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  • Jquery loads only after F5 in IE

    - by khushi
    I am using Jcrop jQuery to crop image in MVC3 application. following is my javacript function: jQuery(function ($) { $('#imgLab').Jcrop( { onChange: showCoords, onSelect: coordsSelected, onRelease: clearCoords } ); }); Image ID is 'imgLab'. Image src path is coming from database. Now this work fine in FF,Safari and Chrome. but in IE it only works after I press F5. Can anyone tell me what is wrong in code? Thanks in Advance. Khushbu

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  • Give a number to return the approximated value of an Enum?

    - by ElektroStudios
    I have this enumeration: Enum Lame_Bitrate kbps_8 = 8 kbps_16 = 16 kbps_24 = 24 kbps_32 = 32 kbps_40 = 40 kbps_48 = 48 kbps_56 = 56 kbps_64 = 64 kbps_80 = 80 kbps_96 = 96 kbps_112 = 112 kbps_128 = 128 kbps_144 = 144 kbps_160 = 160 kbps_192 = 192 kbps_224 = 224 kbps_256 = 256 kbps_320 = 320 End Enum And I would like to return the approximated value of the Enum given a number. For example, if I have the number 190 then I expect to find the more approximated value in the Enum to return the 192 (kbps_192 value of the Enum), if I have the number 196 then again I expect to return the value 192 (not return the next value 224 because is less approximated). Something like this: Private Sub Test() Dim wma_file As String = "C:\windows media audio file.wma" Dim wma_file_Bitrate As Integer = 172 Dim mp3_bitrate_approximated As Integer mp3_bitrate_approximated = Return_Approximated_Value_Of_Enum(wma_file_Bitrate) End Sub private function Return_Approximated_Value_Of_Enum(byval value as integer) as integer return... enum.find(value).approximated... end function Exist any framework method to find the more approximated number given other number in a Enum? I hope you can understand my question, thank you. PS: I prefer a solution using LINQ extensions if can be.

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  • array won't work actionscript 3

    - by steve
    I've tried everything. Arrays are quite simple so I don't know why this doesn't function: var menuList:Array = [menu_bag_mc,menu_chips_mc,menu_coke_mc,menu_cup_mc,menu_deodorant_mc,menu_fork_mc,menu_knife_mc,menu_lighter_mc,menu_milk_mc,menu_pill_mc,menu_rings_mc,menu_shampoo_mc,menu_spoon_mc,menu_straw_mc,menu_toothbrush_mc,menu_trashbag_mc,menu_water_mc]; function captureAllClicks(event:MouseEvent):void { trace(menuList.indexOf(event.target)); } stage.addEventListener(MouseEvent.CLICK, captureAllClicks); Every time I click on any of the items on the stage (which are all given the instance names listed above. each is a tweening movieclip containing a button) I get a trace of -1. WHY?!

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  • Change the colors of JvectorMap when there are 2 maps on the page

    - by Youssef
    i am using Jvectormap to place 2 maps on my page. the maps are placed normally and everything is fine. they are placed in 2 different divs: <div id="map1"> </div> <div id="map2"> </div> and the Jquery: $(function () { $('#map1').vectorMap({ color: '#aaaaaa', backgroundColor: '#ffffff', hoverOpacity: 1, hoverColor: true }); }); $(function () { $('#map2').vectorMap({ color: '#aaaaaa', backgroundColor: '#ffffff', hoverOpacity: 1, }); }); Now when I try to change the colors of map2 dynamically using: $("#map2").vectorMap("set", "colors", colorsDictionnary); The colors of the first one only is changed. and this happens only when changing colors. Always the first one have it's colors changed even if I am using $("#map2") How can change the colors of the map2 without touching map1? Thank you very much for any help, I really need it

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  • how do i change the value of an input field with jquery?

