Initializing data in an Array of Clusters

First, thanks in advance for reading this request.
Second, the situation:
I am using an array of clusters for process control.
The cluster contains a boolean, a typedef ring control, and two numeric controls (doubles).
Depending upon the user-requested operation I need anywhere from four to 20 cluster elements in the array.
Raw data for the two numeric controls are contained as elements in three different input clusters.
Each numeric control in each array cluster can use from none to four elements from the input clusters with various additions and subtractions (no mults or divs).
The boolean and ring can be set as constants for each element based on the user request.
Third, the request:
Is there a simple way to initialize the values in the cluster (and hence the array) without having to run wires everywhere?
I have been writing embedded code and PC applications for many years and am only recently tackling LabView.
In C, I would create a structure of the four elements and then create and array of structures.
The initialization would require a few lines of code.
I have tried using formula nodes (perhaps incorrectly).  All they do is remove the Numeric blocks (like + and -), but they don't create the cluster.
I am sure that there is an easier way of accomplishing what I need to do, I am just too inexperienced to know what it is.
Any help or suggestions is welcome.
Thanks in advance.

Create a cluster with the desired default values as diagram constant, wire it to "initialize array" and wire the desired array size.
The output will be the desired construct that you could write to e.g. a local variable of the target.
I hope I understood you correctly. If not, attach a small VI containing your array.
LabVIEW Champion . Do more with less code and in less time .

Similar Messages

  • Data entry in array of clusters

    Hi guys. I have 2 array of clusters in tab. My cluster have different types elements. I need  get referance data entry. 
    I can do it for one array of cluster with dynamic event structure but cant do it for other. 
    My vi in attachment.
    Can anyone help me for solution?
    Thanks.
    Kerem
    Solved!
    Go to Solution.
    Attachments:
    x1.vi ‏21 KB

    Why can't you just duplicate the same for the Array 2? I am not sure what is the actual problem you are facing but duplication did work.
    The best solution is the one you find it by yourself
    Attachments:
    x1_Anand.vi ‏29 KB

  • Initializing an array of clusters in a CIN?

    I'm trying to write a CIN to connect to a mySQL database, retreive some information, and return it to labVIEW for display. The connection works perfectly using ODBC, but I'm having major trouble getting the information back to LabVIEW. I'm new to CINs and I'm still slightly confused as to how the different structures work. I want to return the data in an array of clusters (using struct names, a 'Set' of 'Records'). LV generated the structs, and I simply renamed some of the fields/names. The code I have so far works up to the point specified in the source below, when I try to initialize the array for data entry. I think what's throwing me off is the conplexity of my structures. Since it's an array of clusters, and not an array of say strings or integers, I'm getting confused. If anyone could help me out by telling me what's wrong with my code, and/or filling in the section of the while loop I'm rather clueless on.
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    This looks incorrect:
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    Did you let LabVIEW generate the C file??
    When you pass an array of clusters to a CIN, what is passed is a handle to the array. You are declaring a pointer to a handle. I just did a test passing an array of clusters to a CIN. The C file looks like this (comments are mine):
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    int32 Num1;
    int32 Num2;
    } TD2; // the cluster
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    int32 dimSize;
    TD2 Cluster[1];
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    Notice that it passes you a HANDLE, not a pointer to a handle.
    On this line:
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  • Call library function node with array of clusters using array data pointer

    Hello all.
    I am writing a LabVIEW wrapper for an existing DLL function.
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    Batya
    Solved!
    Go to Solution.

