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  • From a 3D modeler to an iPhone app - what are best practices?

    - by bonkey
    I am quite new in 3D programming on iPhone and I would like to ask for hints about organizing a work between designers and programmers on that platform. Most of all: what kind of tools, libraries or plugins cooperate the best on both sides. Although I consider the question as looking for general best-practices advice I would like to find a solution for my current situation which I describe further, too. I've already done some research and found following libraries: SIO2 Khronos OpenGL ES 1.x SDK for PowerVR MBX Unity3D Oolong Game Engine I've checked modellers or plugins to them giving output formats readable by those tools: obj2opengl Wavefront OBJ to plain header file converter Blender with SIO2 exporter iphonewavefrontloader Cheetah3D PVRGeoPOD for 3DS / Maya Unfortunately I still have no clear vision how to combine any of that tools to get a desinger's work in an application. I look for a way of getting it in the most possible complete way: models, lights, scenes, textures, maybe some simple animations (but rather no game-like physics), but I still got nothing. And here comes my situation: I would like to find right way to present few (but quite complicated) models from a single scene. The designers mostly use 3DS Max 9, sometimes 10 (which partly prevents using PVRGeoPOD) and are rather reluctant to switch to something else but if there's no other choice I suppose it would be possible. The basic rule I've already found in some places "use Wavefront OBJ" not always works. I haven't got any acceptable results with production files, actually. The only things worked fine were some mere examples. Some of my models did imported incomplete, sometimes exporters hung or generated enormous files not really useful on an iPhone, sometimes enabling textures (with GL_TEXTURE_2D) just crashed an app. I know it might be a problem with too complicated models or my mistakes coming from inexeperience but I am not able to find any guidelines for that process to have streamlined cooperation with designers. I am even willing to write some things from scratch in pure OpenGL-ES if it's necessary, but I would like to avoid what might be avoided and get the most from the model files. The best would be the effect I saw on some SIO2 tutorials: export, build & go. But at that moment I've got only "import, wrong", "import, where are textures?", "import, that almost looks fine, export, hang" and so on... Is it really so much frustrating or I am just missed something obvious? Can anybody share his/her experience in that field and tell what kind of software uses for "making things happen"?

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  • Tearing my hair out - ASP.Net AJAX AutoComplete not working

    - by Dave
    Hope someone can help with this. I've been up and down the web and through this site looking for an answer, but still can't get the Autocomplete AJAX control to work. I've gone from trying to include it in an existing site to stripping it right back to a very basic form and it's still not functioning. I'm having a little more luck using Page Methods rather than a local webservice, so here is my code <%@ Page Language="C#" AutoEventWireup="true" CodeFile="droptest.aspx.cs" Inherits="droptest" %> <%@ Register Assembly="AjaxControlToolkit" Namespace="AjaxControlToolkit" TagPrefix="cc1" %> <!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd"> <html xmlns="http://www.w3.org/1999/xhtml"> <head runat="server"> <title></title> </head> <body> <form id="form1" runat="server"> <asp:TextBox ID="TextBox1" runat="server"></asp:TextBox> <asp:ScriptManager ID="ScriptManager1" EnablePageMethods="true" runat="server"> </asp:ScriptManager> <cc1:AutoCompleteExtender ID="AutoCompleteExtender1" runat="server" MinimumPrefixLength="1" ServiceMethod="getResults" TargetControlID="TextBox1"> </cc1:AutoCompleteExtender> </form> </body> </html> using System; using System.Collections.Generic; using System.Linq; using System.Web; using System.Web.UI; using System.Web.UI.WebControls; using System.Web.Script.Services; using System.Web.Services; public partial class droptest : System.Web.UI.Page { protected void Page_Load(object sender, EventArgs e) { } [WebMethod] public string[] getResults(string prefixText, int count) { string[] test = new string[5] { "One", "Two", "Three", "Four", "Five" }; return test; } } Tried to keep things as simple as possible, but all I get is either the autocomplete dropdown with the source of the page (starting with the <! doctype...) letter by letter, or in IE7 it just says "UNDEFINED" all the way down the list. I'm using Visual Web Developer 2008 at the moment, this is running on Localhost. I think I've exhausted all the "Try this..." options I can find, everything from adding in [ScriptMethod] to changing things in Web.Config. Is there anything obviously wrong with this code? Only other thing that may be having an effect is in Global.asax I do a Context.RewritePath to rewrite URLs - does this have any effect on AJAX? Thanks for any help you can give.

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  • Error: java.security.AccessControlException: Access denied

    - by RMD
    Hi, I have to connect to a https url with username and password to read a file. I am not able to connect to the server (see the error log below). I do not have much java experience so I need help with this code. I would really appreciate some help to solve this! Thank you. Raquel CODE: import lotus.domino.; import java.net.; import java.io.*; import javax.net.ssl.HttpsURLConnection; public class JavaAgent extends AgentBase { public void NotesMain() { try { String username = "123"; String password = "456"; String input = username + ":" + password; String encoding = new sun.misc.BASE64Encoder().encode (input.getBytes()); //Open the URL and read the text into a Buffer String urlName = "https://server.org/Export.mvc/GetMeetings?modifiedSince=4/9/2010"; URL url = new URL(urlName); HttpsURLConnection connection = (HttpsURLConnection)url.openConnection(); connection.setRequestMethod("POST"); connection.setRequestProperty("Content-Type", "application/x-www-form-urlencoded"); connection.setRequestProperty("Content-Length", String.valueOf (encoding.length())); connection.setUseCaches(false); connection.setDoInput(true); connection.setDoOutput(true); connection.setAllowUserInteraction(true); connection.setRequestProperty("Authorization", "Basic " + encoding); connection.setRequestProperty("Cookie", "LocationCode=Geneva"); connection.connect(); BufferedReader rd = null; try{ rd = new BufferedReader(new InputStreamReader(connection.getInputStream())); } catch (IOException e) { System.out.println("Read failed"); System.exit(-1); } String line; while((line = rd.readLine()) != null) { System.out.println(line.toString()); } rd.close(); connection.disconnect(); } catch(Exception e) { e.printStackTrace(); } } } LOG: java.security.AccessControlException: Access denied (java.lang.RuntimePermission exitVM.-1) at java.security.AccessController.checkPermission(AccessController.java:108) at java.lang.SecurityManager.checkPermission(SecurityManager.java:532) at COM.ibm.JEmpower.applet.AppletSecurity.superDotCheckPermission(AppletSecurity.java:1449) at COM.ibm.JEmpower.applet.AppletSecurity.checkRuntimePermission(AppletSecurity.java:1311) at COM.ibm.JEmpower.applet.AppletSecurity.checkPermission(AppletSecurity.java:1611) at COM.ibm.JEmpower.applet.AppletSecurity.checkPermission(AppletSecurity.java:1464) at java.lang.SecurityManager.checkExit(SecurityManager.java:744) at java.lang.Runtime.exit(Runtime.java:99) at java.lang.System.exit(System.java:275) at JavaAgent.NotesMain(Unknown Source) at lotus.domino.AgentBase.runNotes(Unknown Source) at lotus.domino.NotesThread.run(Unknown Source)

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  • jquery - loading inline javascript via AJAX

