{"id":168,"date":"2010-01-14T12:17:22","date_gmt":"2010-01-14T12:17:22","guid":{"rendered":"http:\/\/blog.stratus.org.uk\/?page_id=168"},"modified":"2011-06-26T11:41:53","modified_gmt":"2011-06-26T10:41:53","slug":"php-weather-script-from-aprs-reports","status":"publish","type":"page","link":"https:\/\/blog.stratus.org.uk\/?page_id=168","title":{"rendered":"PHP: Weather script from APRS reports"},"content":{"rendered":"

Weather script from APRS reports
\n
\n global $image_format, $baseimg, $img;
\n$start_pressure = -1;
\n$end_pressure = -1;
\n\/\/
\n\/\/ handle any script inputs
\narray_shift($argv);
\nif ($argv[0] != null ){
\n$IMAGEFILE = $argv[0];
\n} else {
\n$IMAGEFILE = \"\/home\/stratuso\/cgi-bin\/wx_panel_white\/white600x70.jpg\";
\n}
\nif ($argv[1] != null ){
\n$OUTPUTIMAGEFILE = $argv[1];
\n} else {
\n$OUTPUTIMAGEFILE = \"\/home\/stratuso\/webroots\/ratair.stratus.org.uk\/wc\/wx.jpg\";
\n}
\n\/\/
\n$result = get_web_page( \"http:\/\/www.findu.com\/cgi-bin\/raw.cgi?call=m3nic&start=3&length=5&time=1\" );
\n\/\/
\nif ( $result == null ) {
\n\/* ... error: bad url, timeout, redirect loop ... *\/
\n}
\n\/\/
\nif ( $result['http_code'] != 200 ) {
\n\/* ... error: no page, no permissions, no service ... *\/
\n}
\n\/\/
\n$page = $result['content'];
\n\/\/
\n\/* Ok lets now parse ou tthe weather data *\/
\n\/\/
\n$output = strip_html_tags( $page );
\n\/\/
\n\/* Ok, now we need to strip out the stuff at the end *\/
\n\/\/
\n$pieces = explode( \"\\n\", $output);
\n\/\/
\nforeach($pieces as $left ){
\nif ( strlen($left) >5 ) {
\n$bit = strstr($left, \"@\");
\n$bit = ltrim($bit, \"@\");
\n$bit = trim($bit, \".Dvs\");
\n\/\/ by now we just have the following ...
\n\/\/ 1 2 3 4 5 6
\n\/\/ 01234567890123456789012345678901234567890123456789012345678901
\n\/\/ 112118z5210.97N\/00059.63E_229\/003g...t049r...p...P000h83b10216
\n$day = substr($bit,0, 2);
\n$time = substr($bit,2, 2).\":\".substr($bit,4,2);
\n$lat = substr($bit,7, 8);
\n$long = substr($bit,16, 9);
\n\/\/
\n$wind_dir = substr($bit,25, 4); \/\/ includes the _
\nif ( substr($wind_dir,0,1) == \"_\" ) {
\n$wind_dir = fnResolveWindDirection( substr($wind_dir,1,3) );
\n}else {
\n$wind_dir = \"***\";
\n}
\n\/\/
\n$wind_speed = substr($bit,29, 4);
\nif ( substr($wind_speed,0,1) == \"\/\" ) {
\n$wind_speed = fnProcessWindSpeed( substr($wind_speed,1,3) );
\n}else {
\n$wind_speed = \"***\";
\n}
\n\/\/
\n$wind_gust = substr($bit,33, 4);
\nif ( substr($wind_gust,0,1) == \"\/\" ) {
\n$wind_gust = fnProcessWindSpeed( substr($wind_gust,1,3) );
\n}else {
\n$wind_gust = \"***\";
\n}
\n\/\/
\n$temp_C = substr($bit,37, 4);
\nif ( substr($temp_C,0,1) == \"t\" ) {
\n$farenheight = substr($temp_C,1,3); \/\/ this is kept for later too
\n$temp_C = fnProcessCurrentTemperature( $farenheight );
\n}else {
\n$temp_C = \"***\";
\n}
\n\/\/
\n$rain = substr($bit,41, 4);
\nif ( substr($rain,0,1) == \"r\" ) {
\n$rain = fnProcessRainFall( substr($rain,1,3) );
\n}else {
\n$rain = \"***\";
\n}
\n\/\/
\n$rain_24 = substr($bit,45, 4);
\nif ( substr($rain_24,0,1) == \"p\" ) {
\n$rain_24 = fnProcessRainFall( substr($rain_24,1,3) );
\n}else {
\n$rain_24 = \"***\";
\n}
\n\/\/
\n$rain_since_mid = substr($bit,49, 4);
\nif ( substr($rain_since_mid,0,1) == \"P\" ) {
\n$rain_since_mid = fnProcessRainFall( substr($rain_since_mid,1,3) );
\n}else {
\n$rain_since_mid = \"***\";
\n}
\n\/\/
\n$humidity = substr($bit,53, 3);
\nif ( substr($humidity,0,1) == \"h\" ) {
\n$humidity = fnProcessHumidity( substr($humidity,1,2) );
\n}else {
\n$humidity = \"***\";
\n}
\n\/\/
\n$pressure = substr($bit,56, 6);
\nif ( substr($pressure,0,1) == \"b\" ) {
\n$pressure = fnProcessPressure( substr($pressure,1,5) );
\n}else {
\n$pressure = \"***\";
\n}
\n\/\/
\nif ($start_pressure == -1) # then first time
\n{
\n}
\n\/\/
\n$pressure = substr($bit,56, 6);
\nif ( substr($pressure,0,1) == \"b\" ) {
\n$pressure = fnProcessPressure( substr($pressure,1,5) );
\n}else {
\n$pressure = \"***\";
\n}
\n\/\/
\nif ($start_pressure == -1) # then first time
\n{
\n$start_pressure = $pressure;
\n} else {
\n$end_pressure = $pressure;
\n}
\n}
\n\/\/print ( \"\\n$bit\");
\n\/\/
\n}
\n\/\/ Summary here
\nif ( $start_pressure > $end_pressure ) {
\n$pressure = $pressure.\" (rise)\";
\n\/\/print (\"\\nPressure rising\");
\n} elseif ( $start_pressure < $end_pressure ) {
\n$pressure = $pressure.\" (fall)\";
\n\/\/print (\"\\nPressure falling\");
\n} else {
\n$pressure = $pressure.\" (steady)\";
\n\/\/print (\"\\nPressure steady\");
\n}<\/code><\/p>\n

