Why are variants sometimes better to use than clusters?

I am using variants in a driver I am developing to avoid having to pass a ton of wires between subVIs. My mentor asked me why I was doing this. He wanted to know why I wasn't just using clusters. The only answer I could come up with was that is was convenient to be able to "dereference" (I'm not sure if this is the correct term) the variant for attributes with the Get Variant Attribute VI and a string associated with the attribute of interest. Are there any other advantages of using variants?

Yes! Variants are great when you are trying to write code that must operate on many different data types. However there are caveats that make error handling more difficult and critical. Take a look at the OpenG LabVIEW Data Tools, which make Varaint usage practical. This library is part of the OpenG Toolkit.
LabVIEW Data Tools Presentation - variants, run-time type checking, and data manipulation design patterns
Examples:
Get Object Attributes as XML
<
A HREF=http://www.openg.org/tiki/tiki-index.php?page=EXAMPLE%20-%20OpenG%20Flatten%20to%20XML>OpenG Flatten to XML
Python Client to LabVIEW Server
Universal Probe

Similar Messages

Why are hp servers general more expensive than dell offerings ?

Because that's where they feel the price point is in the market for their servers.

why are hp servers general more expensive than dell offerings ?
This topic first appeared in the Spiceworks Community

What programs are better to use than iChat for video conferencing?

Please help I keep using iChat and it never works any more. What is better to use? Just name some so I can video conference. Thank you for your help

Hi,
Scroll this section fro items 5 through 12
http://www.ralphjohns.co.uk/page5.html#_other
Also this page http://www.ralphjohns.co.uk/EZJim/EZJimpage7.html for APps in general.
9:51 PM Wednesday; January 27, 2010
Please, if posting Logs, do not post any Log info after the line "Binary Images for iChat"

Why are two queries better than one

I'm trying to help out our developers who are struggling with the performance of a very simple select statmenent that for some reason is exhibiting some very inexplicable results.
I'll show the SQL as a single statement first.....
select * from transaction1 t where t.hid in (select distinct h.hid from history1 h,filter1 f where h.fid = f.fid and f.match='value');
transaction 1 has 250k records, history1 has about 100k as does filter1. We know generally the subselect will only return a total of half a dozen or less records (only 1 in our testing here).
Running the above query takes around 7 seconds.
Changing this to a with clause.....
WITH a as (select distinct h.hid from history1 h,filter1 f where h.fid = f.fid and f.match='value') select * from transaction1 t where t,hid in (select a.hid from a);
and the runtime drops to 3 seconds. But then re-running the first statement again also now takes 3 seconds (so I guess there's some caching going on there).
Now what really puzzles is if we split this into two queries.....
select distinct h.hid from history1 h,filter1 f where h.fid = f.fid and f.match='value';
This takes .1 of a second,
select * from transaction1 t where t.hid in (12345);
And this takes .1 of a second.
So why when run seperately are they so fast, yet combined they take so long. I'm a bit baffled by this. We've rewritten the same SQL in half a dozen different ways with the same result and also done the same thing with other tables as well. Is it an optimisation issue?

Appologies for not following protocol, my first time posting on here.
Oracle 10g clustered.
We have limited access as it's a customers server, but the explain plan comes back as....
PLAN_TABLE_OUTPUT
Plan hash value: 898894568
| Id | Operation            | Name              | Rows | Bytes | Cost (%CPU)|Time     |
PLAN_TABLE_OUTPUT
|   0 | SELECT STATEMENT     |                   | 49553 |    37M| 7075   (2)|00:01:25 |
|* 1 | HASH JOIN RIGHT SEMI|                   | 49553 |    37M| 7075   (2)|00:01:25 |
|   2 |   VIEW               | VW_NSO_1          | 26131 |   331K|   476   (4)|00:00:06 |
|* 3 |    HASH JOIN         |                   | 26131 |   791K|   476   (4)|00:00:06 |
PLAN_TABLE_OUTPUT
|* 4 |     TABLE ACCESS FULL| FILTER1           | 26131 |   484K|   246   (4)|00:00:03 |
|   5 |     TABLE ACCESS FULL| HISTORY1          |   104K| 1225K|   227   (3)|00:00:03 |
|   6 |   TABLE ACCESS FULL | TRANSACTION1      |   199K|   150M| 6593   (1)|00:01:20 |
PLAN_TABLE_OUTPUT
Predicate Information (identified by operation id):
   1 - access("T"."TID"="$nso_col_1")
   3 - access("H"."HID"="F"."ID")
   4 - filter("F"."MATCH"='value')
20 rows selectedI'll admit, I'm not completely clear on what I'm reading here, other than the fact there are some big differences in the timing values
We don't have privaleges to run trace, so I'm a bit stuffed there as I'm on the clients site, however I will get my developers to try this on our local server.
Edited by: user1410957 on 15-Sep-2009 06:14