    - by yaya3
    I have thrown together a quick prototype to try and establish a few very basic truths regarding what inline JavaScript can do when it is loaded with AJAX: index.html <html> <head> <script src="http://ajax.googleapis.com/ajax/libs/jquery/1/jquery.min.js"></script> </head> <body> <script type="text/javascript"> $('p').css('color','white'); alert($('p').css('color')); // DISPLAYS FIRST but is "undefined" $(document).ready(function(){ $('#ajax-loaded-content-wrapper').load('loaded-by-ajax.html', function(){ $('p').css('color','grey'); alert($('p').css('color')); // DISPLAYS LAST (as expected) }); $('p').css('color','purple'); alert($('p').css('color')); // DISPLAYS SECOND }); </script> <p>Content not loaded by ajax</p> <div id="ajax-loaded-content-wrapper"> </div> </body> </html> loaded-by-ajax.html <p>Some content loaded by ajax</p> <script type="text/javascript"> $('p').css('color','yellow'); alert($('p').css('color')); // DISPLAYS THIRD $(document).ready(function(){ $('p').css('color','pink'); alert($('p').css('color')); // DISPLAYS FOURTH }); </script> <p>Some content loaded by ajax</p> <script type="text/javascript"> $(document).ready(function(){ $('p').css('color','blue'); alert($('p').css('color')); // DISPLAYS FIFTH }); $('p').css('color','green'); alert($('p').css('color')); // DISPLAYS SIX </script> <p>Some content loaded by ajax</p> Notes: a) All of the above (except the first) successfully change the colour of all the paragraphs (in firefox 3.6.3). b) I've used alert instead of console.log as console is undefined when called in the 'loaded' HTML. Truths(?): $(document).ready() does not treat the 'loaded' HTML as a new document, or reread the entire DOM tree including the loaded HTML, it is pointless inside AJAX loaded content JavaScript that is contained inside 'loaded' HTML can effect the style of existing DOM nodes One can successfully use the jQuery library inside 'loaded' HTML to effect the style of existing DOM nodes One can not use the firebug inside 'loaded' HTML can effect the existing DOM (proven by Note a) Am I correct in deriving these 'truths' from my tests (test validity)? If not, how would you test for these?

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  • Git for Websites / post-receive / Separation of Test and Production Sites

    - by Walt W
    Hi all, I'm using Git to manage my website's source code and deployment, and currently have the test and live sites running on the same box. Following this resource http://toroid.org/ams/git-website-howto originally, I came up with the following post-receive hook script to differentiate between pushes to my live site and pushes to my test site: while read ref do #echo "Ref updated:" #echo $ref -- would print something like example at top of file result=`echo $ref | gawk -F' ' '{ print $3 }'` if [ $result != "" ]; then echo "Branch found: " echo $result case $result in refs/heads/master ) git --work-tree=c:/temp/BLAH checkout -f master echo "Updated master" ;; refs/heads/testbranch ) git --work-tree=c:/temp/BLAH2 checkout -f testbranch echo "Updated testbranch" ;; * ) echo "No update known for $result" ;; esac fi done echo "Post-receive updates complete" However, I have doubts that this is actually safe :) I'm by no means a Git expert, but I am guessing that Git probably keeps track of the current checked-out branch head, and this approach probably has the potential to confuse it to no end. So a few questions: IS this safe? Would a better approach be to have my base repository be the test site repository (with corresponding working directory), and then have that repository push changes to a new live site repository, which has a corresponding working directory to the live site base? This would also allow me to move the production to a different server and keep the deployment chain intact. Is there something I'm missing? Is there a different, clean way to differentiate between test and production deployments when using Git for managing websites? As an additional note in light of Vi's answer, is there a good way to do this that would handle deletions without mucking with the file system much? Thank you, -Walt PS - The script I came up with for the multiple repos (and am using unless I hear better) is as follows: sitename=`basename \`pwd\`` while read ref do #echo "Ref updated:" #echo $ref -- would print something like example at top of file result=`echo $ref | gawk -F' ' '{ print $3 }'` if [ $result != "" ]; then echo "Branch found: " echo $result case $result in refs/heads/master ) git checkout -q -f master if [ $? -eq 0 ]; then echo "Test Site checked out properly" else echo "Failed to checkout test site!" fi ;; refs/heads/live-site ) git push -q ../Live/$sitename live-site:master if [ $? -eq 0 ]; then echo "Live Site received updates properly" else echo "Failed to push updates to Live Site" fi ;; * ) echo "No update known for $result" ;; esac fi done echo "Post-receive updates complete" And then the repo in ../Live/$sitename (these are "bare" repos with working trees added after init) has the basic post-receive: git checkout -f if [ $? -eq 0 ]; then echo "Live site `basename \`pwd\`` checked out successfully" else echo "Live site failed to checkout" fi

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  • Best practices for developing simple ASP.NET sites (built in controls or JQuery + scripts)

    - by Nix
    I was recently reviewing some code written by two different contractors, both were basic ASP.NET management sites. The sites allowed the user to view and edit data. Pretty much simple CRUD gateways. One group did their best to use built in ASP + AJAX Toolkit controls and did their best to use as many built in controls as possible. I found the code much easier to read and maintain. The other used jQuery and the code is heavily marked up with script blocks which are then used to build pages from javascript files. Which one is more common? The one that basically leveraged embedded HTML markup in scripts controled by javascript files screams readability and maintenance issues? Is this just the way of doing asp dev with jQuery? Assuming the second example happens a lot, are there tools that help facilitate jQuery development with visual studio? Do you think they generated the html somewhere else and just copied it in? Example Script block: <script id="HRPanel" type="text/html"> <table cellpadding='0' cellspacing='0' class="atable"><thead class="mHeader"><tr><th>Name</th><th>Description</th><th>Other</th></thead><tbody> <# for(var i=0; i < hrRows.length; i++) { var r = HRRows[i]; #> <tr><td><#=r.Name#></td><td><#=r.Description#></td><td class="taRight"><#=r.Other#></td></tr> <#}#> </tbody><tfoot><th></th><th></th><th></th></tfoot></table> </script> Then in a separate location (js file) you would see something like this. $("#HRPanel").html($("#HRPanel").parseTemplate({ HRRows: response.something.bah.bah }));

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  • Performing dynamic sorts on EF4 data

    - by Jaxidian
    I'm attempting to perform dynamic sorting of data that I'm putting into grids into our MVC UI. Since MVC is abstracted from everything else via WCF, I've created a couple utility classes and extensions to help with this. The two most important things (slightly simplified) are as follows: public static IQueryable<T> ApplySortOptions<T, TModel, TProperty>(this IQueryable<T> collection, IEnumerable<ISortOption<TModel, TProperty>> sortOptions) where TModel : class { var sortedSortOptions = (from o in sortOptions orderby o.Priority ascending select o).ToList(); var results = collection; foreach (var option in sortedSortOptions) { var currentOption = option; var propertyName = currentOption.Property.MemberWithoutInstance(); var isAscending = currentOption.IsAscending; if (isAscending) { results = from r in results orderby propertyName ascending select r; } else { results = from r in results orderby propertyName descending select r; } } return results; } public interface ISortOption<TModel, TProperty> where TModel : class { Expression<Func<TModel, TProperty>> Property { get; set; } bool IsAscending { get; set; } int Priority { get; set; } } I've not given you the implementation for MemberWithoutInstance() but just trust me in that it returns the name of the property as a string. :-) Following is an example of how I would consume this (using a non-interesting, basic implementation of ISortOption<TModel, TProperty>): var query = from b in CurrentContext.Businesses select b; var sortOptions = new List<ISortOption<Business, object>> { new SortOption<Business, object> { Property = (x => x.Name), IsAscending = true, Priority = 0 } }; var results = query.ApplySortOptions(sortOptions); As I discovered with this question, the problem is specific to my orderby propertyName ascending and orderby propertyName descending lines (everything else works great as far as I can tell). How can I do this in a dynamic/generic way that works properly?