$dewpoint_C = fnCalcDewPoint($farenheight, $humidity);
\n$cloud_base = fnCalcCloudBase($dewpoint_C, $temp_C);
\n\/\/
\n\/\/print ( \"\\n--------------------\");
\nprint ( \"\\n$day\");
\nprint ( \"\\n$time\");
\nprint ( \"\\n$lat\");
\nprint ( \"\\n$long\");
\nprint ( \"\\n$wind_dir\");
\nprint ( \"\\n$wind_speed\");
\nprint ( \"\\n$wind_gust\");
\nprint ( \"\\n$temp_C\");
\nprint ( \"\\n$rain\");
\nprint ( \"\\n$rain_24\");
\nprint ( \"\\n$rain_since_mid\");
\nprint ( \"\\n$humidity\");
\nprint ( \"\\n$dewpoint_C\");
\nprint ( \"\\n$pressure\");
\nprint ( \"\\n$cloud_base\");
\n\/\/
\nfnWriteImage( $day, $time, $lat, $long,
\n$wind_dir, $wind_speed, $wind_gust,
\n$temp_C, $humidity, $cloud_base, $dewpoint_C,
\n$pressure, $IMAGEFILE, $OUTPUTIMAGEFILE );
\n\/\/
\n\/\/ End of main body of the script ---------------------------------------
\n\/\/
\n\/************************************************************************
\n* Get a web file (HTML, XHTML, XML, image, etc.) from a URL. Return an
\n* array containing the header fields and content.
\n*\/
\nfunction get_web_page( $url )
\n{
\n$options = array( 'http' => array(
\n'user_agent' => 'spider', \/\/ who am i
\n'max_redirects' => 10, \/\/ stop after 10 redirects
\n'timeout' => 120, \/\/ timeout on response
\n) );
\n$context = stream_context_create( $options );
\n$page = @file_get_contents( $url, false, $context );
\n\/\/
\n$result = array( );
\nif ( $page != false )
\n$result['content'] = $page;
\nelse if ( !isset( $http_response_header ) )
\nreturn null; \/\/ Bad url, timeout
\n\/\/
\n\/\/ Save the header
\n$result['header'] = $http_response_header;
\n\/\/
\n\/\/ Get the *last* HTTP status code
\n$nLines = count( $http_response_header );
\nfor ( $i = $nLines-1; $i >= 0; $i-- )
\n{
\n$line = $http_response_header[$i];
\nif ( strncasecmp( \"HTTP\", $line, 4 ) == 0 )
\n{
\n$response = explode( ' ', $line );
\n$result['http_code'] = $response[1];
\nbreak;
\n}
\n}
\n\/\/
\nreturn $result;
\n}
\n\/* ********************************************************************** *\/
\n\/**
\n* Remove HTML tags, including invisible text such as style and
\n* script code, and embedded objects. Add line breaks around
\n* block-level tags to prevent word joining after tag removal.
\n*\/
\nfunction strip_html_tags( $text )
\n{
\n$text = preg_replace(
\narray(
\n\/\/ Remove invisible content
\n'@]*?>.*?@siu',
\n'@
\n<\/p>\n

