Can I create array inside formula node

I need to create and use array (multidimensional) inside a formula node. My LabVIEW version is 5.1.The input and output from/to formula node do not necessarily being array. Thank you.

You need to declare a variable to be an array. To declare a multidimensional array of 32 bit intergers enter this:
int32 VarName[x][y];
Where x=1st dimension size (rows) and y=2nd dimension size (columns). You can then operate on this like you would an array in a text based language. Try the entering the example below in a formula node.
int32 i;
int32 y[5][2];
for (i=0;i<5;i++)
y[i][1] = x[i]+1;
Where y is an output and x is an 1D array input.
Hope this helps...
Brian

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Shift Register while Indexing Arrays in Formula Node

Hello,
I am having trouble using the formula node while indexing my two arrays. I keep getting "NaN" for my output array. I believe the problem lies within my shift register. My guess is that for the first calculation there is not a PreviousAngle so that is why it is giving me "NaN." For the first index I would like the value of the PreviousAngle to be 0. I am new to LabView and unsure what to do.
Thanks!
Christian Seymour
Solved!
Go to Solution.
Attachments:
Complementary Filter.vi ‏21 KB

The shift register should contain 0 by default since you are using a double [if uninitalized, the shfit register takes the default value of the data type. In this case, the default Double is 0], but you should explicitly initalize the shift register to a default value in most cases.
To do so, right click on the "previous angle" shift register and select "Create constant". This will create a Double value of 0 to fill in the register for the first calculation.
If you need a number other than 0 to start, you can just change this constant.
**Note: This is a good habit to have. Shift registers retain value as long as the VI is in memory. So if you run this more than once, it will have the value from the last execution automatically! This is usually unintended behavior for new LabVIEW users -- however you can sometimes take advantage of this feature in some applications and make it intended behavior
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If someone helped you out, please select their post as the solution and/or give them Kudos!

String array into formula node

Hello,
I am taking data from SQL, I am getting multiple rows of data for many different devices. I would like to wire the data into a formula node so I can sepearate and sort via script. However, I am getting an error for "Polymorphic terminal cannot accept this data type". Is there a work around? Can I not wire in a string array to a formula node.
/r
Travo

There are lots of basic string VIs that you can use to parse the string and separate out the individual fields. I would recommend "programming" your application using script nodes. Use the native language. LabVIEW is a fully functional and capable programming language.
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"Does anyone know where the love of God goes when the waves turn the minutes to hours?"
Wreck of the Edmund Fitzgerald - Gordon Lightfoot

Bug using array in formula node, LV6.0

Pass a 3-element integer array, containing values 5, 6, 7 into a formula node as input variable x. Pass variable y out. The formula node contains:
int32 y;
y = (x[2]-x[1]);
My result is 6. If the parentheses are removed, the answer is 1. Apparently adding the parentheses causes the expression to be evaluated as y = x[2-1];.
Has this been found/fixed? I have mailed NI separately.

In 6.0.2 it returns 1 in both cases.
"Adam Russell" wrote in message
news:ajcc8d$1a266r$[email protected]..
>
> "Bill Atkins" wrote in message
> news:[email protected]..
> > Pass a 3-element integer array, containing values 5, 6, 7 into a
> > formula node as input variable x. Pass variable y out. The formula
> > node contains:
> > int32 y;
> > y = (x[2]-x[1]);
> > My result is 6. If the parentheses are removed, the answer is 1.
> > Apparently adding the parentheses causes the expression to be
> > evaluated as y = x[2-1];.
> > Has this been found/fixed? I have mailed NI separately.
>
> It works correctly in 6.1. I'm at home so I can't t
ry it in 6.02.
>
>

How can I create a custom formula that checks if a PC file exists? (CR10)

Post Author: lgayosso
CA Forum: Formula
Hello,
I need to create a formula that validates whether a PC file exists or not to display a message ('File Found' or 'File not found'). I created a custom formula that displays the appropriate message based on a report field composed of the FilePath + FileNameWithExtension that works correctly if the field includes a value or not (Basic Syntax below):
If {ctDocumentImages.ImgPath} <> "" Then Formula = "File Found"Else Formula = "File not found"End If
Now I want to validate that the {ctDocumentImages.ImgPath} value corresponds to an existing file; that is, I need to check that the file specified at {ctDocumentImages.ImgPath} location truly exists to determine that the file is actually 'found'. How can I accomplish this?
Any help is greatly appreciated,
Lucio

Post Author: lgayosso
CA Forum: Formula
[email protected]:
( my file connection name was CrystalReports_Reports.File Name) I have generated a report, that shows all my rpt file names, size, last updated.... etc )
Go to database expert, create new connection, select file system data, your starting directory will be
genplex\E\JEMS51_Server\Imaging\Int\2007\..... you can then report on the file names found in that directory / subdirectory, etc... When creating the link you can select all files, or just *.rpt for example
Ok, so you define more than one connection on your report to be able to access the File System Object, right? The problem is that my reports are generic and meant for distribution for customers where no generic base folder will exist. The value of the starting directoy is then unknown, FilePath+Name then can be any value.
Lucio

Array in formula node

Hello everyone,
I am new in labview. I would like to display the coherence function with the correct frequency scale. For instance, I want it to be as follow: FreqAxis = 0:Fs/2/(N+1):Fs/2. where Fs is the sampling frequency and N the number of sample. I am trying to write using Formula node, but it is not working.
Thanks for your time and your help.
Axel

Thanks again for your comments and your time .
I have attached the .vi file and a screen-shot of the expected result (cohere2.png).
Cheers
Axel
Attachments:
Code_frequency.vi ‏531 KB
cohere2.PNG ‏17 KB

How can I create arrays through the same recursive process?

