By Mahbod Morshedi
I m trying to build a software, and data management has become too complex. In short, it is acquiring data from three channels and doing some calculations and then showing and reporting that data for the user to make a fitting decision. The user then, can save the file and import the saved worked-up file later to view or manipulate.
The data consist of three interdependent data set, and so far, I have collected the dat as an array of clusters (size 3) for three sets and kept user input data in the same manner. I am also using a simple "producer/consumer" design. However, I think that may have been a mistake, and I might be able to do a better job using either actor or QMH design, especially since I need to think about adding the acquisition part (which is not yet developed). The thing is that I have not used oop before at all and am not quite sure if this is the correct approach and how should I bundle my data. Considering that the data (not all but some) need to be accessed by other classes if I goo with oop.
For example, should I keep the data as separate class data and use methods for override or keep it as an array in the parent class and use static methods and only use child classes for graphing. These are the type of questions I am struggling with. Also, can anyone help me decide between DQMH, Actor or just standard Producer/Consumer patterns, please? I am completely lost.
Thank you in advence.
This is how the front pannel looks like:
And this is the data set for the system (which I am keeping as an array) there will me more data added to this as the capabiliy grows.
I tried to create a template based on OOP for QMH. During development I have been confronted with infinite crashes of LabVIEW so I decided to slow down with this project and open it to the community. I finished my working example and stopped for now.
So if anyone is interested to play around with the code, see attached ZIP file (LV 2020).
By Marko Hakkarainen
I had some time to learn about new interfaces and finally I could implement my collection class as I had envisioned. I didn’t want to use iterable and iterator names, because I thought that would have been too bold a claim.
The original version of the collection class was (and is) used as a collection of sequence steps. Each element can be either a sequence command (send message, wait timer, wait complete etc.) or another collection of commands (sub-sequence). That’s the reasons for the labels and search method. Otherwise it is just a fancy (Rube Goldberg) array.
Next method is recursive and it steps through all elements in the collection. Execute is only method, which requires override.
For now, it’s at least an exercise in new interfaces. I don’t know if it’s useful enough to be in the code repository, but I can polish it up if needed.
Certified LabVIEW Architect
Iterable Collection LV2020.zip
I am reading big TDMS files (~1GB) and I try to minimize memory usage.
I read a signal once and I want to keep it for later usage, so I tried to write it to a DVR in the hope that I have only one instance of the data in memory.
However the task manager tells me that uses 2 times more memory than it should.
I think the problem is that the array is not deallocated although I don't need it after writing it to the DVR.
Is there a solution to make sure I don't have copies of data?
By Ram Prakash
Can anyone please tell what a DVR [ Data value reference ] is ? I want to know at what situation it will be used and what are the advantages we get by using DVR. I am really confused in this topic . If someone has any code in which they have worked with DVRs. kindly share it to me.