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  • What am I missing about WCF?

    - by Bigtoe
    I've been developing in MS technologies for longer than I care to remember at this stage. When .NET arrived on the scene I thought they hit the nail on the head and with each iteration and version I thought their technologies were getting stronger and stronger and looked forward to each release. However, having had to work with WCF for the last year I must say I found the technology very difficult to work with and understand. Initially it's quite appealing but when you start getting into the guts of it, configuration is a nightmare, having to override behaviours for message sizes, number of objects contained in a messages, the complexity of the security model, disposing of proxies when faulted and finally moving back to defining interfaces in code rather than in XML. It just does not work out of the box and I think it should. We found all of the above issues while either testing ourselves or else when our products were out on site. I do understand the rationale behind it all, but surely they could have come up with simpler implementation mechanism. I suppose what I'm asking is, Am I looking at WCF the wrong way? What strengths does it have over the alternatives? Under what circumstances should I choose to use WCF? OK Folks, Sorry about the delay in responding, work does have a nasty habbit of get in the way somethimes :) Some clarifications My main paint point with WCF I suppose falls down into the following areas While it does work out of the box, your left with some major surprises under the hood. As pointed out above basic things are restricted until they are overridden Size of string than can be passed can't be over 8K Number of objects that can be passed in a single message is restricted Proxies not automatically recovering from failures The amount of configuration while it's there is a good thing, but understanding it all and what to use what and under which circumstances can be difficult to understand. Especially when deploying software on site with different security requirements etc. When talking about configuration, we've had to hide lots of ours in a back-end database because security and network people on-site were trying to change things in configuration files without understanding it. Keeping the configuration of the interfaces in code rather than moving to explicitly defined interfaces in XML, which can be published and consumed by almost anything. I know we can export the XML from the assembley, but it's full of rubbish and certain code generators choke on it. I know the world moves on, I've moved on a number of times over the last (ahem 22 years I've been developing) and am actively using WCF, so don't get me wrong, I do understand what it's for and where it's heading. I just think there should be simplier configuration/deployment options available, easier set-up and better management for configuration (SQL config provider maybe, rahter than just the web.config/app.config files). OK, back to the daily grid. Thanks for all your replies so far. Kind Regards Noel

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  • Fixed point math in c#?

    - by x4000
    Hi there, I was wondering if anyone here knows of any good resources for fixed point math in c#? I've seen things like this (http://2ddev.72dpiarmy.com/viewtopic.php?id=156) and this (http://stackoverflow.com/questions/79677/whats-the-best-way-to-do-fixed-point-math), and a number of discussions about whether decimal is really fixed point or actually floating point (update: responders have confirmed that it's definitely floating point), but I haven't seen a solid C# library for things like calculating cosine and sine. My needs are simple -- I need the basic operators, plus cosine, sine, arctan2, PI... I think that's about it. Maybe sqrt. I'm programming a 2D RTS game, which I have largely working, but the unit movement when using floating-point math (doubles) has very small inaccuracies over time (10-30 minutes) across multiple machines, leading to desyncs. This is presently only between a 32 bit OS and a 64 bit OS, all the 32 bit machines seem to stay in sync without issue, which is what makes me think this is a floating point issue. I was aware from this as a possible issue from the outset, and so have limited my use of non-integer position math as much as possible, but for smooth diagonal movement at varying speeds I'm calculating the angle between points in radians, then getting the x and y components of movement with sin and cos. That's the main issue. I'm also doing some calculations for line segment intersections, line-circle intersections, circle-rect intersections, etc, that also probably need to move from floating-point to fixed-point to avoid cross-machine issues. If there's something open source in Java or VB or another comparable language, I could probably convert the code for my uses. The main priority for me is accuracy, although I'd like as little speed loss over present performance as possible. This whole fixed point math thing is very new to me, and I'm surprised by how little practical information on it there is on google -- most stuff seems to be either theory or dense C++ header files. Anything you could do to point me in the right direction is much appreciated; if I can get this working, I plan to open-source the math functions I put together so that there will be a resource for other C# programmers out there. UPDATE: I could definitely make a cosine/sine lookup table work for my purposes, but I don't think that would work for arctan2, since I'd need to generate a table with about 64,000x64,000 entries (yikes). If you know any programmatic explanations of efficient ways to calculate things like arctan2, that would be awesome. My math background is all right, but the advanced formulas and traditional math notation are very difficult for me to translate into code.

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  • Android app crashes when I change the default xml layout file to another

    - by mib1413456
    I am currently just starting to learn android development and have created a basic "Hello world" app that uses "activity_main.xml" for the default layout. I tried to create a new layout xml file called "new_layout.xml" with a text view, a text field and a button and did the following changes in the MainActivity.java file: setContentView(R.layout.new_layout); I did nothing else expect for adding a new_layout.xml in the res/layout folder, I have tried restarting and cleaning the project but nothing. Below is my activity_main.xml file, new_layout.xml file and MainActivity.java activity_main.xml: <FrameLayout xmlns:android="http://schemas.android.com/apk/res/android" xmlns:tools="http://schemas.android.com/tools" android:id="@+id/container" android:layout_width="match_parent" android:layout_height="match_parent" tools:context="org.example.androidsdk.demo.MainActivity" tools:ignore="MergeRootFrame" /> new_layout.xml: <?xml version="1.0" encoding="utf-8"?> <LinearLayout xmlns:android="http://schemas.android.com/apk/res/android" android:layout_width="match_parent" android:layout_height="match_parent" android:orientation="horizontal" > <TextView android:id="@+id/textView1" android:layout_width="wrap_content" android:layout_height="wrap_content" android:text="TextView" /> <EditText android:id="@+id/editText1" android:layout_width="wrap_content" android:layout_height="wrap_content" android:layout_weight="1" android:ems="10" > <requestFocus /> </EditText> <Button android:id="@+id/button1" android:layout_width="wrap_content" android:layout_height="wrap_content" android:text="Button" /> MainActivity.java file package org.example.androidsdk.demo; import android.app.Activity; import android.app.ActionBar; import android.app.Fragment; import android.os.Bundle; import android.view.LayoutInflater; import android.view.Menu; import android.view.MenuItem; import android.view.View; import android.view.ViewGroup; import android.os.Build; public class MainActivity extends Activity { @Override protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.new_layout); if (savedInstanceState == null) { getFragmentManager().beginTransaction() .add(R.id.container, new PlaceholderFragment()) .commit(); } } @Override public boolean onCreateOptionsMenu(Menu menu) { // Inflate the menu; this adds items to the action bar if it is present. getMenuInflater().inflate(R.menu.main, menu); return true; } @Override public boolean onOptionsItemSelected(MenuItem item) { // Handle action bar item clicks here. The action bar will // automatically handle clicks on the Home/Up button, so long // as you specify a parent activity in AndroidManifest.xml. int id = item.getItemId(); if (id == R.id.action_settings) { return true; } return super.onOptionsItemSelected(item); } /** * A placeholder fragment containing a simple view. */ public static class PlaceholderFragment extends Fragment { public PlaceholderFragment() { } @Override public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) { View rootView = inflater.inflate(R.layout.fragment_main, container, false); return rootView; } } }