@siu',
\n'@@siu',
\n'@]*?.*?@siu',
\n'@]*?.*?@siu',
\n'@]*?.*?@siu',
\n'@]*?.*?@siu',
\n'@@siu',
\n'@]*?.*?@siu',
\n\/\/ Add line breaks before and after blocks
\n'@ '@ '@ '@ '@ '@ '@ ),
\narray(
\n' ', ' ', ' ', ' ', ' ', ' ', ' ', ' ', ' ',
\n\"\\n\\$0\", \"\\n\\$0\", \"\\n\\$0\", \"\\n\\$0\", \"\\n\\$0\", \"\\n\\$0\",
\n\"\\n\\$0\", \"\\n\\$0\",
\n),
\n$text );
\nreturn strip_tags( $text );
\n}
\n\/\/ ########################################################################
\nfunction fnResolveWindDirection( $sWindDegrees )
\n{
\n$wind_dir = $sWindDegrees;
\n# Cardinal Direction Degree Direction
\n#N 348.75 - 11.25
\n#NNE 11.25 - 33.75
\n#NE 33.75 - 56.25
\n#ENE 56.25 - 78.75
\n#E 78.75 - 101.25
\n#ESE 101.25 - 123.75
\n#SE 123.75 - 146.25
\n#SSE 146.25 - 168.75
\n#S 168.75 - 191.25
\n#SSW 191.25 - 213.75
\n#SW 213.75 - 236.25
\n#WSW 236.25 - 258.75
\n#W 258.75 - 281.25
\n#WNW 281.25 - 303.75
\n#NW 303.75 - 326.25
\n#NNW 326.25 - 348.75
\n\/\/
\nif ( (($wind_dir >= 348) && ($wind_dir <= 359))||(($wind_dir >= 0) && ($wind_dir <= 11)) ) {
\n#N 348.75 - 11.25
\n$wind_ind = \"N\";
\n} elseif ( (($wind_dir >= 12) && ($wind_dir <= 33)) ) {
\n#NNE 11.25 - 33.75
\n$wind_ind = \"NNE\";
\n} elseif ( (($wind_dir >= 34) && ($wind_dir <= 56)) ) {
\n#NE 33.75 - 56.25
\n$wind_ind = \"NE\";
\n} elseif ( (($wind_dir >= 57) && ($wind_dir <= 78)) ) {
\n#ENE 56.25 - 78.75
\n$wind_ind = \"ENE\";
\n} elseif ( (($wind_dir >= 79) && ($wind_dir <= 101)) ) {
\n#E 78.75 - 101.25
\n$wind_ind = \"E\";
\n} elseif ( (($wind_dir >= 102) && ($wind_dir <= 146)) ) {
\n#SE 123.75 - 146.25
\n$wind_ind = \"SE\";
\n} elseif ( (($wind_dir >= 147) && ($wind_dir <= 168)) ) {
\n#SSE 146.25 - 168.75
\n$wind_ind = \"SSE\";
\n} elseif ( (($wind_dir >= 169) && ($wind_dir <= 191)) ) {
\n#S 168.75 - 191.25
\n$wind_ind = \"S\";
\n} elseif ( (($wind_dir >= 192) && ($wind_dir <= 213)) ) {
\n#SSW 191.25 - 213.75
\n$wind_ind = \"SSW\";
\n} elseif ( (($wind_dir >= 214) && ($wind_dir <= 258)) ) {
\n#WSW 236.25 - 258.75
\n$wind_ind = \"WSW\";
\n} elseif ( (($wind_dir >= 259) && ($wind_dir <= 281)) ) {
\n#W 258.75 - 281.25
\n$wind_ind = \"W\";
\n} elseif ( (($wind_dir >= 282) && ($wind_dir <= 303)) ) {
\n#WNW 281.25 - 303.75
\n$wind_ind = \"WNW\";
\n} elseif ( (($wind_dir >= 304) && ($wind_dir <= 326)) ) {
\n#NW 303.75 - 326.25
\n$wind_ind = \"NW\";
\n} elseif ( (($wind_dir >= 327) && ($wind_dir <= 347)) ) {
\n#NNW 326.25 - 348.75
\n$wind_ind = \"NNW\";
\n} else {
\n# do nothing
\n$wind_ind =\"\";
\n}
\n$wind_ind = $wind_ind.\" (\".$wind_dir.\")\";
\n\/\/
\nreturn $wind_ind;
\n}
\n\/\/ ########################################################################
\n\/\/ This turns it into Knots and sets the calm if zero
\nfunction fnProcessWindSpeed( $sWindspeed )
\n{
\nif ($sWindspeed == \"000\"){
\n$windspeed = \"Calm\";
\n\/\/print \"\\nWindspeed is zero - set to calm\";
\n} else {
\n$windspeed = sprintf(\"%d kt\",$sWindspeed*0.8689755962687);
\n}
\nreturn $windspeed;
\n}
\n\/\/ ########################################################################
\nfunction fnProcessCurrentTemperature( $sTemp )
\n{
\n$faren = sprintf(\"%.1f\", $sTemp);
\n$temp = sprintf(\"%.1f\", ((5\/9) *($faren - 32)));
\n$temp = $temp.\"C\";
\n\/\/print \"\\ntemp modified to \".$temp;<\/p>\n