    OK, here is more detailed information.
    I have attached the VI.
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    #include "extcode.h"
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    int32_t control;
    int32_t data;
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    typedef struct {
    int32_t dimSize;
    TD2 data[1];
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    typedef TD1 **TD1Hdl;
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    int32_t Load_Transmit_FIFO_RTx(uint32_t handle, uint16_t channel,
    int32_t FIFOnumber, TD1Hdl *data, int32_t numWords, int32_t *actualLoaded,
    int32_t *actualStartIndex);
    int32_t Load_Transmit_FIFO_RTx(uint32_t handle, uint16_t channel,
    int32_t FIFOnumber, TD1Hdl *data, int32_t numWords, int32_t *actualLoaded,
    int32_t *actualStartIndex)
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    #include "extcode.h"
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    typedef struct {
    int32_t control;
    int32_t data;
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    typedef struct {
    int32_t dimSize;
    TD2 data[1];
    } TD1;
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    int32_t *actualStartIndex);
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    int32_t FIFOnumber, TD1Hdl *data, int32_t numWords, int32_t *actualLoaded,
    int32_t *actualStartIndex)
    /* Insert code here */
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    t_DispatchTable *pDispatchTable = (t_DispatchTable *) handle;
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    borland_dll is just "__declspec(dllexport)"
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    typedef struct {
    int control;
    int data;
    } TD2;
    typedef struct {
    int dimSize;
    TD2 data[1];
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    usint nextEntryToTransmit;
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    *actualStartIndex = 0;
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    *actualStartIndex = ptxFIFO->nextEntryToLoad;
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    //also if nextEntryToLoad == nextEntryToTransmit the FIFO is full and we exit without loading anything
    if (( (( ptxFIFO->nextEntryToLoad >= ptxFIFO->numEntries) && (nextEntryToTransmit == 0)) ||
    ( ptxFIFO->nextEntryToLoad == nextEntryToTransmit)) && (ptxFIFO->nextEntryToLoad != INITIAL_ENTRY)){
    *actualLoaded = 0; //FIFO is full already, we can't add anything
    return 0; //this is not a failure, we just have nothing to do, this is indicated in actualLoaded
    numLoaded = 0;
    lclData = (usint *)data; //must use 16 bit writes to the module
    //conditions are dealt with inside the for loop rather than in the for statement itself
    for (FIFOentry = *actualStartIndex; ; FIFOentry++) {
    //if we reached the end of the FIFO
    //if the module is about to transmit the first element of the FIFO, the FIFO is full and we're done
    //OR if the module is about to transmit the element we're about to fill in, we're done - the
    //exception is if this is the first element we're filling in which means the FIFO is empty
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    ((FIFOentry == nextEntryToTransmit) && (FIFOentry != *actualStartIndex) )){
    *actualLoaded = numLoaded;
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    if ( FIFOentry >= ptxFIFO->numEntries)
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    //load the control word
    ptxFIFO->FifoData[FIFOentry * 3] = *lclData++;
    //skip the high of the control word, the module only has a 16 bit field for control
    lclData++;
    //now put in the data
    ptxFIFO->FifoData[(FIFOentry * 3) + 2] = *lclData++;
    ptxFIFO->FifoData[(FIFOentry * 3) + 1] = *lclData++;
    numLoaded++;
    //we're done because we loaded everything the user asked for
    if (numLoaded >= numWords) {
    *actualLoaded = numLoaded;
    ptxFIFO->nextEntryToLoad = FIFOentry+1;
    return 0;
    //if we reached here, we're done because the FIFO is full
    *actualLoaded = numLoaded;
    ptxFIFO->nextEntryToLoad = FIFOentry;
    fclose (pFile);
    return 0;
     As you can see, I added a temporary diagnostic with the structures that were created in the "Handles by value" case, and print out the data.  I see what is expected, whichever of the options I pick in the CLN!  
    I understood (from the information in the two links I mentioned in my original post, and from the name of the option itself) that "array data pointer" should pass the array of data itself, without the dimSize field.  But that does not seem to be what is happening.
    Batya
    Attachments:
    ExcM4k Load Transmit FIFO.vi ‏15 KB

  • Labview How to specify 1d array of clusters as data types for variant to data

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    Solved!
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    Attachments:
    Error During Cycle Controls.zip ‏3107 KB
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    Chris Johnson wrote:
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    Also, again, to confirm what I think I already know. When the event completes it outputs whatever data you output from the structure and then you can place it in a shift register. Where does this go until the next event takes place?
    I don't understand what you're asking.  Where does what go until the next event?  If by this you mean the data in the shift register - it stays in the shift register, accessible at the corresponding terminal on the left side of the loop.