    - by Lina
    Hi, i'm trying to use jquery to change the value of an input text box, but it's not working, here is my code... <form method="get"> <input id="temp" type="text" name="here" value="temp value" /> <input class="form" type="radio" value="1" name="someForm" /> Enter something Here: <input id="input" type="text" name="here" value="test value" /> </form> <script> var cachedAjax = new Object(); $(document).ready(function () { $('.form').click(function () { var newvalue = $("#input").val(); $("#temp").val(newvalue); $("input").val($(temp).val()); }); }); </script> the value of the "#input" text box is not changing!!!!!! why is that??? what am i missing??? thanks a 10 million in advance

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  • Slider with keypress control bugs when keys pressed to quickly.

    - by Jaybuz
    Hello, I've made a slider that uses the left and right arrow keys to move the slide but when pressed to quickly it will bug a little and I was wondering if it's possible to limit the amount of presses in say a second. You can see it here: {link} $('#slider-nav div').click(function() { $('#slider-nav div').removeClass('selected').addClass(''); $('#slider-nav div:eq('+($.jcarousel.intval($(this).text())-1)+')').addClass('selected'); }) // Allow left and right keys to control slider $(document.documentElement).keypress(function(e) { var code = (e.keyCode ? e.keyCode : e.which); var direction = null; // handle cursor keys if (code == 37) { // left key direction = 'prev'; } else if (code == 39) { // right key direction = 'next'; } if (direction != null) { $('#slider-nav div.selected')[direction]().click(); } });

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  • Help with IF THEN breaking when comparing results from MYSQL query.

    - by roydukkey
    I'm have a problem with an invite system. The if statement seems to break. It shows the message "Fail" but the UPDATE statement still executes. Why do both the THEN and the ELSE excute? $dbConn = new dbConn(); // Check if POST user_username and user_hash are matching and valid; both are hidden for fields $sql = "SELECT user_username " . "FROM table_users " . "WHERE user_id=".mysql_real_escape_string($_POST["user_id"])." " . "AND user_hash='".mysql_real_escape_string($_POST["user_hash"])."' " . "AND user_enabled=0;"; $objUser = $dbConn->query($sql); // If result contains 1 or more rows if( mysql_num_rows($objUser) != NULL ){ $objUser = mysql_fetch_assoc($objUser); $ssnUser->login( $objUser["user_username"] ); $sql = "UPDATE table_users SET " . "user_enabled=1, " . "user_first_name='".mysql_real_escape_string($_POST["user_first_name"])."', " . "user_last_name='".mysql_real_escape_string($_POST["user_last_name"])."', " . "user_password='".mysql_real_escape_string( md5($_POST["user_password"]) )."' " . "WHERE user_id=".mysql_real_escape_string($_POST["user_id"]).";"; $dbConn->query($sql); echo "Success"; header( "Refresh: 5; url=/account/?action=domains" ); } else { echo "Fail"; } This dbConn Class is as follows: class dbConn{ var $username = "xxxx_admin"; var $password = "xxxxxxxx"; var $server = "localhost"; var $database = "xxxx"; var $objConn; function __construct(){ $conn = mysql_connect( $this->server, $this->username, $this->password, true ); if( !$conn ){ die("Could not connect: ".mysql_error() ); } else { $this->objConn = $conn; } unset($conn); } function __destruct(){ mysql_close( $this->objConn ); unset( $this ); } function query( $query, $db = false ){ mysql_select_db( $db != false ? $db : $this->database, $this->objConn ); $result = mysql_query( $query ); unset($query,$db); return $result; } }

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  • please help me to find out where i am doing mistake in this code? i wnat retieve the value that i am

