Digital Waveform graph with a lot of samples

Hi,
I have to display in a Digital Waveform Graph a lot of data read from a file(2.000.000 of samples for 36 signals). If I read the file and I try to display all the data, the Vi became unusable. For example, to zoom a graph region, it may take 30-40 seconds, scroll is impossible ecc, ecc..
Apparently LV doesn't perform a decimation of points. In measurements studio 8, this problem doesn't exist...but I have to use LV 7.1..
any suggestion ?
At the moment I have developed a DLL in VC++ that perform a decimation of samples, but performance are not very good !
Thank you for any idea.
Regards.

Hi Garraty,
Excuse me but I have several questions for you.
1)     Have you tried some kind of incremental approach, starting from 1 waveform and increasing towards 36? Do you experience some kind of on/off degeneration between, les’s say, 34 and 35 waveforms?
2)     How can you decimate a digital pseudorandom sequence of 2M samples without loosing information?
3)     Is this 2M samples an unavoidable constraint for your application?. Actually, it seems very difficult to extract some kind of visual information from a pseudorandom pattern of this length?
Thank you very much.
Kind Regards
FiloP
FiloP
It doesn't matter how beautiful your theory is, it doesn't matter how smart you are. If it doesn't agree with experiment, it's wrong.
Richard P. Feynman

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