Francois Normandin

QUOTE (miab2234 @ Nov 23 2008, 03:30 PM)

It do but the 2. Problem is it stops at 2. LED.But i want that it continous.How can i do that ?

First, you should make sure that the comparison (equal) is not always TRUE.

In your code, the while loop will always stop after one iteration because you initialize the shift register to 1 and check if it's equal to 1. Of course, it will always output TRUE and stop your loop.

To run continuously until you say so, use a stop button. (wired to

http://lavag.org/old_files/monthly_11_2008/post-10515-1227479540.png' target="_blank">

-- OUPS, too late

QUOTE (MikaelH @ Nov 23 2008, 04:09 PM)

I use Class Attributes from time to time.

The definition if of cause that this data is shared between all objects of the same type.

If you e.g. have a common TCP/IP server all objects should communicate with, it's good to save the IP-address here.

If you need to change the IP-address in the middle of the execution you just change it in one place instead of changing all objects.

That's a good point indeed. I had thought only of invariant properties, but this is a good peeble... since I'm also working on a TCP client-server!

QUOTE (MikaelH @ Nov 23 2008, 04:09 PM)

That's exactly the answer I was looking for. Not only was I wondering what would happen if I changed inheritance or created new related classes, but I see there are two possible implementations based on how I really want to share information between the objects. And that's a trick that will hopefully keep me from running in the wall when I try to design it.

thanks Mikael.

QUOTE (TG @ Nov 23 2008, 02:25 PM)

Sounds a lot like me!

Well now that I know of the TCPIP address example, I'll try to find other ways to make use of them.

QUOTE (miab2234 @ Nov 23 2008, 02:44 PM)

1.In my programm it shows only 1D array.(Actually i need 2D array.It can be squre)

Right-click on the index of your array and select "Add Dimension". That will convert your 1D Array to 2D.

Thanks Omar, :thumbup:

I think I have something similar. (I have a server that ran for three months non-stop and I got to 1.5GB virtual memory usage... pretty sluggish)

I'm almost sure I check for a semaphore with "Not a refnum".

I've got a theoretical question on GOOP Classes.

I'm usually defining my object attributes for anything that could be different from one object to the other (ID, init parameters, position, speed, etc.) and, as I understand it, the class attributes are for everything that is class invariant (let's say supply voltage, material, dimensions, etc.). But I usually never use the class attributes and put all the fixed parameters in the object attributes, initialize them once with "Object_Create" and never change them in the course of my program. I think it's not optimal design but it works rather simply and it's more readable for colleagues less familiar with OOP.

I would like to know if it is good practice to simply ignore the class attributes? My concern is as to what would happen if in the future I were to create a sister-class and make these two classes inherit from a parent. Those sister classes will have different class attributes... How well does it scale up? Will I run into a wall one way or the other? Any comments?

thanks,

Francois.

QUOTE (jives @ Nov 20 2008, 03:04 PM)

Hello!

Is there any way to automatically disable or enable specific LV code when building an application? Maybe with a conditional disable structure, or something like that.

This would come in very handy, for example when using a relative path which changes when running code as an application or in the LV development environment. Or one could hide debug output which is useful in the LV environment, but not in a standalone application.

Any help is greatly appreciated!

You could use conditional disable structure, but only to discriminate between CPUs, OS, Targets (Win, Mac, Linux, UNIX)... If you want to have a difference between Development System and RunTime Environment, you'll need to use Application.Kind Property Node and use cases in your code. I know there are threads asking for this specific differentiation in the App Builder, but I'm not sure there is anything available as of now. It's recurring so I wouldn't be surprised if NI worked on that for a future release. :2cents:

http://lavag.org/old_files/monthly_11_2008/post-10515-1227212796.png' target="_blank">

QUOTE (Yair @ Nov 20 2008, 02:35 PM)

Another alternative is simply to create a 1D array of clusters, where the first cluster element would be a string and the other two would be numerics. You can make the third an "indicator" by changing its enabled state to disabled (1). You won't be able to get it to look exactly like the table, but you can get pretty close by coloring things transparent.

