LAVA 1.0 Content

QUOTE (Yen @ Jun 12 2008, 02:21 PM) Ok it look like a nice hack but I not able to get it working how to determine the pointer in bytestream Any idea Dany

QUOTE (AndyDm @ Jun 12 2008, 01:34 PM) I can't use IMAQ because i'm using a beta version of LabVIEW Dany

Some one knows about an activeX or dotNET control that can display images at a higher frame rate then the picture control. Currently I use the picture control to display 2d array of RGB value (32bits) as fast as I can, but I use Flatten Pixmap.vi and it takes 30ms to process my 640x480 image and it take a lot of CPU time. Is there other way to do this? Thanks Dany

I don't understand the langauge usd in the music. The video aws well done. Like the the movie "Brazil", after viewing it multiple times I came away wondering "What was that all about?" I liked the shadow of of the grim reaper with head on the skull (about 2:30 into it, using a shadow to fore-shadow) as well as the whale swimming bewteen alternating trees. If pressed I would have to say its the story of two friends that have taken two seperate paths. One to short term pleasure followed by enternal flight from a whale dispatched by an under-wear clad congregation. The other took the less pleasing path that ultimatly culminated in his death and resurection. The signifigance of the donkey still evades me. It was an asset in much of the journey but could not carry him the final miles, although it was there to great the resurected. Now it is my turn! What do the words say? How did you find it? What do you think? "tag" you are it! Ben

QUOTE (Aristos Queue @ Jun 11 2008, 03:49 PM) I can't express in words how happy I am to read your reply. There are tears welling up in my eyes because I am actually starting to "get it"! Maybe this emoticon will help illustrate. http://lavag.org/old_files/monthly_06_2008/post-29-1213214149.gif' target="_blank"> Thank you, Thank you, Thank you! Ben

QUOTE (Omar Mussa @ Jun 11 2008, 11:19 AM) Thanks Omar, I can see how that can be used if I can create my object at the start then fork the wire to feed two loops. In my case, objects will be coming and going. In the end I think I will end up with at least three parallel threads running, one for each of; 1) read from real-world source and update each object with a new value 2) Keep screen updating at 10 Hz 3) GUI, user can add new or toss old objects. Also can change attributes of any widget. I am attaching a zip of what I have so far (warning memory leak is due to how I implemented the re-drawing. Will fix this latter). This is what I have so far. My top level VI has two loops, 1) Screen updates, and 2) Handle "mouse down" events to add new widgets. The screen updates use the AE to invoke "Update Image" methods and widget that have a new image get re-drawn then picture is updated. When a mouse down event fires a new widget is added to the collection inside the AE and a the Image Change flag is set true. So I am still wondering if I am going the wrong way with this. Ben

QUOTE (crelf @ Jun 10 2008, 08:33 PM) "SHIBBOLETH" It took me a couple of minutes to remember were I heard that word before. It was the Old Testament version of a sign I spotted in a Simpson episode that read; "Noone who uses the word NUCULAR permitted beyond this point." Ben

I want to be able to update a picture control that represent a set of objects using a "update" method in one loop while handling user events for those same objects in another loop. I slapped together an action engine that uses a SR to store an array of the objects and then added actions that corespond to the methods. So far it seems to work fine but I have to ask; "Am I defeating the purpose and intent of LVOOP by using an Action Engine to store the LVOOP objects?" I ask because I have often read LVOOP as being an alternative to AE's and am concerned I am failing to get the whole LVOOP idea and am "just putting lipstick on a pig". Your thoughts? Ben

QUOTE (crelf @ Jun 11 2008, 03:30 PM) Some cleaning over the week-end and off we go ! QUOTE (neB) Don't hold your breath. Those kind of things only get developed in my spare time and between re-modeling of my rental property, plus a modular home my son is purchasing, along with car maitenance, I will not be dropping any nodes for that project until well after the snow starts to fly. Ohh, ok... Then I hope you'll have time to participate in the improvement/developpement when it starts

QUOTE (Antoine @ Jun 11 2008, 09:18 AM) Don't hold your breath. Those kind of things only get developed in my spare time and between re-modeling of my rental property, plus a modular home my son is purchasing, along with car maitenance, I will not be dropping any nodes for that project until well after the snow starts to fly. Ben

QUOTE (neB @ Jun 11 2008, 03:02 PM) With the aim of sharing it on LAVA's Code Repository ? QUOTE (neB @ Jun 11 2008, 03:02 PM) Dr. Gray's article on Managing Large Data Sets would be incorporated in to same. Thanks for the link to this article. Interesting code attached !! I haven't been that far

QUOTE (Antoine @ Jun 11 2008, 02:21 AM) A high capacity chart/graph and tables are on my list of XControls to write. Dr. Gray's article on http://zone.ni.com/devzone/cda/tut/p/id/3625' target="_blank">Managing Large Data Sets would be incorporated in to same. Ben

QUOTE (FLAnatic @ Jun 10 2008, 08:21 PM) Wow... 90, well done ! I've got 20 (all in LabVIEW since it is the only language I know) at the moment but I won't stay here, it's great fun !