return $temp;
\n}
\n\/\/ ########################################################################
\nfunction fnProcessRainFall( $sRain )
\n{
\n$rain = sprintf(\"%3d\", ($sRain*(25\/100))). \" mm\";<\/p>\n

return $rain;
\n}
\n\/\/ ########################################################################
\nfunction fnProcessHumidity( $sHumidity )
\n{
\nif ($sHumidity == \"00\"){
\n$humidity = \"100%\";
\n\/\/print \"\\nHumidity modified to 100\";
\n} else
\n$humidity = sprintf(\"%s\", $sHumidity). \"%\";
\n\/\/print \"\\nHumidity='\".$humidity.\"'\";<\/p>\n

return $humidity;
\n}
\n\/\/ ########################################################################
\nfunction fnProcessPressure( $sPressure )
\n{
\n$press = $sPressure \/ 10;
\n$press = $press.\" mb\";
\n\/\/print \"\\nModified pressure = $press[0]\";<\/p>\n

return $press;
\n}
\n\/\/ ########################################################################
\nfunction fnWriteImage( $day, $time, $lat, $long, $wind_dir, $wind_speed,
\n$wind_gust, $temp, $humidity, $cloud_base, $dew_point, $pressure, $sInputFileName, $sOutputFileName )
\n{<\/p>\n

