Actively changing number of elements in an array

How do you use a control in the front panel to actively change the number of rows in an array which full of numeric controls?
Is it possible to have this happen without the program to be running? Thanks for any help.
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Chris B. wrote:
Is it possible to have this happen without the program to be running? Thanks for any help.
So you want this to work at edit time? Are you talking about the number of visible elements or are you talking about the actual size of the array (these numbers are unrelated!).
In order for something to happen, "something" needs to be running. You could run another VI and use scripting to make changes to the array structure.
You could also make an Xcontrol containing an array and a numeric. Xcontrols are fully operational even if the VI itself is in edit mode.
If this is a program to run standalone, simply make sure the program is always running, but is in an idle state if nothing needs to be done at the moment. Now you can handle resize events if needed.
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Similar Messages

Total number of elements in an array

Hello,
I am trying to count the total number of elements in an array.
I have a simulate signal VI, that simulates a square pulse, this is being written into an excel file using the write to measurement VI, all for a given period of time.
I want to further chop a window of the signal depending on different paramenters (a trigger, which I intend to incorperate later, for now I am working of learning how to chop the data)
In order to chop the data I need to know the array size, I use the array size funtion, I right click on the appeneded array in the front pannel and click show last element (array size -1) it doesnt match with the number of rows in the excel file written by the write to measurement VI, in fact it macthes with the "number of samples" I selected in the simulate signal VI.
Am I doing something wrong?
Why is there a miss match??
I have attached my VI, Please help
Thank You
SP
Attachments:
FlashERGTrialVI 150218.vi ‏93 KB

Hello RavensFan
Thank you for the reply, I did incorperate the changes, but the same number is displayed in the indicator. I've attahced my VI
SP
Attachments:
FlashERGTrialVI 150218.vi ‏106 KB

How can I change all Inf elements in an array to a specific value?

I would like to change all Inf elements in my array to -1. Basically, I am looking for something similar to the range and coerce function, except that I want all values above a certain value to be a specific negative value, rather than go to that value.
I could use a case structure and go through each element in the array, but I am hoping to find something more efficient.Any ideas?
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P@Anand wrote:
I would do that in this way.
Here's a simpler version...
There are only two ways to tell somebody thanks: Kudos and Marked Solutions
Unofficial Forum Rules and Guidelines
Attachments:
Replace in Array.png ‏4 KB

Number of elements in an array

Hi,
I have been trying looking for a simple function to get number of elements is an array. Have gone though older posts but could not find answer to it.
The function should work for following examples:
char* name = "nInstruments"
float state[] = {1.0, 2.0}
I tried sizeof but it returns size of "type" in bytes. For example in example 2, it will just return 4.
Does someone know a way to do it?
Ciao
RB
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RB,
In C, if an array is declared on the heap, as opposed to on the stack as in your example above, the sizeof operator only returns the length of the pointer that holds the array which, in a 32-bit program, is always 4 bytes. This is because the compiler has no way of knowing how many elements that array actually holds. The length of a C array is a fairly fluid concept. The real size of the array is usually determined by some memory manager somewhere (usually, malloc), but it's not something that the language itself has anything to say about.
When you declare the entire array as a local variable, however, the compiler must create room for the full array on the stack, and therefore it is able to return the true size of the array via the sizeof operator. (The same is true if it's a global variable, even if it's not on the stack, in that case)
For this reason, using the sizeof(array) / sizeof(array[0]) trick is iffy. It might work, or it might not work, depending on how the array is declared.
For this reason, most C APIs that accept or return arrays, will usually also have some method of communicating the length of the array, usually as an additional parameter of some function. Because .NET APIs usually have no need to do this, the C wrapper for a .NET API in CVI does this for you when it handles .NET arrays. For example, here's what a function signature might look like:
int CVIFUNC Namespace1_Class1_Test1DArrays (Namespace1_Class1 __instance, int * inA, int __inALength, char *** outA, int * __outALength, Namespace1_Class2 ** refA, int * __refALength, double ** __returnValue, int * ____returnValueLength, CDotNetHandle * __exception);
Luis

How Do I Print the Number of Elements in An Array

How do I print: "There are ____ number of elements in the array?"

If you have a String holding a sentence, and if you split on non-empty sequences of whitespace (if the string has newlines in it, you'd probably need to pass the argument that makes \s match newlines, and for that you would probably need to use java.util.regex.Pattern -- see the docs and try some tests), when you'd get an array of Strings that were the non-whitespace parts of the original String. That makes for a reasonably good definition of the words in the sentence, although you could arguably get into some gray areas (does "isn't" count as one or two words? Does a sequence of numbers or punctuation qualify as a word?). In that case, counting the number of elements in the resulting array of String. using .length, would be a reasonable way to get the number of words in that sentence, yes.
But rather than asking for confirmation on forums, why don't run some tests?
import java.io.*;
public class TestWordCount {
public static void main(String[] argv) {
    try {
      BufferedReader in = new BufferedReader(new InputStreamReader(System.in));
      String line;
      while((line = in.readLine()) != null) {
        int count = // your code here, to count the words
        System.out.println("I see " + count + " words.");
    } catch (IOException e) {
      e.printStackTrace();
}Put your word-counting code in there, then run it from the command line. Type in a sentence. See how many words it thinks it found. Does it match with your expectation, or the examples given (hopefully) with your homework assignment?

