pandaman

Ha. You can truly tell if a c/c++ programmer changes to LabVIEW when they still put // in their comment boxes...

I still do it even though I know it's redundant

^ may be reserved for bit exclusive or operations

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Oh yea, it's an exclusive OR bit operator....

Try x**y (where y is the exponent).

Neville.

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Wow, it worked! I wonder though why LabVIEW uses ** instead of ^... it would make much more sense to use the former since it works in the Eval f(x) methods. I am very curious as to how ^ operates in expression nodes, since I did receive output.

Thanks for the help :worship:

How would you express exponential expressions using ONLY expression nodes (found in numeric on functions bar)? I have tried 10^x, but the values are not desirable:

1------[10^x]-----11

2------[10^x]-----8

3------[10^x]-----9

4------[10^x]-----14

5------[10^x]-----15

6------[10^x]-----12

I have tried exp(), but it doesn't work...

...

Ok I thought of using property nodes and property execution > showFPonload (when select class > VI Server > VI is selected)... but it doesn't work.

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Ok sorry again i got it:

Application Control > Property node

Right click > Select Class > VI Server > VI

Left click on Property > Front Panel Window > Open

Sorry for posting... it was redundant

Is it possible to display subvi front panels only during certain circumstances (i.e. through invoke nodes)? I cannot find the method responsible for this.

Is it possible to display subvi front panels only during certain circumstances (i.e. through invoke nodes)? I cannot find the method responsible for this. I want this to be either a parameter in the subvi or something that alters the subvi's visibility in the main program.

I'm not sure I understand.

You say you don't have the application builder. I assume this means that you run your app as a VI, right?

In that case, you can either

a) change its extension, link the new extension to LV (so it opens it automatically) and give it your icon icon or

b) create a shortcut to your VI, right click the shortcut, select "Properties" and then "Change Icon" and find your icon file.

You will need to save it as an .ico file first.

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Yes, I did used to run my program as a VI, but i recently received LV 7.1 and an app builder... so I will use your previous advice (I want the actual app to have the icon while preserving the extension). The reason why my organization runs LV programs as VIs is because LabVIEW is installed on every computer we use. Thus, it makes it easy to modify code if we want to quickly change the behavior of the program. However, I can make copies of the object and source code for that matter. Thanks for the help!

Oh, after building the application... I don't have the appplication builder...

Dont worry, I found out where "index values" are... I can just implement them using property nodes. Thanks for the help!

Ahh!!! Not again!!! Sorry 'bout that, but I do not have LV 7.1. I gotst 6.1

Is it possible to synchronize two array indicators such that when the index of one array is selected, the values of both arrays at this index are displayed?

Ex: An array of x-values and an array of y-values are displayed on the front panel. The user is allowed to select the point # (point 0,1,2...) in order to view the co-ordinates.

Hello,

I was wondering whether it is possible to allow the icon in the upper-right hand corner of LV to be displayed in windows prior to opening. I already have an icon designed for my program and it would draw the user's attention much faster if it were visible prior to running. Any help on this would be much appreciated.

I lub eclipse :thumbup:

Have a look at this example:

...\LabVIEW 7.0\examples\general\uievents.llb\Draw Graph with Events.vi

-Franz

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Sorry, but I don't have Labview 7.0 :headbang:. How would you do it in Labview 6.1? If the example is in LV 6.1 under a different name, please direct it to me.

Thanx

So does anyone know how to return values that have been drawn on a graph or even drawing on a graph for that matter?

As far as recompiling everything, Labview only includes the ability to recompile VI's back 1 version.  So if You want to convert a VI from version 7.1 to version 6.1, you need to follow the steps below.

open the VI in Labview 7.1, and save for previous version 7.0

open the VI in Labview 7.0, and save for previous version 6.1

As for compatibility between versions, labview 6.1 will not open a VI written in 7.1. 

You have a few options here.

1. Write everything in 1 version of Labview

2. Write ALL you VI's in the earlier version of Labview, and treat them as read only.  You can then call them in both versions of Labview, the read only part will keep the system from recompiling them to a newer version.