That's a real good way to do it. I hadn't thought of that. The use of "disabled" for the indicator makes it easy without the need to make it an XControl. (which would be sharp too...)

Download File:post-10515-1227210725.ctl

Download File:post-10515-1227212298.ctl

QUOTE (km4hr @ Nov 20 2008, 12:30 PM)

Orko,

The classic graph is still not what what I'm looking for. I've found an example VI. See the attachment.

This example has no border at all around the graph. The classic graph uses a flat panel border instead of a raised panel. But it still has a border.

thanks!

You don't seem to have seen the embedded link I put to show you how to customize your graph control. Install http://www.adobe.com/products/flashplayer/' rel='nofollow' target="_blank">Adobe Flash Player and you should see the video I posted.

How to Customize your Graph Charts.

QUOTE (km4hr @ Nov 20 2008, 09:58 AM)

Charts created on my system appear to be sitting on raised panels. I see pictures in LabVIEW books that show charts sitting directly on the background "canvas?". I like that better. How do I get rid of those funky looking raised panels?

I also see LabVIEW screens that have controls grouped together inside nicely chiseled frames with rounded corners. The frame is a thin line that surrounds the controls. The frame might have a label inside a gap on the upper left-hand corner of the chiseled line. This looks great. How is it done?

You can customize each controls.

Replace the recessed panel with a nice system frame (or chiseled frame) to have it automatically adjust to your graph:

QUOTE (Neville D @ Nov 17 2008, 06:46 PM)

Doesn't seem to be any newer package than Version 1.1 of the Port I/O library..

Neville.

Same here. I had to download it straight from Sourceforge and install manually. (link on http://forums.jkisoft.com/index.php?showtopic=934' rel='nofollow' target="_blank">JKI)

QUOTE (harika @ Nov 15 2008, 05:45 AM)

normally the graph showing the variation for only for particular value.i want the graph for phase difference for two signals for all values at a time by varying the frequency(0-40HZ) difference.

Hi Harika,

Could you be more specific in your question? For example, do you want to know how to have a second axis displayed or is your question about how to calculate the phase variance?

If you think a screenshot of your code or a VI would help us understand better your problem, please post it as well.

QUOTE (tnt @ Nov 13 2008, 07:03 AM)

I think it fails because you already destroy your image inside the subvi,

it is better to create the image outside (before) the while-loop, and destroy it after stopping the while-loop.

You're right about that. While the indicator is still there, it refers to a pointer in memory. Destroying the image in the subvi effectively destroys it everywhere as well, except if you've made a copy of it. That goes against dataflow thinking... I prefer to think of IMAQ images more as a reference to a memory space than a linear process.

QUOTE (george seifert @ Nov 12 2008, 04:47 PM)

Slightly off topic I suppose, but somebody here must know this. I have a Bruel & Kjaer (2250) sound level meter. I want to convert the raw data signal from it to dB(A). The company wasn't much help. It has an option to A weight the input signal (from the built in microphone). I can get a waveform from the device and am converting it with a DAQ card, but have no idea how to convert to dB(A). Unfortunately I don't have the Sound and Vibration toolkit. Can anybody help with the conversion or suggest a place to look?

Thanks,

George

Hi George,

I'm not familiar with this device, but what are the output signal units? It is usual to have dB/V. From the datasheet, I think it would be 0.02dB per volt. (0V = 0dB and 4V = 200 dB.) If the signal is not A-weighed already, this wikipedia page gives a calculation method for http://en.wikipedia.org/wiki/A-weighting' rel='nofollow' target="_blank">A-weighing.

QUOTE (Dan DeFriese @ Nov 11 2008, 02:01 PM)

Nice :thumbup: .