Enable the Number of Elements in the Array

once the Un-Initializing the array(1D or Multi) Placed ,we can not select the Number of element to Enable.
byproviding the below option we can easily Enable the Elements in any array dimention.

Already possible by typing a value (usually the default value) once you've set the indices to the size you want to initialize

Iterating through every other (or specified number) of element in an array using a for loop

I am trying to go through an array but instead of autoindexing I want to skip every other element or maybe a number of elements that will be specified for the user.
Basic functionality that I want to acheive is the following in C code.
int temp_var = 10;
int i=0;
for(i=0; i<=1000; i=i+temp_var)
I am very new to LabVIEW and I did not know how to use internal variables.
Can this be acheived using shift registers?
I am attaching the code I currently have for this. Let me know what you think.
Thanks guys.
Solved!
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Attachments:
24_Sep_NchanNSamp.vi ‏44 KB

tbob wrote:
I have been asking for a new For Loop style that would allow us to specify start, stop, and step conditions, but it seems that many people are just not for this idea. Don't know why?
See here.
I wouldn't say there aren't many people for it. The idea you linked to was one of a half dozen of basically duplicate ideas, including another one of your own.
These two ideas have a fairly large number of kudoes showing people want the idea.
Smart Iterators with Loops
For Loop Increment

Counting number of elements in an array which aren't empty?

i tried using this method to count an array which has 100 elements but it doesn't go past the while statement which i cant figure out?
public static void countCust()
int cntr = 0;
int z;
for (int c = 0; c < 100; c++)
while (customer[c].indexOf(':') != -1)
cntr++;
javax.swing.JOptionPane.showMessageDialog(null, "There are " + cntr + " customers on record");
}

Are you getting NullPointerExceptions?
Are you sure customer[] has been allocated?
Are you sure each element in the array is non-null?
BTW, it's traditional to use variables in loops that are closer to their mathematical usage. I mean, for an array index, usually you'd use variables named i or j, unless the indices map to coordinates in space, in which case you'd use x, y, and z.
If neither of these is applicable, use a variable with a more meaningful name.

Set number of elements in a two dimensional array

Hi,
Does anyone know how to set the number of elements in a two dimensional array directly in teststand.
To set a one dimsional array is simple:
SetNumElements( locals.somearray,4)
Is there a method to do this for a two dimensional array?
Sean

From the help file (TestStand 4.2.0):
PropertyObject.SetNumElements
SetNumElements Method
Syntax
PropertyObject.SetNumElements ( numElements, options = 0)
Purpose
Sets the number of elements of a single dimensional array.
Remarks
This method is only valid for single dimensional arrays. The elements in the array retain their values. Use the PropertyObjectType.ArrayDimensions property to set the number of elements in each dimension of a multi-dimensional array.
Parameters
numElements As Long
[In] New number of elements for the array.
options As Long
[In] Pass 0 to specify the default behavior, or pass one or more PropertyOptions constants. Use the bitwise-OR operator to specify multiple options.
This parameter has a default value of 0.
So you could use, for example: Locals.MultidimensionalArray.Type.ArrayDimensions.SetBounds({1,0},{3,4}) to set an array to have three dimensions (1,2,3), each with five elements (0,1,2,3,4).

Get the number of elements in Array

Hi everyone,
Could anyone give me idea on how to get the number of elements in an Array (not number of rows) ?
I tried to find that in both property node and array functions but nothing.
Thanks,
-Kun

You are going to have to provide some proof that the Array Size does not work correctly. Right click on the input to it and select 'Create Indicator'. Run the VI. Go to the front panel and select 'Edit>Make Current Values Default'. Save the VI and attach it to your post.
You can also check the array size yourself. Right click on the index display of the array and select 'Advanced>Show Last Element'. I will bet you that number shown is equal to Array Size -1.
p.s. The number of elements in an array is equal to the number of rows in a 1D array. If you define the number of elements as anything else, you are mistaken.
Message Edited by Dennis Knutson on 04-21-2009 10:40 AM

How to find the elements of an array

I want to find the number of elements in an array, and I can't find the tutorial that shows how to find it. If anyone could point me in the right direction, it would be greatly appreciated.

warnerja wrote:
flounder wrote:
DrLaszloJamf wrote:
You mean x.length?<pbs>
Depends upon your interpretation of "number of elements in the array"
int[] numbers = new int[10];
numbers[0] = 42;
numbers[1] = 666;Number of elements in the array is 2 not 10.
</pbs>If you used something other than a primitive type for the array element type you could have a case. A value of integer zero for the other elements is still a value, so there are indeed 10 elements there.Even if it were not primitive, every element would have a value. That value would either be null or a reference.

How can I change the properties of only one element in an array of booleans?