    - by user309381
    function reload(form) { var val = $('seltab').getValue(); new Ajax.Request('Website.php?cat=' +escape(val), { method:'get', onSuccess: function(transport){ var response = transport.responseText ; $("MyDivDB").innerHTML = transport.responseText ; alert("Success! \n\n" + response); }, onFailure: function(){ alert('Something went wrong...') } }); } </script> </head> title author pages $con = mysql_connect($dbhostname,$dbuserid,$dbpassword); if(!$con) { die ("connection failed".mysql_error()); } $db = mysql_select_db($dbname,$con); if(!$db) { die("Database is not selected".mysql_error()); } $query ="SELECT * FROM books NATURAL JOIN authors" ; $result = mysql_query($query); if(!$query) { die("Database is not query".mysql_error()); } while($row = mysql_fetch_array($result,MYSQL_ASSOC)) { $title = $row["title"]; $author = $row["author"]; $page = $row["pages"]; echo "<tr>"; echo "<td>$title</td>"; echo "<td>$author</td>"; echo "<td>$page</td>"; echo "</tr>"; } print "</table>"; echo "<select id = seltab onchange = 'reload(this.form)'>"; $querysel = "SELECT title_id,author FROM authors NATURAL JOIN books"; $result1 = mysql_query($querysel) ; while($rowID = mysql_fetch_assoc($result1)) { $TitleID = $rowID['title_id']; $author = $rowID['author']; print "<option value = $author>$author\n"; print "</option>"; } print "</select>"; ? Wbsite.php

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  • Using JSON Data to Populate a Google Map with Database Objects

    - by MikeH
    I'm revising this question after reading the resources mentioned in the original answers and working through implementing it. I'm using the google maps api to integrate a map into my Rails site. I have a markets model with the following columns: ID, name, address, lat, lng. On my markets/index view, I want to populate a map with all the markets in my markets table. I'm trying to output @markets as json data, and that's where I'm running into problems. I have the basic map displaying, but right now it's just a blank map. I'm following the tutorials very closely, but I can't get the markers to generate dynamically from the json. Any help is much appreciated! Here's my setup: Markets Controller: def index @markets = Market.filter_city(params[:filter]) respond_to do |format| format.html # index.html.erb format.json { render :json => @market} format.xml { render :xml => @market } end end Markets/index view: <head> <script type="text/javascript" src="http://www.google.com/jsapi?key=GOOGLE KEY REDACTED, BUT IT'S THERE" > </script> <script type="text/javascript"> var markets = <%= @markets.to_json %>; </script> <script type="text/javascript" charset="utf-8"> google.load("maps", "2.x"); google.load("jquery", "1.3.2"); </script> </head> <body> <div id="map" style="width:400px; height:300px;"></div> </body> Public/javascripts/application.js: function initialize() { if (GBrowserIsCompatible() && typeof markets != 'undefined') { var map = new GMap2(document.getElementById("map")); map.setCenter(new GLatLng(40.7371, -73.9903), 13); map.addControl(new GLargeMapControl()); function createMarker(latlng, market) { var marker = new GMarker(latlng); var html="<strong>"+market.name+"</strong><br />"+market.address; GEvent.addListener(marker,"click", function() { map.openInfoWindowHtml(latlng, html); }); return marker; } var bounds = new GLatLngBounds; for (var i = 0; i < markets.length; i++) { var latlng=new GLatLng(markets[i].lat,markets[i].lng) bounds.extend(latlng); map.addOverlay(createMarker(latlng, markets[i])); } } } window.onload=initialize; window.onunload=GUnload;

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  • Pointer to local variable

    - by Radek Šimko
    May I have any acces to local variable in different function? If may, how? void replaceNumberAndPrint(int array[3]) { printf("%i\n", array[1]); printf("%i\n", array[1]); } int * getArray() { int myArray[3] = {4, 65, 23}; return myArray; } int main() { replaceNumberAndPrint(getArray()); } The output of the piece of code above: 65 4202656 What am i doing wrong? What the "4202656" means?? Do I have to copy the whole array in the replaceNumberAndPrint() function to be able to access to it more than first times?

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  • What is the proper way to declare a specialization of a template for another template type?