QUOTE (crelf @ Jun 11 2008, 02:38 AM) LOL QUOTE (crelf @ Jun 11 2008, 02:38 AM) Sounds like a job for an xcontrol. It really does, I've been working on a set of VIs to efficiently -well as efficiently as I could- manage large data sets to be displayed on a graph. I'll share what I came up with. I guess the amount of work to wrap this into an xcontrol is not huge.. I was concidering putting a OpenG package request on this, and share my code as a starting point. Has anyone been working on this too ?

QUOTE (Eugen Graf @ Jun 10 2008, 11:06 PM) Hi, I don't really know how graph memory is handled but anway my best advice is : do not put 800k values, just put about 5-10 values per pixel (-> check the graph area size). I've saved a lot of memory with this technique. Hope this can help.

QUOTE (Eugen Graf @ Jun 10 2008, 09:44 AM) Too many issues for me to address all durring a break! For tables makes sure you are using LV 8.5 or above. Older versions had slower tables. "Defer FP updates" before updating tables usally helps. Action Enginces are great for situations were the same large set of data is accessed in different ways for different functions. Just make sure you "work in-place" as much as possible. have fun! Ben

QUOTE (Aristos Queue @ Jun 9 2008, 06:56 PM) Thanks in advance* for that reply! I am working my way through all of the documentation I could find on LVOOP. The above question came up as I was moving from page 3 to page 4 of the http://zone.ni.com/reference/en-XX/help/371361D-01/lvconcepts/creating_classes/' target="_blank">Creating LabVIEW Classes article. The LAVA Wiki articles are next in my stack of print-outs. Ben * Thanks in advance since it will take me some time to fully conceptualize the reply.

Hi Eugen, You are trying hard so let me help out a little. In this link you will find my collection of "LabVIEW_Performance" tags. You will find a lot of postings by Greg McKaskle in that list since I am working my way through the forum chronologically. One of those links (this one) has been called teh "Clear as mud" thread but it illustrates what Aristos Queue was talking about. Ben

QUOTE (tcplomp @ Jun 10 2008, 12:07 AM) They bear a strong resemblence to ones and zeros floating randomly off into that big bit bucket in the sky. Sea Story Time: (I don't think I have shared this one on LAVA yet) I used to work as district support for DEC specializing in large disk drives. After spending an evening working with a customer to recover (well sorta) from a disk crash, one of the engineers described his adventures as follows; " After rebuilding the drive and running diagonstics the drive looked OK. So we put the customers backup pack in the drive and it mounted fine. We were standing behind the disk drive cabinet and we noticed what looked like a cloud of fine brown dust coming out of the back of the drive. The customer looked at me and asked "What is that?" I replied, "Data". " Story orignally told by Bill Thomas of Digital Equipment Corporation. Ben

QUOTE (TobyD @ Jun 9 2008, 10:59 PM) I did ask for it, but I didn't receive the mail form the admin :thumbdown:

Altough I can not prove it, I believe VI's are better the second time I write them. Ben

QUOTE (Omar Mussa @ Jun 9 2008, 03:46 PM) Thank you Omar! OK I'll trust you on it being expected. Now I I have to do is figure what ancestors are and and what override means. Ben PS: please excuse my dumb questions on LVOOP. I have been reading and I'm trying but OO is still a forign language. Learning the machine instruction set of a KL-10 seems easy to getting this old hardware guys head around the terminology.

Why does changing the scope of a VI within a class to "private" break the class? In the attached zip you will find a folder complete with project and required files. I started by defining a generic class and then create accessor (?) for all of the values in the class. Whenever I set any of the VI within that class scope to "private" the class breaks (they all dynamic). So how do I set a accessor(?) as private? Not knowing LVOOP I was guessing that I keep everything private and only make protected or public what I absolutely needs to expose. I have to admit I am a complete loss as to what I am doing wrong. [Edit] Are there rules about dynamic dispatch and private not going together? [Edit again] After creating a new project blah blah blah, I manually set connectors as required and issue went away. So private and dynamic do not mix. I am not sure exactly what dynamic really means (I thought it was a way to let LV choose a polymorphic instance at run time) but I am not sure what that has to do with breaking when it is made private. Ben feeling very LVOOP stupid at this point.

QUOTE (Aristos Queue @ Jun 9 2008, 11:25 AM) But not all branches are data copies. Ex: Get array size (does not mod data) can be scheduled before array is used. Ben

QUOTE (ragglefrock @ Jun 9 2008, 11:08 AM) Notes on how I got the queue to fail in LV 6.1 The VI that created the queue was a top level VI that was only loaded into memory when the Windows machine opened it. The top level VI was an action engine where the first action was "Init" creating the queue". Latter calls invoked other actions including reading from the queue. When the ref to the top (crator) went invalid due to network timeout, the queue went invalid. At least that is what my memory tells me. Ben