Why are Ipod Apps better than Iphone Apps?

There are some really nice apps available to the ipod touch that aren't available to the Iphone. Go search Ipod apps in the Itunes store and you will see what I am talking about. How come the same apps aren't available for both devices?

oops, they are not on the touch they are for the nano, and reg ipod. Still I am sure there is a way to develope them for the iphone.

Why are SMB connections so much slower than AFP on my Mac Servers?

I work in a school with a mix of Mac and PC clients and servers. My Mac servers all serve out file sharing to both AFP and SMB. When my Mac clients connect to the Mac servers via SMB, it takes several seconds, sometimes up to a minute before the login screen appears. When I connect via AFP, the login window appears instantaneously. I have also noticed that when the Macs connect to Windows servers, which are obviously SMB, the same long delay occurs. It's manageable, but because it's so quick with AFP, I wonder why the delay?
My biggest concern is that Yosemite connects via SMB by default. Right now everyone is running Mavericks, which will still assume you're asking it to connect via AFP when you don't specify the afp:// in the address. My Yosemite beta machine does the opposite, it assumes SMB when the address doesn't specify. When all my clients make the switch next year, I'm expecting much longer than usual connection times for my mac users who are not technically inclined and who are used to just typing a word or phrase in the "Connect to:" dialog box, rather than an actual address (such as afp://server, they would currently just type "server" and it fills in the rest for them).
Thanks for any help with this. I would love to find out how to speed up the SMB connections.

Performance Tuning the Network Stack
SMB server browsing woefully slow
mac os x slow copy file from Samba Server
Fix slow network file transfers across Mac OSX Lion

Why are shapes so difficult to use now?

I cant see a single way shapes in CC are better. All extra stages and annoyances, anyone have better workflow method to combat these new things?
1. Cant duplicate easily.
Before: select layer, cmd + j = duplicated
Now: select layer, cmd + j = blank layer, nothing.
Solution, select the pen, select the shape, select the layer, NOW duplicate.
Am I doing it wrong? Because before you could just duplicate, now you have to have the shape selected and the layer. This is very frustrating adding extra clicking/selection to my workflow.
If you right click a shape and duplicate, it works. So the shortcut of duplicate doesnt work the same?
2. Pen Points are infuritating.
Before: drag a box out to select multiple points on a shape.
Now: drag a box out, selects every point in the entire document on every layer. How is this better than before?
Solution, none really? If there is one I take it, its an extra click.
3. A shape remembers the last point you click. Great so now everytime I click a shape I have to deselect that point, and usually try to do that using a drag box, which doesnt work.
I just dont see how any extra workflow helps bring anything good to photoshop. What are the benefits to this new system?

I have bought a Ipad 4 a week ago and find it is like wading though treacle to get my data loaded! Itunes seems very unintuitive and difficult to use. I managed to transfer my music and films over from my PC and started using them on the Ipad when suddenley they dissappeared! "No Content" so I had to go back and reload them all again. I still have not found a way to transfer and use my documents onto the Ipad. I have an Android tablet and that is so simple to use(and a liot less expensive to buy). Why can't I access the file system on the Ipad, this seems to be the heart of my problems. I am not inexeperienced with computers as I am a retired Computer Manager/Analyst/[programmer over 20 years.