<\/code><\/p>\n

\/\/ create the base image
\nglobal $image_format, $baseimg, $img;
\n\/\/
\n$image_format = 'jpeg';
\n\/\/
\n\/\/ create a truecolor image to deal avoid any pallete problems
\nprint \"\\nReading $sInputFileName\";
\nprint \"\\nWriting $sOutputFileName\";
\n$baseimg = imagecreatefromjpeg($sInputFileName);
\n$basex = imagesx($baseimg);
\n$basey = imagesy($baseimg);
\nprint \"\\nSize is $basex by $basey\\n\";
\n\/\/
\n$img = imagecreatetruecolor($basex,$basey);
\nimagecopy($img,$baseimg,0,0,0,0,$basex,$basey);
\n\/\/
\n$color1 = imagecolorallocate($img,255,0,0); \/\/ RED
\n$color2 = imagecolorallocate($img,0,128,0); \/\/ GREEN
\n$color3 = imagecolorallocate($img,0,0,255); \/\/ BLUE
\n$BLACK = imagecolorallocate($img,0,0,0); \/\/ BLACK
\n$WHITE = imagecolorallocate($img,255,255,255); \/\/ WHITE
\n$color6 = imagecolorallocate($img,255,215,0); \/\/ GOLD
\n$color7 = imagecolorallocate($img,135,206,235); \/\/ sky blue
\n$ROYAL_BLUE = imagecolorallocate($img,065,105,225); \/\/
\n\/\/
\n$root_x = 9;
\n$root_y = 1;
\n\/\/
\n# now put the text on top of the box
\nimagestring($img, 2, $root_x, $root_y, \"Weather Report at $time ($day)\", $ROYAL_BLUE);
\nimagestring($img, 2, $root_x + 10, $root_y + 12, \"Temperature: $temp\", $ROYAL_BLUE);
\nimagestring($img, 2, $root_x + 10, $root_y + 24, \"Cloud Base : $cloud_base\", $ROYAL_BLUE);
\nimagestring($img, 2, $root_x + 200, $root_y + 12, \"Dew Point: $dew_point\", $ROYAL_BLUE);
\nimagestring($img, 2, $root_x + 200, $root_y + 24, \"Relative Humidity: $humidity\", $ROYAL_BLUE);
\nimagestring($img, 2, $root_x + 10, $root_y + 36, \"Local QFE: $pressure\", $ROYAL_BLUE);
\nimagestring($img, 2, $root_x + 200, $root_y + 36, \"Wind: $wind_speed $wind_dir (gust $wind_gust)\", $ROYAL_BLUE);
\n\/\/
\n\/\/ ok now write the file
\nimagejpeg($img, \"$sOutputFileName\");
\n\/\/
\n\/\/ get rid of the image since we don't need it in memory any more.
\n\/\/ don't need any memory leaks taking down the server
\nimagedestroy($img);
\nimagedestroy($baseimg);
\n} \/\/ end function imagecenteredtext
\n\/\/ ########################################################################
\nfunction fnCalcDewPoint($faren, $humidity )
\n{
\n# lets calc the dew point
\n$dew_point_F = $faren -((100 - $humidity)\/5); # in farenheight
\n$dew_point_C = sprintf(\"%.1fC\",($dew_point_F - 32) * (5\/9));
\n\/\/
\nreturn $dew_point_C;
\n}
\n\/\/ ########################################################################
\nfunction fnCalcCloudBase($dew_point_C, $temp_C )
\n{
\n\/\/
\n#estimate the cloud base
\n$est_cb = ($temp_C - $dew_point_C) * 1000;
\n\/\/
\nif ( $est_cb < 600) {
\n$est_cloud_base = \"<600ft\";
\n} else {
\n$est_cloud_base = sprintf(\"%dft\",$est_cb);
\n}
\n\/\/
\n\/\/print \"\\nTemp C = $temp_C\";
\n\/\/print \"\\nDew Point C = $dew_point_C\";
\n\/\/print \"\\nCloud Base = $est_cloud_base\";
\n\/\/
\nreturn $est_cloud_base;
\n}
\n\/\/ ########################################################################
\n?>
\n<\/code><\/p>\n","protected":false},"excerpt":{"rendered":"

Weather script from APRS reports global $image_format, $baseimg, $img; $start_pressure = -1; $end_pressure = -1; \/\/ \/\/ handle any script inputs array_shift($argv); if ($argv[0] != null ){ $IMAGEFILE = $argv[0]; } else { $IMAGEFILE = “\/home\/stratuso\/cgi-bin\/wx_panel_white\/white600x70.jpg”; } if ($argv[1] != … Continue reading →<\/span><\/a><\/p>\n","protected":false},"author":1,"featured_media":0,"parent":84,"menu_order":0,"comment_status":"closed","ping_status":"open","template":"","meta":{"footnotes":""},"class_list":["post-168","page","type-page","status-publish","hentry"],"_links":{"self":[{"href":"https:\/\/blog.stratus.org.uk\/index.php?rest_route=\/wp\/v2\/pages\/168","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/blog.stratus.org.uk\/index.php?rest_route=\/wp\/v2\/pages"}],"about":[{"href":"https:\/\/blog.stratus.org.uk\/index.php?rest_route=\/wp\/v2\/types\/page"}],"author":[{"embeddable":true,"href":"https:\/\/blog.stratus.org.uk\/index.php?rest_route=\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/blog.stratus.org.uk\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=168"}],"version-history":[{"count":24,"href":"https:\/\/blog.stratus.org.uk\/index.php?rest_route=\/wp\/v2\/pages\/168\/revisions"}],"predecessor-version":[{"id":425,"href":"https:\/\/blog.stratus.org.uk\/index.php?rest_route=\/wp\/v2\/pages\/168\/revisions\/425"}],"up":[{"embeddable":true,"href":"https:\/\/blog.stratus.org.uk\/index.php?rest_route=\/wp\/v2\/pages\/84"}],"wp:attachment":[{"href":"https:\/\/blog.stratus.org.uk\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=168"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}