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  • active_scaffold routing error

    - by Elizabeth Buckwalter
    If you haven't seen my question yesterday, this is my second rails app. The first went nice and smooth, but this one keeps giving me one random error after another. I installed active_scaffold for this app as well as the last app (the first error, instead of using script/install plugin git://active_scaffold repository, I did script/install plugin http://active_scaffold repository.) I didn't want to spell out basic CRUD on minor models. After the install problems, (before I found the http solution from a windows user when I'm on Linux) I thought I'd try out Hobo. Well, Hobo updated actionmailer, actionpack, activerecord, activeresource, and installed rack. Rails isn't even using the updated versions. But as you can see at the bottom of the trace it's using rack. I have a feeling it has something to do with my futzing around with installing Hobo which I uninstalled. Thanks in advanced. [Edit] I had asked the question over at the ActiveScaffold Group the answer (if you don't want to follow the link) was that this line needed to be added to routes: map.resources :modelName, :active_scaffold => true It doesn't entirely answer my question, since the documentation said nothing about changing routes. But, it works. [/Edit] ActionController::RoutingError in Departments#index Showing vendor/plugins/active_scaffold/frontends/default/views/_list_header.html.erb where line #8 raised: No route matches {:_method=:get, :action="show_search", :controller="departments"} Extracted source (around line #8): 5: <% next if controller.respond_to? link.security_method and !controller.send(link.security_method) -%> 6: <% next if link.action == 'new' && params[:nested].nil? && active_scaffold_config.list.always_show_create %> 7: <% next if link.action == 'show_search' && active_scaffold_config.list.always_show_search %> 8: <%= render_action_link(link, new_params) -%> 9: <% end -%> 10: 11: <%= loading_indicator_tag(:action => :table) %> Trace of template inclusion: vendor/plugins/active_scaffold/frontends/default/views/list.html.erb Full Trace It was taking forever to format it. I'm still not fully conversant in SO's formatting (sometimes the server is down. reboots are reinstalls. it's a play server)

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  • Non-linear regression models in PostgreSQL using R

    - by Dave Jarvis
    Background I have climate data (temperature, precipitation, snow depth) for all of Canada between 1900 and 2009. I have written a basic website and the simplest page allows users to choose category and city. They then get back a very simple report (without the parameters and calculations section): The primary purpose of the web application is to provide a simple user interface so that the general public can explore the data in meaningful ways. (A list of numbers is not meaningful to the general public, nor is a website that provides too many inputs.) The secondary purpose of the application is to provide climatologists and other scientists with deeper ways to view the data. (Using too many inputs, of course.) Tool Set The database is PostgreSQL with R (mostly) installed. The reports are written using iReport and generated using JasperReports. Poor Model Choice Currently, a linear regression model is applied against annual averages of daily data. The linear regression model is calculated within a PostgreSQL function as follows: SELECT regr_slope( amount, year_taken ), regr_intercept( amount, year_taken ), corr( amount, year_taken ) FROM temp_regression INTO STRICT slope, intercept, correlation; The results are returned to JasperReports using: SELECT year_taken, amount, year_taken * slope + intercept, slope, intercept, correlation, total_measurements INTO result; JasperReports calls into PostgreSQL using the following parameterized analysis function: SELECT year_taken, amount, measurements, regression_line, slope, intercept, correlation, total_measurements, execute_time FROM climate.analysis( $P{CityId}, $P{Elevation1}, $P{Elevation2}, $P{Radius}, $P{CategoryId}, $P{Year1}, $P{Year2} ) ORDER BY year_taken This is not an optimal solution because it gives the false impression that the climate is changing at a slow, but steady rate. Questions Using functions that take two parameters (e.g., year [X] and amount [Y]), such as PostgreSQL's regr_slope: What is a better regression model to apply? What CPAN-R packages provide such models? (Installable, ideally, using apt-get.) How can the R functions be called within a PostgreSQL function? If no such functions exist: What parameters should I try to obtain for functions that will produce the desired fit? How would you recommend showing the best fit curve? Keep in mind that this is a web app for use by the general public. If the only way to analyse the data is from an R shell, then the purpose has been defeated. (I know this is not the case for most R functions I have looked at so far.) Thank you!

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  • Need to set cursor position to the end of a contentEditable div, issue with selection and range obje

    - by DavidR
    I'm forgetting about cross-browser compatibility for the moment, I just want this to work. What I'm doing is trying to modify a script (and you probably don't need to know this) located at typegreek.com The basic script is found here. Basically what it does is when you type in characters, it converts the character your are typing into greek characters and prints it onto the screen. What I'm trying to do is to get it to work on contentEditable div's (It only works for Textareas) My issue is with this one function: The user types a key, it get's converted to a greek key, and goes to a function, it gets sorted through some if's, and where it ends up is where I can add div support. Here is what I have so far, myField is the div, myValue is the greek character. //Get selection object... var userSelection if (window.getSelection) {userSelection = window.getSelection();} else if (document.selection) {userSelection = document.selection.createRange();} //Now get the cursor position information... var startPos = userSelection.anchorOffset; var endPos = userSelection.focusOffset; var cursorPos = endPos; //Needed later when reinserting the cursor... var rangeObj = userSelection.getRangeAt(0) var container = rangeObj.startContainer //Now take the content from pos 0 -> cursor, add in myValue, then insert everything after myValue to the end of the line. myField.textContent = myField.textContent.substring(0, startPos) + myValue + myField.textContent.substring(endPos, myField.textContent.length); //Now the issue is, this updates the string, and returns the cursor to the beginning of the div. //so that at the next keypress, the character is inserted into the beginning of the div. //So we need to reinsert the cursor where it was. //Re-evaluate the cursor position, taking into account the added character. var cursorPos = endPos + myValue.length; //Set the caracter position. rangeObj.setStart(container,cursorPos) Now, this works only as long as I don't type more than the size of the original text. Say I had 30 characters in the div before hand. If I type more than that 30, it adds character 31, but places the cursor back at 30. I can type character 32 at pos.31, then character 33 at pos.32, but if I try to put character 34 in, it adds the character, and sets the cursor back at 32. The issue is that the function for adding the new character screws up if cursorPos is greater than what is defined in the range. Any ideas?

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  • Can I Number a GroupTemplate or ItemTemplate?

    - by Atomiton
    I would like to use a GroupTemplate to separate a list of items into groups. However, I need each Group to be numbered sequentially so I can link to them and implement some JS paging. I'm binding to an IEnumerable Here's some pseudo code. I would like the output to look like this: <a href="#group1">Go to Group 1<a> <a href="#group2">Go to Group 2<a> <a href="#group3">Go to Group 3<a> <ul id="group1"> <li>Item</li> <li>Item</li> <li>Item</li> </ul> <ul id="group2"> <li>Item</li> <li>Item</li> <li>Item</li> </ul> <ul id="group3"> <li>Item</li> <li>Item</li> <li>Item</li> </ul> Is this easy to do in a ListView, using GroupTemplate and ItemTemplate? <asp:ListView ID="lv" runat="server" GroupPlaceholderID="groupPlaceholder"> <LayoutTemplate> <asp:PlaceHolder ID="groupPlaceholder" runat="server"></asp:PlaceHolder> </LayoutTemplate> <GroupTemplate> <ul id="<!-- group-n goes here -->"> <asp:PlaceHolder ID="itemPlaceholder" runat="server"></asp:PlaceHolder> </ul> </GroupTemplate> <ItemTemplate> <li>Item</li> </ItemTemplate> </asp:ListView> I can get the number of groups to do the links at the top from the Datasource and basic math, but how do I get id="groupN" number into the template?

