issues of data type of waveform in labview

Similar Questions

• issue of data types

  Hi all
  What is the difference between varchar and nvarchar data types?
  Nvarchar is better for database performance?
  If I have a table with several columns such as number, and I do a lot of calculations, what is the best way to use indexes?
  Thanks in advance.
  
  John B

  user9542267 wrote:
  Can you explain what you mean by "all the space reserved varchar2?

  Means if I said varchar2 (20), in the field of the table is to book and use 20 places, although we do not store any data. Do you know what I mean?

  This is false. VARCHAR2 and NVARCHAR2 are of variable length data types. If you said TANK so I would agree with you. I recommend you re-read the definitions of data types.

• Data type of waveform manipulation

  Hi all

  I have a table of 1 d waveform data out DAQmx Read.vi. I want to be able to add or multiply a scalar number specific to all data points in a specfic channel (array element). What is the most simple/more efficient way to do this?

  Thank you!

  There is a "waveform scale and Offset" in the auxiliary analog waveform palette palette.

  If you only want to scale each eleme in the table then put that VI is a loop For and pass the scale and the shifts you need.

  Ben

• Issue of data type

  I don't know what type of data my var. currentSWF what is that?

  function onCompleteHandler(loadEvent:Event)
  {
       var currentSWF = loadEvent.currentTarget.content;
       swfHolderMC.addChild(currentSWF);
  }
  

  Thank you much for the help with that!

  MovieClip:

  function onCompleteHandler(loadEvent:Event)
  {
       var currentSWF:MovieClip = MovieClip(loadEvent.currentTarget.content);
       swfHolderMC.addChild(currentSWF);
  }
  
  

• How to create the type of waveform data

  Hello

  I work with the oscilloscope TDS 30xx series and I want to create the data type of waveform in the waveform of Fetch VI.

  I have problems with that. Can someone help me?

  I don't know how to data table of waveform to the creation of a data type.

  Is attached a photo of the VI and the VI himself

  Well, if you want to build a waveform of Y, dT and T0, you can still use the function named "build the waveform.

  

• Spend the MATLAB data types 'cell' between MATLAB script nodes in LabView?

  Hi all

  I need to pass a variable of data type of cell of a MATLAB script node in LabView to another, but the cell is not listed as a data type 'exit' in the script node.

  Is it possible to do without converting them into a 2D array?  Each column of my cell has a different number of lines...

  Thank you!

  Mike

  Too bad...

  Rather than use a typical LabView, I just say

  assignin ('basic', ' varname', varvalue ");

  in the first script and varname called from the second node to get my cell.

  Easy... duh leaving here if anyone has the same issue in the future.

• Creation of Data Type when the script crashes LabVIEW

  When you use the script (LV2010) if I call the Create method of Data Type (available appeal node when a reference to the BD is cable), if I have all but 1 up to the wiring on 'style' terminal, LabVIEW, it blocks. LabVIEW then restarts with an error message saying that "the last time that you have run LabVIEW internal error or accident took place in lvmain.cpp, line 1756. If I have wiring 1 However, it creates a constant fine.

  I see in the context-sensitive help that it always creates a control at the start, but it seems that I can't get it to create a constant. So, okay, I decided to go around, create the constant, take the new object refnum he returned and there to change the constant in one control... but I can't get this work. Can someone point me in the right direction? Here is the code and the screenshot; This is a quick drop plugin.

  It is intended to run on a cluster that is perceived as an icon if you want to test, you need to create that.

  I presented the 'style' value, 0 if if you don't want to plant LabVIEW, set it up to 1.

  

  No time for an in-depth exploration now.  Create from Datatype killed my LV10.  What I was able to do after creating a constant of cluster, the consultation as an icon and select it.  (1) with the scripts, create a new VI and stick that the constant to figure (2) mount the pasted objected to the ClusterConstant and the change of control.

  I think I know where you're going, should be interesting.

• Convert a U8 array to a data type of LabView

  In my code, the entrance is a fixed-length U8 array reflecting the data in memory, I need to convert it to a predefined data type. For example, the first 2 elements U8 in the arrary must comvert a U16, then 4 U8 U32 data elements data. I wonder if there is an easy way to do this kind of conversion.

  Type casting Man and his trusty Sidekick Unflatten chain are itching for action.