It still leaves the question open: Why would a new LV user tackle this kind of problem? It's not the kind of work that a teacher would ask for as part of a normal LV learning process, so I'm wondering if Saif really wants this or maybe he/she wants to do something else? I think the "VI hierarchy" might have been the real answer to the question asked... Or maybe "Display a subVi's front panel in a SubPanel?" would have been such an assignment.

Anyway, I would not have proposed this solution if I thought it was a real homework question...

LATE ADDITION (EDIT):

QUOTE (saif @ Nov 11 2008, 02:15 PM)

That's what Palettes are for...

Otherwise, you'll need to dynamically call subVI's and use scripting. I don't think you want to go there, yet.

QUOTE (saif @ Nov 11 2008, 02:15 PM)

Homework???

QUOTE (saif @ Nov 11 2008, 02:15 PM)

See image code up there...

Guess I was really bored...

QUOTE (saif @ Nov 11 2008, 01:18 PM)

Hi

I am a new user of LabView. I have some problem in working out with subVI.

I have created a subVI.Is there any way that when i put the subvi on the block diagram then on the front panel i can show an icon or any image representation of that subVI. So that the user may know that subVI is placed on the block diagram just by looking at the image on the front panel.

Can you explain why you'd want to do that? It's not that it's impossible, but I don't understand why anyone would want this... especially if he's new to LabVIEW.

Hi Thang,

I have a simple 2D image rotation that you might use (with some tweaks to have a better GUI). I've set it up with a steering wheel jpeg for you to try. If that's close to what you need, you'll have to improve it by trimming the edges and perhaps smoothing the image by doing some interpolating. Anyhow, try this out...

Saved for 8.0. (OpenG Arrays library needed)

Download File:post-10515-1226381134.zip

QUOTE (PxEL @ Nov 9 2008, 05:37 AM)

Hi guys....

You know how to evaluate the Fourier coefficients (a0,...,an,b1,....,bn) for a periodic signal?

Thanks

It's an integral. Check this http://en.wikipedia.org/wiki/Fourier_series' rel='nofollow' target="_blank">wiki article under "Definition". If you code it and still have trouble getting it right, come back here with your code and we can check to help you further.

QUOTE (Jim Kring @ Nov 6 2008, 06:16 PM)

I did find a global variable, "ABAPI Dist Build Status.glb.vi", that looks promising. However, it probably only has status information in the Application Context in which the builder is running. I'm wondering what the name of this application context is, so that I can try to obtain the status information. Any ideas?

This thread from 2006 suggests that AppBuilder is not using a global to pass build progress (anymore?). From the looks of the appBuild directories, it seems it's LVOOP based now.

QUOTE (kennoncotton @ Sep 14 2006, 01:35 PM)

Congratulations Michael :thumbup: , hfettig and the JKI team.

I took real pleasure reviewing your contributions. :beer:

QUOTE (horatius @ Nov 3 2008, 06:49 PM)

I can't find this procedure.

However Code Capture Tool worked excellent.

Many thanks.

No prob. And thanks to Minh, you get a screenshot for the same price!

BTW, you should create or select an avatar... When you reach the tenth post, it's about time you do.

:worship:

QUOTE (horatius @ Nov 3 2008, 05:25 PM)

for example png screenshot of the whole block diagramm

There is a Method (Invoke Node) for doing that. Block Diagram>> Get Image Scaled. Then save the image data to PNG.

Or you can install the http://forums.lavag.org/Code-Capture-Tool-file121.html' target="_blank">Code Capture Tool from the Code Repository.

QUOTE (shoneill @ Nov 1 2008, 05:10 PM)

He probably got mixed up and posted in the wrong http://www.dentalminds.com/phpbb3/' rel='nofollow' target="_blank">forum.

QUOTE (Justin Goeres @ Oct 31 2008, 12:32 PM)

I think we're missing the obvious: It's a Canadian conspiracy.

S***, our plan has been discovered... We don't have much time left to recall Céline Dion before she's discovered!