3. Fork your VI's, make 2 versions, one for the old, and one version in the latest version.  You may be forced to do this, especially if you have VI's that use new features.

Hope this Helps.

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Aww... to bad I don't have LabVIEW 7.1....so if I can't use d/led 7.1 libraries . Oh well, I can always nag my dept. to get it. Thanks anyway.

Well thanks again Louis, and thank you dhuff. I didn't notice that as I write in LabVIEW 6.1 and use 7.0 libraries. This should save alot of time! I don't have to code completely from the ground up anymore! Thanks again :worship:.

Thank you both... I have however modified previous radio button code to work with my program (using the power of local variables and property nodes). Having done this, I am too lazy to use your method, aledain :laugh:. I will probably use it in the future though.

I have attached a diagram of the section of my code responsible for button handling. It may be useful to others who want coded button handling who require it to be in many nested structures.

EDIT: Also include wait for 1 ms somewhere near button code (within while loop)

I often use versions 6.1 and 7.0 of LabVIEW and have noticed that while LabVIEW 7.0/7.1 is backwards compatible, earlier versions of LabVIEW cannot open 7.0 vi's. This is a problem, as I require to open 7.0 vi's in 6.1. Is it possible to convert 7.0/7.1 vi's to 6.1 vi's if the source code is uniform for both?

I am currently writing a program in LabVIEW 6.1 that makes use of a series of radio buttons. I understand how to manually do this, but the complexity of my program makes it too much work. I have seen in other posts that there is a way to use a control for a codeless alternative to this dilemma, but the attachments have been deleted. If anyone knows how to do this, please attach the appropriate control or show me how it's done.

Thanks

I finally found what you were talking about and tested it out.  I put in a formula of y=x^3 and set input value x=2 -> Output = 8.  Then I switched the formula to y=3^x -> Output = 9.  So it looks like it works just fine to do what you want it to do, which is probably an upgrade that was included after LabVIEW version 6.1 since I'm assuming you did something identical and it doesn't work right for you.

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VEERRRY interesting... I tried it again and it worked! Silly me, trix are for kids! Thanks for the help, even if it was just showing me it worked.

Just enter it the same way LabVIEW displays it in a numeric.

If I understand what you're asking, it's easily demonstrated by wiring a string control to the Fract/Exp String to number function and looking at the output.

1.234e2 ( or 1.234E2) results in a numeric value of 123.4

Barrie

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Sorry for the confusion in my first post, but I want to input an exponential function, such as (.34)*(9.6)^x, rather than a number in scientific notation, and have it recognized by the Eval y=f(x) method found in

Block Diagram > Functions > Mathematics > 1D and 2D Evaluation > Eval y=f(x).vi

So you put "3^2" in a string for example and then what are you trying to do with that string?  How are you processing it?

Or are you saying you would like the 2 to appear as a superscript?

LabVIEW's math functions that handle exponential operations are located in the Numeric Palette.

Block Diagram > Functions > Numeric > Logarithmic > Power of X

That function "Computes x raised to the y power (x^y)".  It uses numerics as arguments, not strings, so if you wanted to use a string that read "3^2" and compute the value, you would need to convert the values to numerics and perform the Power of X function.

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Well, the problem with using the built-in exponent method is that I can only evaluate a single exponential expression, such as 3^2 and 4^5. Instead, I want be able to input an exponential expression with a variable, such as (1.5)*(2)^x, and use the evaluate y=f(x) function (Block Diagram > Functions > Mathematics > 1D and 2D Evaluation > Eval y=f(x).vi) to generate an array of doubles from an inputed set of bounds. I thought of using separate loops to generate the array using the Power of X operation instead of the Eval y=f(x), but it would be in discord with my hierarchy and variable placement. I tried to minimize my code by placing functions and variables outside of my control structures, but I guess this has screwed up the functionality :headbang:.

In Labview 6.1, I've been trying to enter an exponential function into a string and cannot figure out which character to use to denote the exponent (I've already tried the ^ key but to no avail). I know Labview has a method for handling exponents, but the program that I wrote calls for a function in a string.