  

  Use Unflatten chain if you have problems with "endianness".

• Get the Data Type of queue

  I'm working my way through my first vi producer consumer and I have two questions.

  1 I am the queue data x, y samples acceleration waveform type z. The code snippet shows how to set the data type in the queue to get. It is rather ugly and disturbing, even if it seems to work.  Is there a way more elegant and beautiful to set the data type?

  2. the sampling frequency of the accelerometer is 5120 Hz.  The DAQmx Read buffer is 1024 length samples.  Therefore, it takes 200 [ms] to fill the buffer.  I put the metronome 100 [MS] to ensure that the producer is not without samples.  This means that the loop While producer will spend much of its time waiting.  Right?  Given the wait cost anything?

  In ProducerConsumerExample.vi of LabVIEW, the sampling frequency is 10000.  The size of the read buffer is 1000.  And the metronome is set to 100 [ms].  The sampling frequency of the device comes from the hardware device in the cDAQ.  100 [ms] interval comes from the PC.  It will not be a mismatch?  I would like to understand this before I put my metronome to 200 [ms].

  

  Arizona_Joe wrote:

  Then, can shed you some light on the behavior of the loop while you mentioned is not a metronome that is is punctuated by DAQmx? I think it would do a lot of rotation.

  It is not spinning as he waits inside the DAQmx Read for samples N must be obtained.  This isn't a request for data.  It takes time to collect these samples.  That length of time depends on your sampling rate and how many samples you request.  So because he is waiting inside the DAQmx Read, there is no need to add an additional wait.  Let the DAQmx Read limit the rate of the loop.

  It's actually like the loop of consumer for the consumer to the producer.  Playback of the queue will limit the rate at which that loop runs.  It should therefore no waiting.

• The multiplot XY graphs & Data Types

  Currently working on four tracing data sensors of pressure on a XY plot, but up to this impossible. In addition, I do not know if I use the correct data type.

  As you can see in the image below, my code is taking measures of the DAQ Assistant and proceeds to divide the data into four signals before taking their average. My predecessor was thought to build a matrix of these signals of four split with what I suppose is the timestamp. The problem is that only one set of data being plotted right now. I tried to change the order of things that I use a cluster as my data type, but I always feel to get an error.

  Recently I saw this webpage https://decibel.ni.com/content/docs/DOC-5129 for more help, but imitating the way they don't seem to work for my code.

  Can anyone help?

  All I see are 1 d arrays. A matrix in LabVIEW is special data type used for... you guessed it, matrix calculations. Do not use it interchangeably with table.

  The main problem is that you send a single cluster in the XY graph, which means a single parcel. What you want is an array of clusters. The clusters will be a beam of table 1 d of timestamps and D 1 table of measures. But it is the hard way to do it, and this means you need to keep all your data as the tracks of the loop, with a lot of unbundling, build tables and rebundling. Crossrulz wrote a great nugget on How to use a sporadic data graphic , which makes things much easier, because the chart holds the story for you. Take a look at this post, and if you want to have several plots, you can just make a table of the waveforms, as I did below. Where you see the 'random number' dice, you will put your unique measurement data you acquire every time as the iteration of the loop. You can test the program by running and clicking on the Add Point"" button.

  

• Other data on the same chart Labview DAQ +.

  Try to do something fairly simple in labview. We read up to 16 analog inputs continuous (in a loop), the merger signals and display on a single diagram.  Now, I have a few other data from another (non DAQ) instrument playing in another loop much more slow.  Problem is I can't over all the data through the data acquisition loop to display on a single chart.  I even tried to build the waveform in the loop of data acquisition.  But whatever by entering seems to cause the whole thing to stop and no data is read.  How is this best?

  Hello

  Looking at your screenshot, it seems that you have a data type double wired in your queue get in the middle of your attached screenshot. I would recommend a constant of waveform of the queue to get instead of the constant double wiring. This will define your data in the form of wave type and porbably will allow you to get the names of waveform.

  The constant waveform is located on the range of functions under the waveform > Analog Waveform > constant waveform.

  Please see the screenshot of clearing-up joint.

  I hope this helps!