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  • How can I use Web Services Core to send a complex type as a parameter to a SOAP API method

    - by Matthew Brindley
    I don't do much Cocoa programming, so I'm probably missing something obvious, so please excuse the basic question. I have a SOAP method that expects a complex type as a paramater. Here's some WSDL: <s:element name="SaveTestResult"> <s:complexType> <s:sequence> <s:element minOccurs="0" maxOccurs="1" name="result" type="tns:TestItemResponse" /> </s:sequence> </s:complexType> </s:element> Here's the definition of the complex type "TestItemResponse": <s:complexType name="TestItemResponse"> <s:sequence> <s:element minOccurs="1" maxOccurs="1" name="TestItemRequestId" type="s:int" /> <s:element minOccurs="1" maxOccurs="1" name="ExternalId" type="s:int" /> <s:element minOccurs="0" maxOccurs="1" name="ApiId" type="s:string" /> <s:element minOccurs="0" maxOccurs="1" name="InboxGuid" type="s:string" /> <s:element minOccurs="0" maxOccurs="1" name="SpamResult" type="tns:SpamResult" /> <s:element minOccurs="0" maxOccurs="1" name="ResultImageSet" type="tns:ResultImageSet" /> <s:element minOccurs="1" maxOccurs="1" name="ExclusiveUseMailAccountId" type="s:int" /> <s:element minOccurs="1" maxOccurs="1" name="State" type="tns:TestItemResponseState" /> <s:element minOccurs="0" maxOccurs="1" name="ErrorShortDescription" type="s:string" /> <s:element minOccurs="0" maxOccurs="1" name="ErrorFullDescription" type="s:string" /> </s:sequence> </s:complexType> I've been using Web Services Core to call a SOAP API method that requires a simple string param, that works great. That same method returns a complex type which WSC converted into nested NSDictionaries, so no problems there. So I assumed I'd be able to convert my local TestItemResponse class into an NSDictionary and then use that as the complex type param. It almost worked, but unfortunately WSC set the object's type as "Dictionary", instead of "TestItemResponse", and the server complained. <TestItemResponse xsi:type=\"SOAP-ENC:Dictionary\"> <ErrorFullDescription xsi:type=\"xsd:string\">foo</ErrorFullDescription> ... I can't seem to find anything that allows you to override the type WSC assigns to the element in the SOAP XML. I've been using code adapted from here, I'm happy to list it, it's just quite long and this is already the longest SO question I've ever posted.

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  • Determining what frequencies correspond to the x axis in aurioTouch sample application

    - by eagle
    I'm looking at the aurioTouch sample application for the iPhone SDK. It has a basic spectrum analyzer implemented when you choose the "FFT" option. One of the things the app is lacking is X axis labels (i.e. the frequency labels). In the aurioTouchAppDelegate.mm file, in the function - (void)drawOscilloscope at line 652, it has the following code: if (displayMode == aurioTouchDisplayModeOscilloscopeFFT) { if (fftBufferManager->HasNewAudioData()) { if (fftBufferManager->ComputeFFT(l_fftData)) [self setFFTData:l_fftData length:fftBufferManager->GetNumberFrames() / 2]; else hasNewFFTData = NO; } if (hasNewFFTData) { int y, maxY; maxY = drawBufferLen; for (y=0; y<maxY; y++) { CGFloat yFract = (CGFloat)y / (CGFloat)(maxY - 1); CGFloat fftIdx = yFract * ((CGFloat)fftLength); double fftIdx_i, fftIdx_f; fftIdx_f = modf(fftIdx, &fftIdx_i); SInt8 fft_l, fft_r; CGFloat fft_l_fl, fft_r_fl; CGFloat interpVal; fft_l = (fftData[(int)fftIdx_i] & 0xFF000000) >> 24; fft_r = (fftData[(int)fftIdx_i + 1] & 0xFF000000) >> 24; fft_l_fl = (CGFloat)(fft_l + 80) / 64.; fft_r_fl = (CGFloat)(fft_r + 80) / 64.; interpVal = fft_l_fl * (1. - fftIdx_f) + fft_r_fl * fftIdx_f; interpVal = CLAMP(0., interpVal, 1.); drawBuffers[0][y] = (interpVal * 120); } cycleOscilloscopeLines(); } } From my understanding, this part of the code is what is used to decide which magnitude to draw for each frequency in the UI. My question is how can I determine what frequency each iteration (or y value) represents inside the for loop. For example, if I want to know what the magnitude is for 6kHz, I'm thinking of adding a line similar to the following: if (yValueRepresentskHz(y, 6)) NSLog(@"The magnitude for 6kHz is %f", (interpVal * 120)); Please note that although they chose to use the variable name y, from what I understand, it actually represents the x-axis in the visual graph of the spectrum analyzer, and the value of the drawBuffers[0][y] represents the y-axis.

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  • OSGI classcast exception on felix

    - by Nico
    Hi, i'm fairly new to osgi and am trying to get a functional proof of concept together. The setup is that my common api is created in a bundle creatively named common-api.jar with no bundle activator, but it exports all it's interfaces. the one of interest in this situation is DatabaseService.java. I then have a Second bundle called systemx-database-service. That implements the database service interface. this works fine as in the activator of the implementation bundle i test the connection to the database and select some arbitraty values. I also register the service i want to be available to the other bundle's like so: context.registerService(DatabaseService.class.getName(), new SystemDatabaseServiceImpl(context), new Properties()); The basic idea being when you look for a service reference for a Database service you'll get back the SystemDatabaseService implementation. When i do a inspect service the output it this: -> inspect s c 69 System Database Service (69) provides services: ---------------------------------------------- objectClass = za.co.xxx.xxx.common.api.DatabaseService service.id = 39 which would lead me to believe that if i do this in a test bundle: context.getService(context.getServiceReference(DatabaseService.class)); i should get back an instance of DatabaseService.class, but alas no such luck. it simply seems like it cannot find the service. stick with me here my story gets stranger. figuring there is no where to go but up i wrote this monstrosity: for (Bundle bundle : bundles) { if (bundle.getSymbolicName().equals("za.co.xxx.xxx.database-service")) { ServiceReference[] registeredServices = bundle.getRegisteredServices(); for (ServiceReference ref : registeredServices) { DatabaseService service = (DatabaseService) context.getService(ref); // use service here. } } } } now i can actually see the service reference, but i get this error java.lang.ClassCastException: za.co.xxx.xxx.database.service.impl.SystemDatabaseServiceImpl cannot be cast to za.co.xxx.xx.common.api.DatabaseService which is crazy since the implementation clearly implements the interface! Any help would be appreciated. Please keep in mind i'm very new at the osgi way of thinking so my whole approach here might be flawed. oh. if anyone wants the manifests i can post them. and i'm using the maven-bnd-plugin to build and executing on felix. thanks Nico

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  • Minimalistic tools for developer documentation