Why are my .avi files extracted using PE3 only playing audio when using Windows Media Player?

I extracted a lot of my old movies using PE3 that came from my 8MM camera. They played fine on XP.
I now have Windows7 64 bit and when I play them in Windows Media Player, they only play the sound.
I'm guessing that this is a codec issue.
Should I re-extract them using a different product that uses a more standard codec?
Thanks!

It depends on your workflow. So we'll need more details.
How did you digitize the video from your 8mm camcorder? Many devices capture as AVIs, but do so while using codecs that aren't universally playable. Also, do make sure you've got the latest version of Quicktime on your new computer. It can add some important video functionality to your computer.
You say you used Premiere Elements to "extract" your movie. How did you do this? Did you use a device like the ADS Pyro AV Link or Grass Valley Canopus AVDC?
Finally, are you trying to play the raw files or did you create a project with them in Premiere Elements and then Export/Share your video? And, if the latter, which output settings did you choose?
Meantime, try downloading VLC Player to your new computer and see if it can play the files. It is a much better player than Windows Media Player (or Quicktime Player, for that matter). And let us know yoru results.
As I've said, the more details you can give us, the more likely we can help you.

Why are the compiled SWF colors brighter than in Flash CC while programming

Just a quick question, when I open the SWF with FlashPlayer the colors are brighter than in Flash CC while programming, why is that?
Left part is in Flash CC right side is the compiled SWF opened with FlashPlayer.

Flash uses the sRGB color space. If your original art was created using a different color space then the colors will look shifted.
This article may help: http://www.adobe.com/devnet/flash/quickstart/color_correction_as3.html

Why Mac pro is better & more expensive than IMac?!

can you advice me on this:
tell me which one is more practical and powerful for 3D rendering and animation?! why?!
and why Mac pro is more expensive than IMac?! even though numbers in IMac are higher than Mac pro.......
IMac:
          - 27-inch
          - 3.4GHz Quad-Core Intel Core i7
          - 16GB 1333MHz DDR3 SDRAM - 4x4GB
          - 2TB Serial ATA Drive
          - AMD Radeon HD 6970M 2GB GDDR5
or
Mac pro:
Two 2.66GHz 6-Core Intel Xeon “Westmere” (12 cores)
12GB (6X2GB)
2TB 7200-rpm Serial ATA 3Gb/s hard drive
2TB 7200-rpm Serial ATA 3Gb/s hard drive
ATI Radeon HD 5870 1GB
One 18x SuperDrive

Apparently you don't fathom or realize what I said:
Better value: Mac Pro 6-core 3.33GHz. You can buy base and throw in W3680.
You can buy a single 6-core like that from Apple and pay $900 more.
I do not recommend 12-core.
I do not recommend the slower 2.66 processor
I do recommend avoiding the 2009 model.
Better off starting with the 2.8 4-core and go from there.
Ivy Bridge socket LGA2011 will have a lot of other features making them the "to die for" but no one knows and I for one would not want to be on cutting edge with any chipset or new revision. Seriously, Apple has always had issues with first silicon whether 2011 MBP or iMac or 2008/2009 Mac Pro. And always takes a couple OS updates. And then things break. And then software has to catch up.
A slower 12-core is not going to future proof. It is going to cost more and not deliver.
For last year we've all been seeing and saying 6 x 3.33.
why I sent you link to MPG site.

Why are images displayed in Photoshop different than the same images displayed in Indesign?