    - by Head Geek
    The usual definition for a specialization of a template function is something like this: class Foo { [...] }; namespace std { template<> void swap(Foo& left, Foo& right) { [...] } } // namespace std But how do you properly define the specialization when the type it's specialized on is itself a template? Here's what I've got: template <size_t Bits> class fixed { [...] }; namespace std { template<size_t Bits> void swap(fixed<Bits>& left, fixed<Bits>& right) { [...] } } // namespace std Is this the right way to declare swap? It's supposed to be a specialization of the template function std::swap, but I can't tell whether the compiler is seeing it as such, or whether it thinks that it's an overload of it or something.

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  • tablednd post issue help please

    - by netrise
    Hi plz i got a terrible headache my script is very simple Why i can’t get $_POST['table-2'] after submiting update button, i want to get ID numbers sorted # index.php <head> <script src="jquery.js" type="text/javascript"></script><br /> <script src="jquery.tablednd.js" type="text/javascript"></script><br /> <script src="jqueryTableDnDArticle.js" type="text/javascript"></script><br /> </head> <body> <form method='POST' action=index.php> <table id="table-2" cellspacing="0" cellpadding="2"> <tr id="a"><td>1</td><td>One</td><td><input type="text" name="one" value="one"/></td></tr> <tr id="b"><td>2</td><td>Two</td><td><input type="text" name="two" value="two"/></td></tr> <tr id="c"><td>3</td><td>Three</td><td><input type="text" name="three" value="three"/></td></tr> <tr id="d"><td>4</td><td>Four</td><td><input type="text" name="four" value="four"/></td></tr> <tr id="e"><td>5</td><td>Five</td><td><input type="text" name="five" value="five"/></td></tr> </table> <input type="submit" name="update" value="Update"> </form> <?php $result[] = $_POST['table-2']; foreach($result as $value) { echo "$value<br/>"; } ?> </body> # jqueryTableDnDArticle.js …………. $(“#table-2?).tableDnD({ onDragClass: “myDragClass”, onDrop: function(table, row) { var rows = table.tBodies[0].rows; var debugStr = “Row dropped was “+row.id+”. New order: “; for (var i=0; i<rows.length; i++) { debugStr += rows[i].id+" "; } //$("#debugArea").html(debugStr); $.ajax({ type: "POST", url: "index.php", data: $.tableDnD.serialize(), success: function(html){ alert("Success"); } }); }, onDragStart: function(table, row) { $("#debugArea").html("Started dragging row "+row.id); } });

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  • Getting value from key pair value into appended property using jQuery

    - by Neil
    How do I get the value from a key pair value into the rel property of an anchor tag? When I split the code to put the value in the correct place it doesn't work, the end of the a tag would appear on screen instead value wouldn't be applied. When I look at the resulting code in console in Firebug the rel and href swapped order so the rel is first. The 'key' should be and is in the correct location but the 'value' needs to be applied to the rel attribute. What am I doing wrong? $(function() { var obj = {"firstThing":"4","secondThing":"6","aThirdThing":"2","anotherThing":"3","followedByAnother":"4"}; $.each(obj, function(key,value) { $('#newmine').append("<li class='tagBlocks'>","<a href='#' rel=''>",value," ",key); }); });

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  • Wordpress pages address rewrite