    - by Pekka
    I am currently working on a large PHP CMS / Framework and documenting it extensively as I go along. In addition to phpdoc-style inline comments, I need to document XML structures, details on concepts and practices, write HOWTOs and so on. At the moment, I am using simple OpenOffice documents for that, but I'm unhappy with it and looking for a "real" documentation system. So, I am looking for recommendations for robust, minimalistic, easy-to-use documentation software. I have tried a number of Wikis, most prominently Dokuwiki. I like the open-minded approach, the freedom in editing, and the simplicity, but they provide little support in structuring a multi-chapter documentation, and make basic reorganisation tasks very difficult (e.g. moving pages to a different namespace). Working with the plugins is Cumbersome, and they are not really easy to use. Open Source would be a plus but is not a requirement. Thanks for all the suggestions. I have not had time to look into each one in detail. I will be trying Sphinx, especially because it provides so much support for a good structure. I may update this post later when I'm done and report how it worked out. The suggestions Trac's built-in wiki which is great but for my taste provides too little support for keeping a structure - it's perfect though for "normal", smaller size project documentation Markdown my current favourite because of its minimalism, however not sure yet whether maintaining a structure will be easy enough. A Markdown-Based system would of course be very easy to extend, e.g. to look up cross references from the project's code base. Of course it would be great to find something that already has that out of the box. The DocBook format and to edit, the commercial Oxygen XML Editor - a great standard for building documentation, no doubt. Maybe too "technical" for my purposes as I need something to open quickly, write into and go on coding. Still always worth a mention. Sphinx an Open Source, Python based documentation generator, promising structured documentation and extensive cross-referencing. Interesting and will take a look. Confluence a commercial but very affordable Wiki. XWiki, an Open Source playing in Confluence's league with numerous extensions and connectors to Eclipse and Microsoft Office. TiddlyWiki an open-source Wiki.

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  • Which StackOverflow-style MarkDown (WMD) javascript editor should I use?

    - by Edan Maor
    Background I'm working on an application which requires user-entered content, and I've decided to use a StackOverflow-style MarkDown editor. After researching this topic for the last few days, I realize there are numerous forks of the base WMD editor, some with a few basic enhancements and some with serious differences from the StackOverflow one. Since this will be the heart of the application, I'd like to start with the best code base I can. I'd be happy if anyone can recommend which one of the many solutions out there best fits my needs. Below is requirements, plus what I've managed to find already. I'm hoping this question will help me decide which version to go with, and maybe help me discover a port out there that's an even better fit for my needs. The requirements for my project Live Preview Multiple editors on the same page (not know how many in advance, since the user can dynamically add another editing box). Ability to extend with extra buttons (I'd like a button to upload a picture, instead of just adding an img url). Ability to dynamically show/hide the edit box (and only see the preview box). Not an absolute must, but I'd prefer to stick as close to StackOverflow's look and feel, since it's well known. Don't know if this matters, but the backend is written in Django. Editors I've looked at Here are a few of the code bases I've looked at, with thoughts. Obviously, I might be missing another solution out there. The derobins version. From what I can tell, this is the official StackOverflow version. Seems like it doesn't support multiple editors on one page. JQuery.MarkEdit. Looks very good, but is pretty different from the StackOverflow version. MooWMD. Looks like the winner right now, but I'm a little concerned since it looks less active/hackable than MarkEdit. The wmd-new version. Not sure, looks like an old codebase without much use. The SocialSite branch. Seems like it's not for public use.

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  • Correlated SQL Join Query from multiple tables

    - by SooDesuNe
    I have two tables like the ones below. I need to find what exchangeRate was in effect at the dateOfPurchase. I've tried some correlated sub queries, but I'm having difficulty getting the correlated record to be used in the sub queries. I expect a solution will need to follow this basic outline: SELECT only the exchangeRates for the applicable countryCode From 1. SELECT the newest exchangeRate less than the dateOfPurchase Fill in the query table with all the fields from 2. and the purchasesTable. My Tables: purchasesTable: > dateOfPurchase | costOfPurchase | countryOfPurchase > 29-March-2010 | 20.00 | EUR > 29-March-2010 | 3000 | JPN > 30-March-2010 | 50.00 | EUR > 30-March-2010 | 3000 | JPN > 30-March-2010 | 2000 | JPN > 31-March-2010 | 100.00 | EUR > 31-March-2010 | 125.00 | EUR > 31-March-2010 | 2000 | JPN > 31-March-2010 | 2400 | JPN costOfPurchase is in whatever the local currency is for a given countryCode exchangeRateTable > effectiveDate | countryCode | exchangeRate > 29-March-2010 | JPN | 90 > 29-March-2010 | EUR | 1.75 > 30-March-2010 | JPN | 92 > 31-March-2010 | JPN | 91 The results of the query that I'm looking for: > dateOfPurchase | costOfPurchase | countryOfPurchase | exchangeRate > 29-March-2010 | 20.00 | EUR | 1.75 > 29-March-2010 | 3000 | JPN | 90 > 30-March-2010 | 50.00 | EUR | 1.75 > 30-March-2010 | 3000 | JPN | 92 > 30-March-2010 | 2000 | JPN | 92 > 31-March-2010 | 100.00 | EUR | 1.75 > 31-March-2010 | 125.00 | EUR | 1.75 > 31-March-2010 | 2000 | JPN | 91 > 31-March-2010 | 2400 | JPN | 91 So for example in the results, the exchange rate, in effect for EUR on 31-March was 1.75. I'm using Access, but a MySQL answer would be fine too. UPDATE: Modification to Allan's answer: SELECT dateOfPurchase, costOfPurchase, countryOfPurchase, exchangeRate FROM purchasesTable p LEFT OUTER JOIN (SELECT e1.exchangeRate, e1.countryCode, e1.effectiveDate, min(e2.effectiveDate) AS enddate FROM exchangeRateTable e1 LEFT OUTER JOIN exchangeRateTable e2 ON e1.effectiveDate < e2.effectiveDate AND e1.countryCode = e2.countryCode GROUP BY e1.exchangeRate, e1.countryCode, e1.effectiveDate) e ON p.dateOfPurchase >= e.effectiveDate AND (p.dateOfPurchase < e.enddate OR e.enddate is null) AND p.countryOfPurchase = e.countryCode I had to make a couple small changes.

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  • Why does PostgresQL query performance drop over time, but restored when rebuilding index

    - by Jim Rush
    According to this page in the manual, indexes don't need to be maintained. However, we are running with a PostgresQL table that has a continuous rate of updates, deletes and inserts that over time (a few days) sees a significant query degradation. If we delete and recreate the index, query performance is restored. We are using out of the box settings. The table in our test is currently starting out empty and grows to half a million rows. It has a fairly large row (lots of text fields). We are search is based of an index, not the primary key (I've confirmed the index is being used, at least under normal conditions) The table is being used as a persistent store for a single process. Using PostgresQL on Windows with a Java client I'm willing to give up insert and update performance to keep up the query performance. We are considering rearchitecting the application so that data is spread across various dynamic tables in a manner that allows us to drop and rebuild indexes periodically without impacting the application. However, as always, there is a time crunch to get this to work and I suspect we are missing something basic in our configuration or usage. We have considered forcing vacuuming and rebuild to run at certain times, but I suspect the locking period for such an action would cause our query to block. This may be an option, but there are some real-time (windows of 3-5 seconds) implications that require other changes in our code. Additional information: Table and index CREATE TABLE icl_contacts ( id bigint NOT NULL, campaignfqname character varying(255) NOT NULL, currentstate character(16) NOT NULL, xmlscheduledtime character(23) NOT NULL, ... 25 or so other fields. Most of them fixed or varying character fiel ... CONSTRAINT icl_contacts_pkey PRIMARY KEY (id) ) WITH (OIDS=FALSE); ALTER TABLE icl_contacts OWNER TO postgres; CREATE INDEX icl_contacts_idx ON icl_contacts USING btree (xmlscheduledtime, currentstate, campaignfqname); Analyze: Limit (cost=0.00..3792.10 rows=750 width=32) (actual time=48.922..59.601 rows=750 loops=1) - Index Scan using icl_contacts_idx on icl_contacts (cost=0.00..934580.47 rows=184841 width=32) (actual time=48.909..55.961 rows=750 loops=1) Index Cond: ((xmlscheduledtime < '2010-05-20T13:00:00.000'::bpchar) AND (currentstate = 'SCHEDULED'::bpchar) AND ((campaignfqname)::text = '.main.ee45692a-6113-43cb-9257-7b6bf65f0c3e'::text)) And, yes, I am aware there there are a variety of things we could do to normalize and improve the design of this table. Some of these options may be available to us. My focus in this question is about understanding how PostgresQL is managing the index and query over time (understand why, not just fix). If it were to be done over or significantly refactored, there would be a lot of changes.