Hello again!
I want to create some arrays with names like array1, array2, array3 etc
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Do you know how this can be done? Thanks!
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I want to create some arrays with names like array1,
array2, array3 etc
through the same for loop.
Do you know how this can be done? Thanks!
for (int i = 0; i < 32; i++) {
byte[] array???=new byte[400]; You cannot create new names during runtime (array1, array2 are names).
You can create a map that associates Strings with byte arrays though:Map<String, byte[]> map= new HashMap<String, byte[]>();
for (int i= 0; i < 32; i++)
map.put("array"+i, new byte[400]);
// get array associated with array26:
int j= 26;
byte[] oneOfTheArrays= map.get("array"+j);kind regards,
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Using iPhoto, can I create events inside another event!?!? Is there a way??

I would like to create an event inside another one that already exists, is there a way to do that?
I want to create something like:
An album called "Euro Trip" and inside this album other albuns called "Madrid, Barcelona, etc"
By choosing "Divide events", they don't stay in the same "folder".
Can anyone help me?

Post this query on the iPhoto forum. There are people who are oriented to iPhoto issues.
I don't think you can do it. The only suggestion I can think of is to start a new iPhoto Library for 'Euro Trip'.
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Can you create folders inside an iPod?

I have an iPod video, and I want to know if it is possible to create folders in the iPod, other than the ones allready there.
e.g.
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Array output from formula node

How to get an array output from the formula node.I am trying to use a for loop inside the formula node and want an array output.

You cannot place a For or While Loop inside the formula node.
Here is what the Help Description says about the syntax inside the Formula Node:
Formula Node
Evaluates mathematical formulas and expressions similar to C on the block diagram. The following built-in functions are allowed in formulas: abs, acos, acosh, asin, asinh, atan, atan2, atanh, ceil, cos, cosh, cot, csc, exp, expm1, floor, getexp, getman, int, intrz, ln, lnp1, log, log2, max, min, mod, pow, rand, rem, sec, sign, sin, sinc, sinh, sizeOfDim, sqrt, tan, tanh. There are some differences between the parser in the Mathematics VIs and the Formula Node.
Place on the block diagram
Find on the Functions palette
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<SCRIPT type=text/javascript>if (typeof(writeVarRefs)=="function"){writeVarRefs("763");}</SCRIPT>
<SCRIPT type=text/javascript> if(typeof(lvrthelp763) != "undefined"){document.writeln(lvrthelp763)}</SCRIPT>
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<SCRIPT type=text/javascript> if(typeof(lvemb763) != "undefined"){document.writeln(lvemb763)}</SCRIPT>
<SCRIPT type=text/javascript> if(typeof(lvpdahelp763) != "undefined"){document.writeln(lvpdahelp763)}</SCRIPT>
<SCRIPT type=text/javascript> if(typeof(lvtpchelp763) != "undefined"){document.writeln(lvtpchelp763)}</SCRIPT>
<SCRIPT type=text/javascript> if(typeof(lvblackfin763) != "undefined"){document.writeln(lvblackfin763)}</SCRIPT>
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Example
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Array data in formula node

I want to take the Y value (being the amplitute) from the input signal and put it into a formula node. I keep getting the error signal as in the attached VI. Is there a way of seperating the value in labview?
Attachments:
Formula signal.vi ‏32 KB

Hi Cork,
yes, it's possible! And WTH: you can do it without a formula node with ready-to-use functions!
Best regards,
GerdW
CLAD, using 2009SP1 + LV2011SP1 + LV2014SP1 on WinXP+Win7+cRIO
Kudos are welcome

How can you Create a folder in pages?

I ve many documents all mixed together.. Can u create folders inside pages app...?
Thanksss

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Create array varible in TestStand 4.0

Hi gurus,
I have a doubt that how can we create Array of string in TestStand 4.0 using C#.NET environment.
I used following method, but failed to create array:
objPropertyObj.SetValStringByOffset(10,PropertyOptions.PropOption_InsertIfMissing,"SRU"); // exception here....
The other following method creates array with empty size:
objPropertyObj.NewSubProperty("SUBSTITUTE.SRU", PropertyValueTypes.PropValType_String, true, "Arrayw",10 );
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Thank you,
regards
RKK

You should post to the TS board.
Try to take over the world!

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The code I have just coded below is also right or wrong?
CLASS lcl_build_data DEFINITION.
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*-- Private Section declaration
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*** and Clear all internal tables and Work areas
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Since you are using the same object for your Selection screen related events, AT SELECTION-SCREEN, you would have to instantiate the object in the INITIALIZATION event. If your object usage is just for the data - In case you use the MVC design pattern, you should push back the object creation in START-OF-SELECTION.
Regards,
Naimesh Patel

How to difine global variable in Formula node?

I want to access the same vailable in different formula nodes, so I need to define a global or external vailables? How can I do this?

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Can I create array inside formula node

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