Nested LINQ Aggregate queries vs Nested Foreach statements example

At Trafilm project’s Metadata (http://github.com/zoomicon/Trafilm.Metadata) I have a linked data structure where a Film contains multiple Conversations which contain multiple L3STinstances, which in turn contain multiple L3TTinstances.

I had the need to calculate a list of all unique L2language values of L3TTinstance grand-grand-children for a Film (to keep as calculated metadata for display at the Films PivotViewer collection available at http://gallery.trafilm.net/collection/films.cxml (that is a Collection XML file), which you can explore via HTML5 PivotViewer (seajax) at http://gallery.trafilm.net/film).

BTW, other objects mentioned have their own separate PivotViewer galleries (shown at http://gallery.trafilm.net/conversation, http://gallery.trafilm.net/L3STinstance, http://gallery.trafilm.net/L3TTinstance respectively). Note that the metadata for the respective collections is still being populated at the time of writing, but some sample data is included to try out.

 

Initially I did it with nested LINQ Aggregate expressions:

L2dubbedLanguages = value.Aggregate(new List<string>(), (total, conversation) =>

  (conversation == null) ? total :

              conversation.L3STinstances.Aggregate(total, (totalST, l3STinstance) =>

     (l3STinstance == null) ? totalST :

           l3STinstance.L3TTinstances.Aggregate(total, (totalTT, l3TTinstance) =>

       {

          if ( (l3TTinstance != null) &&

               !string.IsNullOrEmpty(l3TTinstance.L2language) &&

               (l3TTinstance.L2mode == "Dubbed") &&

               !totalTT.Contains(l3TTinstance.L2language) )

            totalTT.Add(l3TTinstance.L2language);

          return totalTT; //note that totalTT == totalST == total

       }

  ))).ToArray();

 

However, since I also had to repeat again all the code block shown above for the “Subtitled” L2languages (just replacing the “Dubbed” string comparison in it), it was more optimal to combine the two in one code block using nested foreach statements that host one switch statement:

//Calculated from Conversations.L3STinstances.L3TTinstances//

IList<string> dubbed = new List<string>();
IList<string> subtitled = new List<string>();
foreach (Conversation conversation in value)
  if ((conversation != null) && (conversation.L3STinstances != null))
    foreach (L3STinstance l3STinstance in conversation.L3STinstances)
      if ((l3STinstance != null) && (l3STinstance.L3TTinstances != null))
        foreach (L3TTinstance l3TTinstance in l3STinstance.L3TTinstances)
          if (l3TTinstance != null)
          {
            string l2language = l3TTinstance.L2language;
            if (!string.IsNullOrEmpty(l2language))
              switch (l3TTinstance.L2mode)
              {
                case "Dubbed":
                  if (!dubbed.Contains(l2language))
                    dubbed.Add(l2language);
                  break;
                case "Subtitled":
                  if (!subtitled.Contains(l2language))
                    subtitled.Add(language);
                  break;
              }
          }
L2dubbedLanguages = dubbed.ToArray();
L2subtitledLanguages = subtitled.ToArray();

 

Having done this refactoring, I decided to also change some of the Conversation object’s calculated fields with a LINQ Aggregate:

L3STlanguages = value.Aggregate(new List<string>(),
  (total, l3STinstance) => { 
     if ((next != null) && 
         !string.IsNullOrEmpty(l3STinstance.L3STlanguage) && 
         !total.Contains(l3STinstance.L3STlanguage)) 
       total.Add(l3STinstance.L3STlanguage);
     return total;
}).ToArray();

and which had to be repeated again for the L3STlanguageType field (that is by just changing L3STlanguage to L3STlanguageType in the code block above), to the following nested foreach statements’ code block:

IList<string> languages = new List<string>();
IList<string> languageTypes = new List<string>();
foreach(L3STinstance l3STinstance in L3STinstances)
  if (l3STinstance != null)
  {
    string language = l3STinstance.L3STlanguage;
    if (!string.IsNullOrEmpty(language) &&
        !languages.Contains(language))
      languages.Add(language);

    string languageType = l3STinstance.L3STlanguageType;
    if (!string.IsNullOrEmpty(languageType) &&
        !languageTypes.Contains(languageType))
      languageTypes.Add(languageType);
  }
L3STlanguages = languages.ToArray();
L3STlanguageTypes = languageTypes.ToArray();

That should also avoid any intermediate memory objects overhead that comes with usage of LINQ for Aggregation.

HowTo: use PivotViewer in WPF

PivotViewer is an impressive Silverlight control (see my usage at http://gallery.clipflair.net), however Microsoft never released it for WPF.

One could work arround this by embedding Silverlight in their WPF app using the WebBrowser control and talking to it via the JavaScript Bridge of Silverlight, however they could also embed one of those HTML5 PivotViewer-compatible controls that have surfaced in recent years.

Apart from LobsterPot’s HTML5 PivotViewer and its older free version, for another HTML5 PivotViewer (and also a DeepZoom implementation for HTML5) you could host that comes from former SeaDragon team members at Microsoft and seems to work very well see:

http://seajax.github.io/

https://github.com/seajax/seajax/tree/master/v2/app/pivot

https://github.com/seajax/seajax/blob/master/v2/app/pivot/quickstart.html

https://github.com/seajax/seajax

Note that the WebBrowser control uses IE7 or something as HTML engine by default and you need some meta markup at the top of your HTML to tell it to use Edge mode – the latest IE engine that is installed)

<meta http-equiv="X-UA-Compatible" content="IE=edge">

PivotViewer for a rich search experience

For ClipFlair, I’m looking into implementing advanced search using Silverlight PivotViewer

Update: 

You can now check out ClipFlair Gallery in all its PivotViewer with DeepZoom glory.

