9]{4})$', $part, $regs)) {
/*
* Visibility in meters (4 digits only)
*/
$decoded_metar['visibility_km'] = number_format($regs[1] / 1000, 1);
$decoded_metar['visibility_miles'] =
number_format(($regs[1] / 1000) / 1.609344, 1);
} elseif (ereg('^[0-9]$', $part)) {
/*
* Temp Visibility Group, single digit followed by space
*/
$temp_visibility_miles = $part;
} elseif (ereg('^M?(([0-9]?)[ ]?([0-9])(/?)([0-9]*))SM$',
$temp_visibility_miles . ' ' .
$parts[$i], $regs)
) {
/*
* Visibility Group
*/
if ($regs[4] == '/') {
$vis_miles = $regs[2] + $regs[3] / $regs[5];
} else {
$vis_miles = $regs[1];
}
if ($regs[0][0] == 'M') {
/* The visibility measured in miles, prefixed with < to
indicate 'Less than' */
$decoded_metar['visibility_miles'] =
'<' . number_format($vis_miles, 1);
/* The visibility measured in kilometers. The value is rounded
to one decimal place, prefixed with < to indicate 'Less
than' */
$decoded_metar['visibility_km'] =
'<' . number_format($vis_miles * 1.609344, 1);
} else {
/* The visibility measured in mile.s */
$decoded_metar['visibility_miles'] = number_format($vis_miles, 1);
/* The visibility measured in kilometers, rounded to one
decimal place. */
$decoded_metar['visibility_km'] =
number_format($vis_miles * 1.609344, 1);
}
} elseif ($part == 'CAVOK') {
/* CAVOK: Used when the visibility is greather than 10
kilometers, the lowest cloud-base is at 5000 feet and there
is no significant weather. */
$decoded_metar['visibility_km'] = '>10';
$decoded_metar['visibility_miles'] = '>6.2';
$decoded_metar['cloud_layer1_condition'] = 'CAVOK';
} elseif (ereg('^R([0-9][0-9][RLC]?)/([MP]?[0-9]{4})V?(P?[0-9]{4})?F?T?$', $part, $regs)) {
$decoded_metar['runway_nr'] = $regs[1];
if ($regs[3]) {
/* We have both min and max visibility. */
$prefix = '';
if ($regs[2][0] == 'M') {
/* Less than. */
$prefix = '<';
$regs[2] = substr($regs[2], 1);
}
$decoded_metar['runway_vis_min_ft'] = $prefix . number_format($regs[2]);
$decoded_metar['runway_vis_min_meter'] = $prefix . number_format($regs[2] * 0.3048);
$prefix = '';
if ($regs[3][0] == 'P') {
/* Greather than. */
$prefix = '>';
$regs[3] = substr($regs[3], 1);
}
$decoded_metar['runway_vis_max_ft'] = $prefix . number_format($regs[3]);
$decoded_metar['runway_vis_max_meter'] = $prefix . number_format($regs[3] * 0.3048);
} else {
/* We only have a single visibility. */
$prefix = '';
if ($regs[2][0] == 'M') {
$prefix = '<';
$regs[2] = substr($regs[2], 1);
} elseif ($regs[2][0] == 'P') {
$prefix = '>';
$regs[2] = substr($regs[2], 1);
}
$decoded_metar['runway_vis_ft'] = $prefix . number_format($regs[2]);
$decoded_metar['runway_vis_meter'] = $prefix . number_format($regs[2] * 0.3048);
}
} elseif (ereg('^(-|\+|VC)?(TS|SH|FZ|BL|DR|MI|BC|PR|RA|DZ|SN|SG|GR|' .
'GS|PE|IC|UP|BR|FG|FU|VA|DU|SA|HZ|PY|PO|SQ|FC|SS|DS)+$',
$part)
) {
/*
* Current weather-group
*/
if ($part[0] == '-') {
/* A light phenomenon */
$decoded_metar['weather'] .= $strings['light'];
$part = substr($part, 1);
} elseif ($part[0] == '+') {
/* A heavy phenomenon */
$decoded_metar['weather'] .= $strings['heavy'];
$part = substr($part, 1);
} elseif ($part[0] . $part[1] == 'VC') {
/* Proximity Qualifier */
$decoded_metar['weather'] .= $strings['nearby'];
$part = substr($part, 2);
} else {
/* no intensity code => moderate phenomenon */
$decoded_metar['weather'] .= $strings['moderate'];
}
while ($bite = substr($part, 0, 2)) {
/* Now we take the first two letters and determine what they
mean. We append this to the variable so that we gradually
build up a phrase. */
$decoded_metar['weather'] .= $weather_array[$bite];
/* Here we chop off the two first letters, so that we can take
a new bite at top of the while-loop. */
$part = substr($part, 2);
}
} elseif (ereg('(SKC|CLR)', $part, $regs)) {
/*
* Cloud-layer-group.