• DLL custom data type

  I try to use a DLL in LabView that talks about an acquisition card. One of the functions requires a custom data type (MID2250_MDConfig_t) that LabView does not support by default. It is defined in the C header file as follows:

  typedef struct
  {
  int CoordsX;
  int CoordsY;
  } MID2250_PointCorrds_t;

  typedef struct
  {
  MID2250_PointCorrds_t ULPoint [4];
  MID2250_PointCorrds_t BRPoint [4];
  unsigned short u32SADThresholdValues [4];
  unsigned short u32MVThresholdValues [4];
  unsigned short u32SensitivityValues [4];
  } MID2250_MDConfig_t;

  Is there a way I can integrate this data type in LabView correctly. I saw people talking about wrapper dll on this forum but I'm a bit confused as to who. Can I create a similar cluster in LabView and pass it to the function using "node of the library call?

  abdel2 wrote:

  I try to use a DLL in LabView that talks about an acquisition card. One of the functions requires a custom data type (MID2250_MDConfig_t) that LabView does not support by default. It is defined in the C header file as follows:

  typedef struct
  {
  int CoordsX;
  int CoordsY;
  } MID2250_PointCorrds_t;

  typedef struct
  {
  MID2250_PointCorrds_t ULPoint [4];
  MID2250_PointCorrds_t BRPoint [4];
  unsigned short u32SADThresholdValues [4];
  unsigned short u32MVThresholdValues [4];
  unsigned short u32SensitivityValues [4];
  } MID2250_MDConfig_t;

  Is there a way I can integrate this data type in LabView correctly. I saw people talking about wrapper dll on this forum but I'm a bit confused as to who. Can I create a similar cluster in LabView and pass it to the function using "node of the library call?

  Since the tables are all fixed size (and not huge), they really are inline in the structure. This means that you can simulate a cluster containing many elements inside because it is the elements of the array. The first Point of the UL would be a cluster containing 4 cluster with each two int32 in it. Ditto for the second element. The third is a cluster with 4 uInt32 and so on.

  Then configure the setting to adjust the type and thread this cluster, and voila.

• How to create a custom data type

  Hello

  I'm using Labview 2009 and I am trying to create a custom data type and link it to the global variable that will be deployed in cRIO 9073. I couldn't find a method to achieve this. Please suggest a way to do this.

  Thank you

  Guilhem

  Right-click on a control and go to advanced-> customize.  This will open the control editor.  Change the type of a control to a Type def.  Customize if necessary and save the control.

• Problem of XML data type

  I am trying to unflatten data from an xml file but my entry type for the type on the unflatten my guess isn't valid, and I get error 1106.

  Is attached, the file xml and VI

  XML file is in text loading constraints

  Your cluster of data type does not match your XML file. Fixed VI (LV version 2013) is attached. However, the file you posted seems to be a single element, not the entire file, so I can't verify that it works.

  If you have a previous version of LabVIEW, the cluster lacked a time stamp and had a cluster at the end which should be a string.

  Double post here.

• To change the data type of control/led

  Is it possible to change the underlying data type of the indicator or a control?  I a VI that I want to use that accepts any type of data (essentially data varriant) and display it accordingly.  I have different controls selected to display data of different types in the sense of data vs decimal boolean data vs integer, but certain types of data will be of type uint32 vs int16 vs uint64 etc..  Is it possible to programmatically change the data type, so I need to have all the combinations of indicators?

  The short answer is no. The long answer is that LabVIEW has not 'generic' controls that allow you to display any type of data (apart from the variant of course). There are several ways to address this problem, but all require you as the programmer to manage explicitly each type of data you could possibly meet. Here are some possibilities (in no particular order), please let me know if you would like to help a particular implementation of these.

  1. Force incoming data to variant, use the info option to determine the data type of the original data in a case structure (open G can do this VERY easy), have an indicator on the front panel for each type of data you want and hide those unused
  2. Use a sub-group of experts on the front panel and sub - vi call of to view specific types (that lends itself very well to encapsulate your data in a class and you leave OOP allows to expand into different types of data)
  3. Use a tab with the variant (similar to option 1) control put each kind of data in its own tab, enable only the current
  4. Do a Control-X to accept a Variant option 1 under the hood
  5. Just as a string of format and use a string indicator

  That's all I can think of right now, once again, let me know if you need more information/help on the options.