I'm displaying an array of booleans to my operators, with each boolean in the array representing some system status check. Some of these checks are critical and some are not, therefore I want some of these booleans to have a different color when in the TRUE state (Red for the critical ones and Yellow for the non-critical ones). I can change the boolean colors with a property node, but that effects every element in the array. Is there any way to change a property of an individual element in an array? I know that I could take the incoming array and break it into two arrays - one for critical and one for non-critical, but this system is replacing an older system and the operators are accustomed to seeing their indicator lights a certain way and I'm trying to replicate what they had exactly.

Here's what I had in mind
Of course you can use as many colors as you want.
Message Edited by altenbach on 12-21-2005 04:53 PM
LabVIEW Champion . Do more with less code and in less time .
Attachments:
LEDarray.png ‏7 KB
ColorArray3.vi ‏23 KB

How to change the properties of individulal elements in an array?

Hi all,
I have an array (size is 25) of string and I want to disable and grayout half of them. But how do I do it? How do I change the properties of individual elements in an array? I have tried to use some of the examples given in the discussion forums, but it didint work for the task mentioned above. Anybody would be able to help me with a suitable example that can be specifically used for disable or enable the individual array elements?
Dev

Telemaque wrote:
The user will see the first half of the string elements filled-in and the lower half grayed-out (to be filled in later). Make a test VI, play around.
... except that all elements "greyed out" with this method contain the default string for the array element (blank by default, but changeable). There is no way to have meaningful, unique text in the greyed out elements.
I would suggest to use a listbox as control/indicator. Here elements can easily be disabled programmatically.
LabVIEW Champion . Do more with less code and in less time .

Can we change the property of each element of an array using property node or by other methods?

Hello all,
Can we change the property of the elements of an array. For example:
I have an array of combo-boxes. Can i have such a scenario that different combo-boxes of the array will have different items to select an item.
I am able to set the different "values" in different combo-boxes bu using "to be more specific class" property node.
But i could not set the different item list in different combo-boxes.
Please give me the solution.

Thanks a million dave!!!!!
I have learnt a very new and innovative thing...
I just wanna ask you one more question in the above context.
Can i have listbox or combo-box in a table just like in an excel sheet where we can have listbox by using "data validation" property for different cells having different list.Can i have this in labview. Because for this i have to super-impose the combo-boxes on the table and treat them separately.
We have to take those combo-box values and put in table and then store it.I have attached one VI to show the scenario.
And this is the alternative solution of the array problem which u have already given. So please suggest me between the two or any alternative solution.
Thanks,
Ankit Madaan
Attachments:
Recording _Table.vi ‏19 KB

Change properties of a cluster element withing an array of clusters

Hello all,
I have an array of cluster that is shaped as a line with different display elements.
A list or a tree wouldn't have made it, so I had to use a cluster and make a table.
The problem is that I want to change not only the text but also the text color.
Individually.
I found this :
http://www.ni.com/example/30904/en/
But it change the property in all the clusters in the array, not just the one I need.
Some people have the same problem :
http://forums.ni.com/t5/LabVIEW/Reference-to-Array-of-Clusters-with-an-array-element/td-p/1006427
http://forums.ni.com/t5/LabVIEW/Different-set-of-values-for-two-rings-in-an-array-of-clusters/m-p/10...
http://forums.ni.com/t5/LabVIEW/array-of-clusters-get-references-to-all-the-clusters/td-p/1079456
http://forums.ni.com/t5/LabVIEW/How-can-I-reference-the-properties-of-a-control-in-a-cluster-in/m-p/...
http://forums.ni.com/t5/LabVIEW/Writing-only-to-certain-cluster-elements-in-an-array-by/m-p/2200728
http://forums.ni.com/t5/LabVIEW/Update-Properties-Of-One-Control-In-An-Array/m-p/3015501
http://forums.ni.com/t5/LabVIEW/Array-of-clusters-and-in-the-cluster-is-a-bar-meter-how-can-I/m-p/15...
http://forums.ni.com/t5/LabVIEW/Property-node-of-a-control-inside-of-cluster-inside-an-array/m-p/946...
Obviously, while in a list/table or tree you can change the property of an individual
cell (font, color) you cannot do it within an array of cluster, by some sort of magic,
the property of a cluster element (font, color) are all linked together, hence rendering
the use of an array worthless.
A possible hack is proprosed by using control masking, setting one visible and the
other invisble, swapping their position, whatever. It's a hack you have to perform,
hence add another code to maintain.
Is that still the case or is there now a more official way to handle individual cluster
properties, not just its data ? After all that's a common real-life example that should
be handled by Labview. In my opinion.
David Koch
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altenbach wrote:
One of the elements could be a 2D picture indicator of about the same size. You can write text in any color using picture functions.
Here's what I had in mind. Seems to work just fine (I would fine-tune the font, picture border, etc. but this should get you started).
LabVIEW Champion . Do more with less code and in less time .
Attachments:
ColorText.png ‏13 KB
ColorText.vi ‏9 KB

Actively changing number of elements in an array

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