* There can be up to three of these groups, so we store them as
* cloud_layer1, cloud_layer2 and cloud_layer3.
*/
$cloud_layers++;
/* Again we have to translate the code-characters to a
meaningful string. */
$decoded_metar['cloud_layer' . $cloud_layers . '_condition'] =
$cloud_condition_array[$regs[1]];
$decoded_metar['cloud_layer' . $cloud_layers . '_coverage'] =
$cloud_coverage[$regs[1]];
} elseif (ereg('^(VV|FEW|SCT|BKN|OVC)([0-9]{3})(CB|TCU)?$',
$part, $regs)
) {
/* We have found (another) a cloud-layer-group. There can be up
to three of these groups, so we store them as cloud_layer1,
cloud_layer2 and cloud_layer3. */
$cloud_layers++;
/* Again we have to translate the code-characters to a
meaningful string. */
if ($regs[1] == 'OVC') {
$clouds_str_temp = '';
} else {
$clouds_str_temp = $strings['clouds'];
}
if ($regs[3] == 'CB') {
/* cumulonimbus (CB) clouds were observed. */
$decoded_metar['cloud_layer' . $cloud_layers . '_condition'] =
$cloud_condition_array[$regs[1]] . $strings['clouds_cb'];
} elseif ($regs[3] == 'TCU') {
/* towering cumulus (TCU) clouds were observed. */
$decoded_metar['cloud_layer' . $cloud_layers . '_condition'] =
$cloud_condition_array[$regs[1]] . $strings['clouds_tcu'];
} else {
$decoded_metar['cloud_layer' . $cloud_layers . '_condition'] =
$cloud_condition_array[$regs[1]] . $clouds_str_temp;
}
$decoded_metar['cloud_layer' . $cloud_layers . '_coverage'] =
$cloud_coverage[$regs[1]];
$decoded_metar['cloud_layer' . $cloud_layers . '_altitude_ft'] =
$regs[2] * 100;
$decoded_metar['cloud_layer' . $cloud_layers . '_altitude_m'] =
round($regs[2] * 30.48);
} elseif (ereg('^(M?[0-9]{2})/(M?[0-9]{2})?$', $part, $regs)) {
/*
* Temperature/Dew Point Group
* The temperature and dew-point measured in Celsius.
*/
$decoded_metar['temp_c'] = number_format(strtr($regs[1], 'M', '-'));
$decoded_metar['dew_c'] = number_format(strtr($regs[2], 'M', '-'));
/* The temperature and dew-point measured in Fahrenheit, rounded
to the nearest degree. */
$decoded_metar['temp_f'] = round(strtr($regs[1], 'M', '-') * (9 / 5) + 32);
$decoded_metar['dew_f'] = round(strtr($regs[2], 'M', '-') * (9 / 5) + 32);
} elseif (ereg('A([0-9]{4})', $part, $regs)) {
/*
* Altimeter
* The pressure measured in inHg
*/
$decoded_metar['altimeter_inhg'] = number_format($regs[1] / 100, 2);
/* The pressure measured in mmHg, hPa and atm */
$decoded_metar['altimeter_mmhg'] = number_format($regs[1] * 0.254, 1);
$decoded_metar['altimeter_hpa'] = number_format($regs[1] * 0.33863881578947);
$decoded_metar['altimeter_atm'] = number_format($regs[1] * 3.3421052631579e-4, 3);
} elseif (ereg('Q([0-9]{4})', $part, $regs)) {
/*
* Altimeter
* This is strange, the specification doesnt say anything about
* the Qxxxx-form, but it's in the METARs.
*/
/* The pressure measured in hPa */
$decoded_metar['altimeter_hpa'] = number_format($regs[1]);
/* The pressure measured in mmHg, inHg and atm */
$decoded_metar['altimeter_mmhg'] = number_format($regs[1] * 0.7500616827, 1);
$decoded_metar['altimeter_inhg'] = number_format($regs[1] * 0.0295299875, 2);
$decoded_metar['altimeter_atm'] = number_format($regs[1] * 9.869232667e-4, 3);
} elseif (ereg('^T([0-9]{4})([0-9]{4})', $part, $regs)) {
/*
* Temperature/Dew Point Group, coded to tenth of degree.
* The temperature and dew-point measured in Celsius.