    - by kemp
    UPDATE I tried using the internal wordpress rewrite. What I have to do is an address like this: http://example.com/galleria/artist-name sent to the gallery.php page with a variable containing the artist-name. I used these rules as per Wordpress' documentation: // REWRITE RULES (per gallery) {{{ add_filter('rewrite_rules_array','wp_insertMyRewriteRules'); add_filter('query_vars','wp_insertMyRewriteQueryVars'); add_filter('init','flushRules'); // Remember to flush_rules() when adding rules function flushRules(){ global $wp_rewrite; $wp_rewrite->flush_rules(); } // Adding a new rule function wp_insertMyRewriteRules($rules) { $newrules = array(); $newrules['(galleria)/(.*)$'] = 'index.php?pagename=gallery&galleryname=$matches[2]'; return $newrules + $rules; } // Adding the id var so that WP recognizes it function wp_insertMyRewriteQueryVars($vars) { array_push($vars, 'galleryname'); return $vars; } what's weird now is that on my local wordpress test install, that works fine: the gallery page is called and the galleryname variable is passed. On the real site, on the other hand, the initial URL is accepted (as in it doesn't go into a 404) BUT it changes to http://example.com/gallery (I mean it actually changes in the browser's address bar) and the variable is not defined in gallery.php. Any idea what could possibly cause this different behavior? Alternatively, any other way I couldn't think of which could achieve the same effect described in the first three lines is perfectly fine. Old question What I need to do is rewriting this address: (1) http://localhost/wordpress/fake/text-value to (2) http://localhost/wordpress/gallery?somevar=text-value Notes: the remapping must be transparent: the user always has to see address (1) gallery is a permalink to a wordpress page, not a real address I basically need to rewrite the address first (to modify it) and then feed it back to mod rewrite again (to let wordpress parse it its own way). Problems if I simply do RewriteRule ^fake$ http://localhost/wordpress/gallery [L] it works but the address in the browser changes, which is no good, if I do RewriteRule ^fake$ /wordpress/gallery [L] I get a 404. I tried different flags instead of [L] but to no avail. How can I get this to work? EDIT: full .htaccess # BEGIN WordPress <IfModule mod_rewrite.c> RewriteEngine On RewriteRule ^fake$ /wordpress/gallery [R] RewriteBase /wordpress/ RewriteCond %{REQUEST_FILENAME} !-f RewriteCond %{REQUEST_FILENAME} !-d RewriteRule . /wordpress/index.php [L] </IfModule> # END WordPress

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  • Haskell: variant of `show` that doesn't wrap String and Char in quotes

    - by Joey Adams
    I'd like a variant of show (let's call it label) that acts just like show, except that it doesn't wrap Strings in " " or Chars in ' '. Examples: > label 5 "5" > label "hello" "hello" > label 'c' "c" I tried implementing this manually, but I ran into some walls. Here is what I tried: {-# LANGUAGE FlexibleInstances #-} {-# LANGUAGE UndecidableInstances #-} module Label where class (Show a) => Label a where label :: a -> String instance Label [Char] where label str = str instance Label Char where label c = [c] -- Default case instance Show a => Label a where label x = show x However, because the default case's class overlaps instance Label [Char] and instance Label Char, those types don't work with the label function. Is there a library function that provides this functionality? If not, is there a workaround to get the above code to work?

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  • Validate zip and display error with onBlur event

    - by phil
    Check if zip is 5 digit number, if not then display 'zip is invalid'. I want to use onBlur event to trigger the display. But it's not working. <script> $(function(){ function valid_zip() { var pat=/^[0-9]{5}$/; if ( !pat.test( $('#zip').val() ) ) {$('#zip').after('<p>zip is invalid</p>');} } }) </script> zip (US only) <input type="text" name='zip' id='zip' maxlength="5" onBlur="valid_zip()">

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  • Use LINQ to count the number of combinations existing in two lists

    - by Ben McCormack
    I'm trying to create a LINQ query (or queries) that count the total number of occurences of a combinations of items in one list that exist in a different list. For example, take the following lists: CartItems DiscountItems ========= ============= AAA AAA AAA BBB AAA BBB BBB CCC CCC DDD The result of the query operation should be 2 since I can find two combinations of AAA and BBB (from DiscountItems) within the contents of CartItems. My thinking in approaching the query is to join the lists together to shorten CartItems to only include items from DiscountItems. The solution would be to find the CartItem in the resulting query that occurs the least amount of times, thus indicating how many combinations of items exist in CartItems. How can this be done? Here's the query I already have, but it's not working. query results in an enumeration with 100 items, far more than I expected. Dim query = From cartItem In Cart.CartItems Group Join discountItem In DiscountGroup.DiscountItems On cartItem.SKU Equals discountItem.SKU Into Group Select SKU = cartItem.SKU, CartItems = Group Return query.Min(Function(x) x.CartItems.Sum(Function(y) y.Quantity))