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  • Outlook Marking Email as Junk Email

    - by robertabead
    I know. I sound like a spammer but these emails are completely legitimate email confirmations for people that have signed up for an account on this website we developed. These emails all make it through to various mail providers (gmail, yahoo, aol, hotmail/live) but they always get directed into the Outlook Junk Email folder. I am have tried using Zend Framework mail, PEAR Mail and phpMailer. All of those methods result in the same thing happening. This seemed to start happening after Microsoft released their update to the Outlook Junk Email filter in January of this year. Following is the code in question: include_once('Mail.php'); include_once('Mail/mime.php'); $hdrs = array( 'From' => "Membership <[email protected]>", 'Subject' => 'Test Email', 'Reply-To'=> "[email protected]", 'Message-ID'=> "<" . str_pad(rand(0,12345678),8,'0',STR_PAD_LEFT) . "@mail.example.com>", 'Date'=> date("D, j M Y H:i:s O",time()), 'To'=> '[email protected]' ); $params = array('host'=>'mail.example.com','auth'=>false,'localhost' => 'www.example.com','debug'=>false); $crlf = "\n"; $mime = new Mail_mime($crlf); $mime->setTXTBody("TEST"); $mime->setHTMLBody("<html>\n<body>\nTest\n</body>\n</html>"); $body = $mime->get(); $hdrs = $mime->headers($hdrs); $mail =& Mail::factory('smtp',$params); $t=$mail->send('[email protected]', $hdrs, $body); As you can see we are using the PEAR Mail functionality in this test. This is the most basic test we could run and the above generated email gets dumped into the Outlook Junk Email folder. We have reverse DNS on the mail server and it matches the forward DNS, SPF and DKIM are set up and there is nothing "spammy" with the above content. Can anybody see something with the above code that could cause Outlook to mark it as Junk? Thanks!

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  • Symfony 1.4 Layout footer glitch: Footer div is echoed out with $sf_content

    - by Parijat Kalia
    I have a very simple Layout for my application. A header, the main content, and a footer. Semantically, they are rendered like this: <body> <div id = "header"> </div> <div id = "content"> </div> <div id = "footer"> </div> </body> The corresponding CSS is very basic as well: #header{ width:100%; min-height:10%; } #center{ width:100%; min-height:80%; } #footer{ width:100%; min-height:10%: } As you would know in the layout page, here is how the content is rendered: <div id= "content"> <?php echo $sf_content; ?> </div> All of the above is very fine and it renders itself as it is supposed to. But there is a glitch with this, the moment i put in <?php echo $sf_content; ?> the footer is included as part of the content and not as a div that is after the #content markup. Essentially, I get this: <div id = "header"></div> <div id = "content> <div id ="symfony_template_to_be_rendered"> <!-- all web application related content like forms etc. --> </div> <div id = "footer">Footer material </div> </div> As you can see, for some weird reason, the footer moved up along with the symfony content. Clearly this is a glitch because if I remove the php hash $sf_content part from the div tags in my layouts, then the footer renders itself as and where it should be and everything takes up the required dimensions. What's going on here?

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  • NSStringWithFormat Swizzled to allow missing format numbered args

    - by coneybeare
    Based on this SO question asked a few hours ago, I have decided to implement a swizzled method that will allow me to take a formatted NSString as the format arg into stringWithFormat, and have it not break when omitting one of the numbered arg references (%1$@, %2$@) I have it working, but this is the first copy, and seeing as this method is going to be potentially called hundreds of thousands of times per app run, I need to bounce this off of some experts to see if this method has any red flags, major performance hits, or optimizations #define NUMARGS(...) (sizeof((int[]){__VA_ARGS__})/sizeof(int)) @implementation NSString (UAFormatOmissions) + (id)uaStringWithFormat:(NSString *)format, ... { if (format != nil) { va_list args; va_start(args, format); // $@ is an ordered variable (%1$@, %2$@...) if ([format rangeOfString:@"$@"].location == NSNotFound) { //call apples method NSString *s = [[[NSString alloc] initWithFormat:format arguments:args] autorelease]; va_end(args); return s; } NSMutableArray *newArgs = (NSMutableArray *)[NSMutableArray arrayWithCapacity:NUMARGS(args)]; id arg = nil; int i = 1; while (arg = va_arg(args, id)) { NSString *f = (NSString *)[NSString stringWithFormat:@"%%%d\$\@", i]; i++; if ([format rangeOfString:f].location == NSNotFound) continue; else [newArgs addObject:arg]; } va_end(args); char *newArgList = (char *)malloc(sizeof(id) * [newArgs count]); [newArgs getObjects:(id *)newArgList]; NSString* result = [[[NSString alloc] initWithFormat:format arguments:newArgList] autorelease]; free(newArgList); return result; } return nil; } The basic algorithm is: search the format string for the %1$@, %2$@ variables by searching for %@ if not found, call the normal stringWithFormat and return else, loop over the args if the format has a position variable (%i$@) for position i, add the arg to the new arg array else, don't add the arg take the new arg array, convert it back into a va_list, and call initWithFormat:arguments: to get the correct string. The idea is that I would run all [NSString stringWithFormat:] calls through this method instead. This might seem unnecessary to many, but click on to the referenced SO question (first line) to see examples of why I need to do this. Ideas? Thoughts? Better implementations? Better Solutions?