  • Type defined array of clusters for holding configuration data - setting default values for each array element

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    Solved!
    Go to Solution.
    Attachments:
    CM_AnalogInputs.ctl ‏11 KB

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    Wreck of the Edmund Fitzgerald - Gordon Lightfoot

  • Reference to Array of Clusters with an array element

    Hi,
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    You cannot use references in the same way that you use pointers around in C. LabVIEW does not manage memory in the same way that C does. This is actually a good thing, though C programmers find it "cumbersome" or "restrictive". I have also programmed in C, and frankly I prefer LabVIEW's memory management any day of the week.
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         JOptionPane.showMessageDialog(this,"Error Opening File",
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    at FileReductoin1.readTheFile <FileReduction1.java :172>
    at FileReductoin1.readFile <FileReduction1.java :110>
    at FileReductoin1.actionPerformed <FileReduction1.java :71>
    .

    1) Next time use the CODE tags. this is way too much unreadable crap.
    2) The problem is your String[][] data.... the only place I see you do anything approching initializing it is
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  • How do you store parsed XML data in an array

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    Ok, yer going about this all the wrong way. You shouldn't have to maintain a count of all the elements. Basically you are locking yourself into the XML tags not only all being there but are assuming they are all in the same order. What you should do is in your characters() method, put all of the characters into a string buffer. Then, in endElement() (which you dont use btw, you should) you grab the information that is in the string buffer and store it into your Customer object depending on what the tagName is.
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  • Brick Wall Problem: Array of Clusters, Size of array from reference

    Good Morning Forums,
    I have hit a brick wall with my application and I am hoping somebody can help!
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    Cheers for any help
    J
    John.P | Certified LabVIEW Architect | NI Alliance Member
    Solved!
    Go to Solution.

    John.P wrote:
    Good Morning Forums,
    I am not worried about casting the data (once i determine the size this bit is no issue), I just need to determine the size (and preferably number of dimensions) of the array. Can this be done?
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    J
    There seem to be a couple of potential solutions.:
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    Jeff

  • How can I get a ref to a ring in a cluster that are in a array of clusters?

    I have a cluster (typdef'd) with controls. Two of the controls is rings. I place that cluster in a array. I then fill the array of clusters up with data. Can I get the ref to the rings in each cluster? I must load them, individually, with strings[].
    Solved!
    Go to Solution.

    Mike,
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    Attachments:
    example.vi ‏54 KB
    LiggInmatCluster.ctl ‏22 KB

  • Keyboard "tab" control in Array of Clusters

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    Seems overly complicated to me.
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    Sorry for the wall-of-text post (and the preposition hell).  Thanks for your input.
    Solved!
    Go to Solution.

    Well I've gone and gotten the tabbing behavior you're looking for.
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    -Barrett
    CLD
    Attachments:
    Tab through cluster array elements.vi ‏28 KB

  • Change properties of a cluster element withing an array of clusters

    Hello all,
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    Solved!
    Go to Solution.

    altenbach wrote:
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    Attachments:
    ColorText.png ‏13 KB
    ColorText.vi ‏9 KB

  • Change properties of controls in an array of clusters

    Hello,
    my latest problem:
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    However, for each cluster, once a sub-control is defined, i would like some other sub-controls to either become invisible, visible, change ring values...etc.
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    ... And here's where I keep assorted lengths of wires...

    Hey good work!
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    Certified Professional Instructor
    Certified LabVIEW Architect
    LabVIEW Champion
    "... after all, He's not a tame lion..."
    Be thinking ahead and mark your dance card for NI Week 2015 now: TS 6139 - Object Oriented First Steps

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