My images imported to Indesign do NOT display as the images in Photoshop.
They seem to display under different color profiles.
The images in Indesign are more desaturated than the images in Photoshop.
This is a problem because now I don't know which image appearance to trust!
How can you get the Indesign images to look like the images in Photoshop?
I use Photoshop CS4 and Indesign CS3.
I import the images from Photoshop to Indesign for exporting to a PDF as the base for Blurb printing (www.blurb.com).
I use the CMYK profile Blurb_ICC_profile.icc:
The images in PS4 are converted to Blurb_ICC_Profile (CMYK).
Both in PS4 and ID3 the color settings are
                           Working spaces:
                              CMYK: Blurb_ICC_profile
                           Color management Policies:
                               CMYK: Preserve Embedded Profiles.
The images are imported into Indesign by drag and drop from Bridge CS4. In Bridge it says that the images have color profile CMYK, Blurb_ICC_profile.
I also do get "Unsynchronized: Your Creative Suite Applications are not synchronized for consistent color." And I don't seem to be able synchronize between CS3 and CS4, or whatever. I do NOT depend on any synchronization.
The settings above should be enough to show the images consistently in Photoshop and Indesign.
SO WHY DOES IT NOT?
Should not Adobes own applications be able to keep color consistency?

Hi WA Veghe,
>First: DO synchronize, makes sure you have the same profile settings and color mange settings.
I don't seem to be able to synchronize between CS4 (Photoshop) and CS3 (Indesign).
It seems I have to do without synchronizing..
>I do not seem to find HOW you are diplaying images on you screen: with Soft proofing?
What happens if you soft proof in Photoshop and InDesign on screen: View > Proof colors. Do you proof with the same profiles, both simulate paper and black on?
I can simulate Proof Colors (working CMYK), but not simulate Paper, both in Indesign and Photoshop.
Problem is: SAME settings in Photoshop and Indesign BUT the image displayed in Photoshop is brighter and more saturated.
So which image should I correct after?
thanks for all help
/L

Why are callbacks sometimes skipped?

Hi All,
BPEL 10.1.3.1
OS Linux
I have question about why an asynchronous BPEL process, called ServiciosRed, would report the following:
"Skipped callback "RespuestaSR" on partner "client"."
I understand that if this process had been called directly from a webpage/BPEL console, then this expected, but in this case this process is being called by another BPEL process residing in the same environment.
ServiciosRed supports multiple operations and is called several times by the parent as shown below:
Parent Flow
... (1)
<invoke name="SR_BajaAddons" partnerLink="ServiciosRed" portType="ns13:ServiciosRed" operation="Addons" inputVariable="SR_Addons_InputVariable"/>
<receive name="Respuesta_SR" partnerLink="ServiciosRed" portType="ns13:ServiciosRedCallback" operation="RespuestaSR" variable="Respuesta_SR_InputVariable"
createInstance="no"/>
... later on in the flow (2)
<invoke name="Migracion_KPN" partnerLink="ServiciosRed" portType="ns13:ServiciosRed" operation="Evolucion" inputVariable="Migracion_KPN_InputVariable"/>
<receive name="Respuesta_SR" partnerLink="ServiciosRed" portType="ns13:ServiciosRedCallback" operation="RespuestaSR" variable="Respuesta_SR_InputVariable"
createInstance="no"/>
... later on in the flow (3)
<invoke name="SR_AltaAddons" partnerLink="ServiciosRed" portType="ns13:ServiciosRed" operation="Addons" inputVariable="SR_Addons_InputVariable"/>
<receive name="Respuesta_SR" partnerLink="ServiciosRed" portType="ns13:ServiciosRedCallback" operation="RespuestaSR" variable="Respuesta_SR_InputVariable"
createInstance="no"/>
In (1) the parent receives the response.
In (2) the parent DOES NOT receive response - and I see the "Skipped callback..." message when I view the sub-flow
[I manually supplied the response using the interactions tab]
In (3) the parent receives the response.
What is causing the skipped behaviour? In the past I have simply created a new partner link for use @ (2) and the issue appears to go-away - But I shouldn't have to do this - right?
Thanks - Anit

Yes! Variants are great when you are trying to write code that must operate on many different data types. However there are caveats that make error handling more difficult and critical. Take a look at the OpenG LabVIEW Data Tools, which make Varaint usage practical. This library is part of the OpenG Toolkit.
LabVIEW Data Tools Presentation - variants, run-time type checking, and data manipulation design patterns
Examples:
Get Object Attributes as XML
<
A HREF=http://www.openg.org/tiki/tiki-index.php?page=EXAMPLE%20-%20OpenG%20Flatten%20to%20XML>OpenG Flatten to XML
Python Client to LabVIEW Server
Universal Probe

Why are swatches I'm not using 'merge' into my document?!?