A really nice example of PivotViewer search is at:

http://www.appletoncompassion.org/VirtualExhibitViewer

This may take long time to load, since its loading 10000 children art DeepZoom image tiles

You can use the mousewheel to zoom in there or the zoom slider at top-right (can also click an item to zoom to it)

See the filters at the left handside, play with them by selecting items there at the various properties to see the images get rearranged to show only ones selected by the filters.

Has also buttons at the top-right to bin the items based on having same values at properties selected

Another good example is Netflix movie catalog:
http://netflixpivot.cloudapp.net/
e.g. select Sort: Genre at top-right and click Graph View button there instead of the default Grid View to see the items get binned by Genre, then start filtering them down from the left handside bar

Also see a SharePoint sites collection search with PivotViewr:
http://www.wssdemo.com/livepivot/

MSDN magazine collection with PivotViewer:
http://pivot.blob.core.windows.net/msdn-magazine/msdnmagazinepivot.htm

Finally, for a nice series of Silverlight PivotViewer programming articles by Tony Champion see:

http://tonychampion.azurewebsites.net/blog/index.php/tag/pivotviewer/

http://pivotviewerlessons.codeplex.com/ (source code)

http://pivotviewer.championds.com/ (live examples)

BTW, people are also working on HTML5 PivotViewer:

http://www.rogernoble.com/2012/02/02/addressing-the-elephant-in-the-room-the-html5-pivotviewer/

http://lobsterpot.com.au/lobsterpot-html5-pivotviewer-now-open-source

http://lobsterpothtml5pv.codeplex.com/

http://lobsterpot.com.au/pivotviewer/api-reference

http://lobsterpot.com.au/pivotviewer/extending-the-html5-pivotviewer

http://pivot.lobsterpot.com.au/html5.htm (Live HTML5 Sample)

http://examples.hubbardone.com/html5/html5pivotviewer.htm (Live HTML5 Sample)

For developers, here are some direct links to .CXML (Collection XML) files:

http://gallery.clipflair.net/collection/activities.cxml
http://gallery.clipflair.net/collection/video.cxml
http://gallery.clipflair.net/collection/images.cxml

http://pivot.blob.core.windows.net/msdn-magazine/msdnmagazine.cxml
http://images.appletoncompassion.org/deepzoomfull/AppletonCompassionFull.cxml
http://www.esrc.ac.uk/Pivot/CXML/Grants/Grants.cxml
http://labs.championds.com/MIX10/MIX10Collection.cxml
http://spscollection.blob.core.windows.net/pivot/SharePoint.cxml
http://www.xpert360.net/SQLBits/Collection.cxml
http://pivot.metia.com/worldcup/wc2010-dz.cxml

By opening the .CXML file URL in a web browser you can see its XML-based structure.

By using ClipFlair Studio‘s Gallery component you can open most of those .CXML URLs and play with the respective collection (you use the wrench button on the Gallery component’s titlebar to turn it over and set the Source URL, then turn over again to see the collection – just wait a bit if it’s big and takes some time to load).  An alternative is to open in your browser a URL of the form http://studio.clipflair.net?gallery=http://spscollection.blob.core.windows.net/pivot/SharePoint.cxml

Not all of these URLs will work in ClipFlair Studio’s Gallery component though, because some servers may be using restrictive access policy files for Silverlight, not allowing a Silverlight app like ClipFlair Studio which is served from http://studio.clipflair.net to download the .CXML file.

HowTo: Check your web browser and plugins for needed updates

Qualys BrowserCheck will perform a security analysis of your browser and its plugins to identify any security issues. You can install it at https://browsercheck.qualys.com/

 

Another useful quick online tool (needs no installation) for checking that you do have the latest in web browser technology is Browse Happy, at http://www.BrowseHappy.com

Try IE9 with HTML5 showcases from Microsoft, Mozilla, Google and Apple

Since IE9 final version is being released today (http://www.beautyoftheweb.com), here are some HTML5 showcases from different browser makers to test it out against:

• Microsoft: http://ie.microsoft.com/testdrive
• Mozilla: https://demos.mozilla.org/en-US
• Google: http://www.html5rocks.com / http://studio.html5rocks.com
• Apple: http://www.apple.com/html5

Could even try some of Google’s Chrome specific demos in case they work with IE9 too: http://www.chromeexperiments.com/

 

IE9 RC (Release Candidate) wasn’t fully HTML5 compliant last time tested mind you, but neither the other browsers were as you can see at W3C tests:

http://test.w3.org/html/tests/reporting/report.htm

http://www.w3.org/html/wg/wiki/Testing

IE9 is way better though than IE8: http://samples.msdn.microsoft.com/ietestcenter/

Can also see lots of HTML5 tests for browsers at: http://html5demos.com/

 

BTW, it is very interesting that IE9 also supports the WOFF format (Web Open Font Format). Typeface lovers can drool freely here: http://lostworldsfairs.com/

 

Here’s a relevant post with nice video of Mozilla’s showcase: http://techtimely.wordpress.com/2011/03/08/html5-showcase-demos/

 

So should we start drooling on future WebGL support in the browsers’ world too now?

http://techtimely.wordpress.com/2011/03/04/webgl-1-0-specification-releasedwebcl-coming/

(see video at that post and find more WebGL apps at http://learningwebgl.com/blog/)