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We appreciate your patience as we improve our online experience.
06-18-2009 06:22 AM
Hi everyone,
I have a following problem. I have large binary files with measurement data. I'm making some kind of offline analysis - I must be able to play and analyses my waveform, control speed of plotting, start from specified position on record and change X scale range. I'm doing FFT analysis, Zoom FFT, Integration and many more. My program runs in while loop so I'm sending data in blocks. The problem is if I send , for example,1 second of data to Integration vi, I will get some kind of transient on the beginning of waveform for every block. I try to hide that part of waveform (offset on chars), but this make further analysis little bit too complex. I'm doing also an online analysis.
Is there any advised technique for this type of problem ? Running analysis on whole data is not an option. I have some ideas but they are not so much elegant. So I would like to hear some suggestions.
Thanks,
Tomislav
06-18-2009 10:25 AM
06-18-2009 02:55 PM
06-18-2009 03:09 PM
06-18-2009 03:32 PM
All filters also analog has something called setting time. So then you read your first block of data you will have some artifacts anyway. With some tricks you may remove this also. But as a starter set the init/cont Boolean to true, all time. Then you read the first data block will have artifacts the rest not. But this again depends on several other settings. But without going to deep into theory try this first
06-18-2009 04:04 PM
Great, that solve that problem. I have much bigger problem with blocks like SVL Integration.vi (see Attachment). I'dont have init/cont Boolean control and this block affects on all my further analysis. I would attach print screen or my VI but it is very large, so one more time:
1. SVL Integration block is inside while loop
2. I send data in blocks of variable length as 1-D array of waveform
3. data are read from file or from physical channel
Is it even possible to do this inside while loop without using additional number of samples and discarding them after analysis ?