I have never been thrilled with the waveform data type, although it does
make some things easier. Part of my gripe is the time-stamping: If I'm
acquiring 1.0 second of data at 10000 samples/sec, I do *not* want my time
values represented as D/M/Y H:M:S.xx. I suspect there may be ways of
customising that format, but they are never obvious when I'm coding
something. Why can't you easily force it to default to milliseconds?

If I'm doing time based calculations (such as obtain the Y reading .25
seconds after a trigger event has been detected, where trigger is on a
seperate analog channel) I find that forcing t0 to 0.0 (using a  constant)
helps my numbers to come out right. 

Something else I usually do when I get tired of the conditions imposed on me
by the waveform type is to build a 2D array with X and Y as columns (or as
many Y columns as I have channels). You can easily build your X column in a
loop using the dt property of the waveform (which seems to default to
seconds). This may be the solution for your Matlab problem (I am not
familiar with Matlab syntax or data).   

It seems that even after the hysteria of Y2K time stamps and time stamp
formats still cause people grief. I think a lot more LabVIEW applications
acquire data over a span of seconds rather than weeks or days and I don't
feel the waveform data type has been well implemented in that respect. Those
list readers who know better are invited to correct me. :)

Johann Junginger.



-----Original Message-----
From: Thomas Gary [mailto:[EMAIL PROTECTED]
Sent: Tuesday, January 20, 2004 16:29
To: Info-LabVIEW
Subject: Question Refined...


Wireworkers,

With more investigation... I've found that my t0 variable on the Build
Waveform VI is a Time Stamp. I've never used a time stamp with my academic
Matlab code, so my next question is how do I convert a time stamp into a
Real number, namely zero.

Gary L Thomas


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