*/
store_temp($regs[1], $decoded_metar, 'temp_c', 'temp_f');
store_temp($regs[2], $decoded_metar, 'dew_c', 'dew_f');
} elseif (ereg('^T([0-9]{4}$)', $part, $regs)) {
store_temp($regs[1], $decoded_metar, 'temp_c', 'temp_f');
} elseif (ereg('^1([0-9]{4}$)', $part, $regs)) {
/*
* 6 hour maximum temperature Celsius, coded to tenth of degree
*/
store_temp($regs[1], $decoded_metar, 'temp_max6h_c', 'temp_max6h_f');
} elseif (ereg('^2([0-9]{4}$)', $part, $regs)) {
/*
* 6 hour minimum temperature Celsius, coded to tenth of degree
*/
store_temp($regs[1], $decoded_metar, 'temp_min6h_c', 'temp_min6h_f');
} elseif (ereg('^4([0-9]{4})([0-9]{4})$', $part, $regs)) {
/*
* 24 hour maximum and minimum temperature Celsius, coded to
* tenth of degree
*/
store_temp($regs[1], $decoded_metar, 'temp_max24h_c', 'temp_max24h_f');
store_temp($regs[2], $decoded_metar, 'temp_min24h_c', 'temp_min24h_f');
} elseif (ereg('^P([0-9]{4})', $part, $regs)) {
/*
* Precipitation during last hour in hundredths of an inch
* (store as inches)
*/
$decoded_metar['precip_in'] = number_format($regs[1] / 100, 2);
$decoded_metar['precip_mm'] = number_format($regs[1] * 0.254, 2);
} elseif (ereg('^6([0-9]{4})', $part, $regs)) {
/*
* Precipitation during last 3 or 6 hours in hundredths of an
* inch (store as inches)
*/
$decoded_metar['precip_6h_in'] = number_format($regs[1] / 100, 2);
$decoded_metar['precip_6h_mm'] = number_format($regs[1] * 0.254, 2);
} elseif (ereg('^7([0-9]{4})', $part, $regs)) {
/*
* Precipitation during last 24 hours in hundredths of an inch
* (store as inches)
*/
$decoded_metar['precip_24h_in'] = number_format($regs[1] / 100, 2);
$decoded_metar['precip_24h_mm'] = number_format($regs[1] * 0.254, 2);
} elseif (ereg('^4/([0-9]{3})', $part, $regs)) {
/*
* Snow depth in inches
*/
$decoded_metar['snow_in'] = number_format($regs[1]);
$decoded_metar['snow_mm'] = number_format($regs[1] * 25.4);
} else {
/*
* If we couldn't match the group, we assume that it was a
* remark.
*/
$decoded_metar['remarks'] .= ' ' . $part;
}
}
/*
* Relative humidity
*/
$decoded_metar['rel_humidity'] = number_format(pow(10,
(1779.75 * ($decoded_metar['dew_c'] - $decoded_metar['temp_c']) /
((237.3 + $decoded_metar['dew_c']) * (237.3 + $decoded_metar['temp_c']))
+ 2)), 1);
/*
* Humidity index
*/
$e = 6.112 * pow(10, 7.5 * $decoded_metar['temp_c']
/ (237.7 + $decoded_metar['temp_c']))
* $decoded_metar['rel_humidity'] / 100;
$decoded_metar['humidex_c'] =
number_format($decoded_metar['temp_c'] + 5 / 9 * ($e - 10), 1);
$decoded_metar['humidex_f'] =
number_format($decoded_metar['humidex_c'] * 9 / 5 + 32, 1);
/*
* Windchill.
*
* This is only appropriate if temp < 40f and windspeed > 3 mph
*/
if ($decoded_metar['temp_f'] <= '40' &&
$decoded_metar['wind_miles_per_hour'] > '3'
) {
$decoded_metar['windchill_f'] =
number_format(35.74 + 0.6215 * $decoded_metar['temp_f'] -
35.75 * pow((float)$decoded_metar['wind_miles_per_hour'], 0.16) +
0.4275 * $decoded_metar['temp_f'] *
pow((float)$decoded_metar['wind_miles_per_hour'], 0.16));
$decoded_metar['windchill_c'] =
number_format(13.112 + 0.6215 * $decoded_metar['temp_c'] -
13.37 * pow(($decoded_metar['wind_miles_per_hour'] / 1.609), 0.16) +
0.3965 * $decoded_metar['temp_c'] *
pow(($decoded_metar['wind_miles_per_hour'] / 1.609), 0.16));
}
return $decoded_metar;
}
?>