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  • Avoid multiple autocomplete calls by wrapping it with SetTimeOut

    - by pixelboy
    Here's my issue : using an autocomplete jQuery plugin, I'd like to avoid multiple ajax requests when user strikes his keynoard by surrounding the $('#query1').autocomplete({ serviceUrl:'/actions/autocomplete?population=salon', minChars:3, maxHeight:300, width:200, clearCache:true, onSelect: function(suggestions,data){ $(".btn1").attr("href", "${pageContext.request.contextPath}/actions/espaceClients?participantId=" + data) } }); with something like var search = false; $('#query1, #query2, #query3').keyup(function(){ if (!search){ search = true; } if (search) { search = false; autocompleteThem(); } }); A you can see, above code is stupid, but it kinda shows what i'm trying to do. In simple words, if user dosen't type anything else in a certain period of time, then you can call autocomplete. I hope i'm being clear, as my brains are a mess...

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  • How can I handle multiple views of a data object? Which design pattern is acceptable?

    - by tranquil.byte
    I have a person object. class Person { private $name; ... } I need to be able to change how they are displayed on the front-end ( visitors have control ). They can choose list view, grid view, photo view for example. class PersonDisplay { public function displayList() { // Query database // Output html to display in list mode } public function displayPhoto() { // Query database // Output html to display in photo mode } } Is this an acceptable way to handle the presentation of the items on the front-end or is there a specific design pattern I should be researching to help me with this task? Does anyone have any suggestions or ideas where this could go wrong or if this could potentially make maintenance a nightmare? The Person object was just an example very similiar to what I am using.

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  • How to work with PHP abstract?

    - by YumYumYum
    Why would you use such abstract? Does it speed up work or what exactly its for? // file1.php abstract class Search_Adapter_Abstract { private $ch = null; abstract private function __construct() { } abstract public funciton __destruct() { curl_close($this->ch); } abstract public function search($searchString,$offset,$count); } // file2.php include("file1.php"); class abc extends Search_Adapter_Abstract { // Will the curl_close now automatically be closed? } What is the reason of extending abstract here? Makes me confused. What can i get from it now?

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  • newbie problems with codeigniter

    - by Patrick
    hi, i'm trying to learn codeigniter (following a book) but don't understand why the web page comes out empty. my controller is class Welcome extends Controller { function Welcome() { parent::Controller(); } function index() { $data['title'] = "Welcome to Claudia's Kids"; $data['navlist'] = $this->MCats->getCategoriesNav(); $data['mainf'] = $this->MProducts->getMainFeature(); $skip = $data['mainf']['id']; $data['sidef'] = $this->MProducts->getRandomProducts(3, $skip); $data['main'] = "home"; $this->load->vars($data); $this->load->view('template'); } the view is: <--doctype declaration etc etc.. --> </head> <body> <div id="wrapper"> <div id="header"> <?php $this->load->view('header');?> </div> <div id='nav'> <?php $this->load->view('navigation');?> </div> <div id="main"> <?php $this->load->view($main);?> </div> <div id="footer"> <?php $this->load->view('footer');?> </div> </div> </body> </html> Now I know the model is passing back the right variables, but the page appears completely blank. I would expect at least to see an error, or the basic html structure, but the page is just empty. Moreover, the controller doesn't work even if I modify it as follows: function index() { echo "hello."; } What am I doing wrong? Everything was working until I made some changes to the model - but even if I delete all those new changes, the page is still blank.. i'm really confused! thanks, P.

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  • BizTalk 2009 XSLT and Attribute Value Templates

    - by amok
    I'm trying to make use of attribute value type in a BizTalk XSL transformation to dynamically setting attribute or other element names. Read more here: http://www.w3.org/TR/xslt#dt-attribute-value-template The following code is an example of an XSL template to add an attribute optionally. <xsl:template name="AttributeOptional"> <xsl:param name="value"/> <xsl:param name="attr"/> <xsl:if test="$value != ''"> <xsl:attribute name="{$attr}"> <xsl:value-of select="$value"/> </xsl:attribute> </xsl:if> </xsl:template> Running this script in BizTalk results in "Exception from HRESULT: 0x80070002)" An alternative I was thinking of was to call a msxsl:script function to do the same but i cannot get a handle on the XSL output context from within the function. An ideas?