Do color swatches 'stick' to an Illustrator file even after you delete them? I have to use the same spec box on all my documents to relay info to my printer which is in it's own Illustrator doc. BUT when I copy it and paste it into any file I am working on Illustrator always asks me about merging the swatches even tho there is only ONE color being used in my spec box file. HELP!!! My printer is losing patience b/c they think my files are a mess when I send them but my swatch pallet is clean and tidy on my end! Is there a way to clean up this mess??
Thanks!

Sticky Colors
There is a technical problem where swatches keep coming back, but you would see "deleted global color" as the swatch name. If your swatch palette is tidy and clean, then make a screen shot and attach that in an email to your printer, and ask them to return a screenshot showing the problem colors. Post the screenshot here and we can better help you.
Merge Swatches Notification
Does you clipboard and the document you are pasting into both contain the offending color? That error should only come up in that case and the colros haev the same name, btu a different color composition

Why are MediaPlayer callbacks all Runnables rather than EventHandlers?

Every other API in JavaFX with event processing callbacks implements EventTarget and allows EventHandlers to be registered to handle events.
However the MediaPlayer does not implement EventTarget and callbacks for things which look like they should be events (e.g. onPlaying, onStopped, onPaused) are handled by registering a Runnable.
Why is MediaPlayer different? Are there any extra considerations which need to be taken into account when programming the MediaPlayer?
For instance, in code such as this (from forum post How can I solve the error "media corruption error"? =>
mpLogo.setOnEndOfMedia(new Runnable() {
public void run() {
    mpLogo.stop();
    mediaView.setMediaPlayer(mpSaludo);
    mpSaludo.play();
    root.getChildren().remove(grupo2);
});Is the runnable always guaranteed to be run on the JavaFX Application thread? or should you wrap the code in a Platform.runLater call to ensure that the actions manipulating active scene graph objects taken on end of media only happen on the JavaFX Application thread?
mpLogo.setOnEndOfMedia(new Runnable() {
public void run() {
    Platform.runLater(new Runnable() {
      public void run() {
        mpLogo.stop();
        mediaView.setMediaPlayer(mpSaludo);
        mpSaludo.play();
        root.getChildren().remove(grupo2);
});

I don't know, I think this is an error. I know that there was one part of the media APIs that was called very frequently (the stuff related to histograms) that we didn't use events, but this most certainly should have been events. Dang. If I could find it in email history there must be something on it, but looking at it here I was both surprised and shocked that this one slipped through (since I don't know under what circumstance it would have made sense to use a Runnable here). In fact at first I thought maybe you were looking at some old code (before I knew it was you who posted).
OK, suppose we all agree this was an error and we need to fix this. What to do? We can deprecate all these methods, but the new methods we'd want to supply would then have the wrong names. We could introduce a proper Event subclass for this and also a special EventHandler which also implements Runnable, just so it can be reused here. We'd then deprecate the methods and just change the hierarchy when we JSR the thing?
I'm not sure how to recover, any other ideas?

Why are all my keyboard shortcuts using the "Alt" key instead of the "Ctrl" key? I'm using Windows 7 and Firefox 5.0.1.

I recently downloaded Firefox 5 and noticed that all my keyboard shortcuts default to using "Alt" key instead of the "Ctrl" key (so, for example, opening a new tab is Alt + T instead of Ctrl + T).
I noticed that this is even true for copying and pasting within Firefox (Alt + C and Alt + P are the only commands that work).
Any idea why this is happening? I am running Windows 7 and Firefox 5.0.1.

Thanks, eveostay! That worked. (And for the record, what a crazy user agent string...)

Why are variants sometimes better to use than clusters?

Similar Messages

Maybe you are looking for