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  • Troubleshooting latency spikes on ESXi NFS datastores

    - by exo_cw
    I'm experiencing fsync latencies of around five seconds on NFS datastores in ESXi, triggered by certain VMs. I suspect this might be caused by VMs using NCQ/TCQ, as this does not happen with virtual IDE drives. This can be reproduced using fsync-tester (by Ted Ts'o) and ioping. For example using a Grml live system with a 8GB disk: Linux 2.6.33-grml64: root@dynip211 /mnt/sda # ./fsync-tester fsync time: 5.0391 fsync time: 5.0438 fsync time: 5.0300 fsync time: 0.0231 fsync time: 0.0243 fsync time: 5.0382 fsync time: 5.0400 [... goes on like this ...] That is 5 seconds, not milliseconds. This is even creating IO-latencies on a different VM running on the same host and datastore: root@grml /mnt/sda/ioping-0.5 # ./ioping -i 0.3 -p 20 . 4096 bytes from . (reiserfs /dev/sda): request=1 time=7.2 ms 4096 bytes from . (reiserfs /dev/sda): request=2 time=0.9 ms 4096 bytes from . (reiserfs /dev/sda): request=3 time=0.9 ms 4096 bytes from . (reiserfs /dev/sda): request=4 time=0.9 ms 4096 bytes from . (reiserfs /dev/sda): request=5 time=4809.0 ms 4096 bytes from . (reiserfs /dev/sda): request=6 time=1.0 ms 4096 bytes from . (reiserfs /dev/sda): request=7 time=1.2 ms 4096 bytes from . (reiserfs /dev/sda): request=8 time=1.1 ms 4096 bytes from . (reiserfs /dev/sda): request=9 time=1.3 ms 4096 bytes from . (reiserfs /dev/sda): request=10 time=1.2 ms 4096 bytes from . (reiserfs /dev/sda): request=11 time=1.0 ms 4096 bytes from . (reiserfs /dev/sda): request=12 time=4950.0 ms When I move the first VM to local storage it looks perfectly normal: root@dynip211 /mnt/sda # ./fsync-tester fsync time: 0.0191 fsync time: 0.0201 fsync time: 0.0203 fsync time: 0.0206 fsync time: 0.0192 fsync time: 0.0231 fsync time: 0.0201 [... tried that for one hour: no spike ...] Things I've tried that made no difference: Tested several ESXi Builds: 381591, 348481, 260247 Tested on different hardware, different Intel and AMD boxes Tested with different NFS servers, all show the same behavior: OpenIndiana b147 (ZFS sync always or disabled: no difference) OpenIndiana b148 (ZFS sync always or disabled: no difference) Linux 2.6.32 (sync or async: no difference) It makes no difference if the NFS server is on the same machine (as a virtual storage appliance) or on a different host Guest OS tested, showing problems: Windows 7 64 Bit (using CrystalDiskMark, latency spikes happen mostly during preparing phase) Linux 2.6.32 (fsync-tester + ioping) Linux 2.6.38 (fsync-tester + ioping) I could not reproduce this problem on Linux 2.6.18 VMs. Another workaround is to use virtual IDE disks (vs SCSI/SAS), but that is limiting performance and the number of drives per VM. Update 2011-06-30: The latency spikes seem to happen more often if the application writes in multiple small blocks before fsync. For example fsync-tester does this (strace output): pwrite(3, "aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa"..., 1048576, 0) = 1048576 fsync(3) = 0 ioping does this while preparing the file: [lots of pwrites] pwrite(3, "********************************"..., 4096, 1036288) = 4096 pwrite(3, "********************************"..., 4096, 1040384) = 4096 pwrite(3, "********************************"..., 4096, 1044480) = 4096 fsync(3) = 0 The setup phase of ioping almost always hangs, while fsync-tester sometimes works fine. Is someone capable of updating fsync-tester to write multiple small blocks? My C skills suck ;) Update 2011-07-02: This problem does not occur with iSCSI. I tried this with the OpenIndiana COMSTAR iSCSI server. But iSCSI does not give you easy access to the VMDK files so you can move them between hosts with snapshots and rsync. Update 2011-07-06: This is part of a wireshark capture, captured by a third VM on the same vSwitch. This all happens on the same host, no physical network involved. I've started ioping around time 20. There were no packets sent until the five second delay was over: No. Time Source Destination Protocol Info 1082 16.164096 192.168.250.10 192.168.250.20 NFS V3 WRITE Call (Reply In 1085), FH:0x3eb56466 Offset:0 Len:84 FILE_SYNC 1083 16.164112 192.168.250.10 192.168.250.20 NFS V3 WRITE Call (Reply In 1086), FH:0x3eb56f66 Offset:0 Len:84 FILE_SYNC 1084 16.166060 192.168.250.20 192.168.250.10 TCP nfs > iclcnet-locate [ACK] Seq=445 Ack=1057 Win=32806 Len=0 TSV=432016 TSER=769110 1085 16.167678 192.168.250.20 192.168.250.10 NFS V3 WRITE Reply (Call In 1082) Len:84 FILE_SYNC 1086 16.168280 192.168.250.20 192.168.250.10 NFS V3 WRITE Reply (Call In 1083) Len:84 FILE_SYNC 1087 16.168417 192.168.250.10 192.168.250.20 TCP iclcnet-locate > nfs [ACK] Seq=1057 Ack=773 Win=4163 Len=0 TSV=769110 TSER=432016 1088 23.163028 192.168.250.10 192.168.250.20 NFS V3 GETATTR Call (Reply In 1089), FH:0x0bb04963 1089 23.164541 192.168.250.20 192.168.250.10 NFS V3 GETATTR Reply (Call In 1088) Directory mode:0777 uid:0 gid:0 1090 23.274252 192.168.250.10 192.168.250.20 TCP iclcnet-locate > nfs [ACK] Seq=1185 Ack=889 Win=4163 Len=0 TSV=769821 TSER=432716 1091 24.924188 192.168.250.10 192.168.250.20 RPC Continuation 1092 24.924210 192.168.250.10 192.168.250.20 RPC Continuation 1093 24.924216 192.168.250.10 192.168.250.20 RPC Continuation 1094 24.924225 192.168.250.10 192.168.250.20 RPC Continuation 1095 24.924555 192.168.250.20 192.168.250.10 TCP nfs > iclcnet_svinfo [ACK] Seq=6893 Ack=1118613 Win=32625 Len=0 TSV=432892 TSER=769986 1096 24.924626 192.168.250.10 192.168.250.20 RPC Continuation 1097 24.924635 192.168.250.10 192.168.250.20 RPC Continuation 1098 24.924643 192.168.250.10 192.168.250.20 RPC Continuation 1099 24.924649 192.168.250.10 192.168.250.20 RPC Continuation 1100 24.924653 192.168.250.10 192.168.250.20 RPC Continuation 2nd Update 2011-07-06: There seems to be some influence from TCP window sizes. I was not able to reproduce this problem using FreeNAS (based on FreeBSD) as a NFS server. The wireshark captures showed TCP window updates to 29127 bytes in regular intervals. I did not see them with OpenIndiana, which uses larger window sizes by default. I can no longer reproduce this problem if I set the following options in OpenIndiana and restart the NFS server: ndd -set /dev/tcp tcp_recv_hiwat 8192 # default is 128000 ndd -set /dev/tcp tcp_max_buf 1048575 # default is 1048576 But this kills performance: Writing from /dev/zero to a file with dd_rescue goes from 170MB/s to 80MB/s. Update 2011-07-07: I've uploaded this tcpdump capture (can be analyzed with wireshark). In this case 192.168.250.2 is the NFS server (OpenIndiana b148) and 192.168.250.10 is the ESXi host. Things I've tested during this capture: Started "ioping -w 5 -i 0.2 ." at time 30, 5 second hang in setup, completed at time 40. Started "ioping -w 5 -i 0.2 ." at time 60, 5 second hang in setup, completed at time 70. Started "fsync-tester" at time 90, with the following output, stopped at time 120: fsync time: 0.0248 fsync time: 5.0197 fsync time: 5.0287 fsync time: 5.0242 fsync time: 5.0225 fsync time: 0.0209 2nd Update 2011-07-07: Tested another NFS server VM, this time NexentaStor 3.0.5 community edition: Shows the same problems. Update 2011-07-31: I can also reproduce this problem on the new ESXi build 4.1.0.433742.

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