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  • Cloning a selector + all its children in jQuery?

    - by HipHop-opatamus
    I'm having trouble getting the following JQuery script to function properly - its functionality is as follows: 1) Hide the content below each headline 2) Upon clicking a headline, substitute the "#first-post" with the headline + the hidden content below the headline. I can only seem to get the script to clone the headline itself to #first-post, not the headline + the content beneath it. Any idea why? <HTML> <HEAD> <script src="http://code.jquery.com/jquery-latest.js"></script> </HEAD> <script> $(document).ready( function(){ $('.title').siblings().hide(); $('.title').click( function() { $('#first-post').replaceWith($(this).closest(".comment").clone().attr('id','first-post')); $('html, body').animate({scrollTop:0}, 'fast'); return false; }); }); </script> <BODY> <div id="first-post"> <div class="content"><p>This is a test discussion topic</p> </div> </div> <div class="comment"> <h2 class="title"><a href="#1">1st Post</a></h2> <div class="content"> <p>this is 1st reply to the original post</p> </div> <div class="test">1st post second line</div> </div> <div class="comment"> <h2 class="title"><a href="#2">2nd Post</a></h2> <div class="content"> <p>this is 2nd reply to the original post</p> </div> <div class="test">2nd post second line</div> </div> </div> <div class="comment"> <h2 class="title"><a href="#3">3rd Post</a></h2> <div class="content"> <p>this is 3rd reply to the original post</p> </div> <div class="test">3rd post second line</div> </div> </div> </BODY> </HTML>

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  • approximating log10[x^k0 + k1]

    - by Yale Zhang
    Greetings. I'm trying to approximate the function Log10[x^k0 + k1], where .21 < k0 < 21, 0 < k1 < ~2000, and x is integer < 2^14. k0 & k1 are constant. For practical purposes, you can assume k0 = 2.12, k1 = 2660. The desired accuracy is 5*10^-4 relative error. This function is virtually identical to Log[x], except near 0, where it differs a lot. I already have came up with a SIMD implementation that is ~1.15x faster than a simple lookup table, but would like to improve it if possible, which I think is very hard due to lack of efficient instructions. My SIMD implementation uses 16bit fixed point arithmetic to evaluate a 3rd degree polynomial (I use least squares fit). The polynomial uses different coefficients for different input ranges. There are 8 ranges, and range i spans (64)2^i to (64)2^(i + 1). The rational behind this is the derivatives of Log[x] drop rapidly with x, meaning a polynomial will fit it more accurately since polynomials are an exact fit for functions that have a derivative of 0 beyond a certain order. SIMD table lookups are done very efficiently with a single _mm_shuffle_epi8(). I use SSE's float to int conversion to get the exponent and significand used for the fixed point approximation. I also software pipelined the loop to get ~1.25x speedup, so further code optimizations are probably unlikely. What I'm asking is if there's a more efficient approximation at a higher level? For example: Can this function be decomposed into functions with a limited domain like log2((2^x) * significand) = x + log2(significand) hence eliminating the need to deal with different ranges (table lookups). The main problem I think is adding the k1 term kills all those nice log properties that we know and love, making it not possible. Or is it? Iterative method? don't think so because the Newton method for log[x] is already a complicated expression Exploiting locality of neighboring pixels? - if the range of the 8 inputs fall in the same approximation range, then I can look up a single coefficient, instead of looking up separate coefficients for each element. Thus, I can use this as a fast common case, and use a slower, general code path when it isn't. But for my data, the range needs to be ~2000 before this property hold 70% of the time, which doesn't seem to make this method competitive. Please, give me some opinion, especially if you're an applied mathematician, even if you say it can't be done. Thanks.

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