How to use a Time - Voltage Array to Control a Analog Voltage Output using DAQmx Write VI

I have an array of Time values associate with Voltage values that I want to use to control a Anolog Votage Out Device (PXI-6251) using DAQmx. The array contains 1,000 elements. The time values are NOT evenly spaced, the rate changes through the array. The array is output once, timed to other processes.
My problem is I haven't been able to locate a reference on how to handle the timing variability in the array. If time was equally spaced I could use a loop....
The attached showes the array, first row is time (ms) and the second row is voltage (volts).
Can someone point me in the right direction?
David
Attachments:
TimeVoltage.png ‏11 KB

David,
if you have only Base version of LabVIEW, this will be a time consuming task.
If you have either Full or Professional, you will find interpolation-functions in the mathematic palette.
I am not sure which ones serves you best, but i'd startexperimenting with Interpolate 2D.
hope this helps,
Norbert
[Edit]: You could also use a polynominal fit on your voltage values. You will get a function describing the voltage over time. But you will have to modify this function to take care of the variation of time spacing. If you have a function describing your voltage over your (nonconstant) timestamps, you can simply create values for constant timeslices for your voltage.
Message Edited by Norbert B on 11-06-2008 10:21 AM
CEO: What exactly is stopping us from doing this?
Expert: Geometry
Marketing Manager: Just ignore it.

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"nelsons" wrote in message
news:[email protected]...
> how do I create a 1d array that takes a single calculation and insert
> the result into the first row and then the next calculation the next
> time the loop passes that point and puts the results in thsecond row
> and so on until the loop is exited.
>
> The attached file is work inprogress, with some dummy data sp that I
> can test it out without having to connect to equipment.
> The second tab is the one that I am having the problem with. the
> output array from the replace element appears to be starting at the
> index position of 1 rather than 0 but that is ok it is still show that
> the new data is placed in incrementing element locations. However the
> main array that I am trying to build that is suppose to take each new
> calculation and place it in the next index(row) does not appear to be
> working or at least I am not getting any indication on the inidcator.
>
> Basically what I am attempting to do is is gather some pulses from
> adevice for a minute, place the results for a calculation, so that it
> displays then do the same again the next minute, but put these result
> in the next row and so on until the specifiied time has expired and
> the loop exits. I need to have all results displayed and keep building
> the array(display until, the end of the test)Eventually I will have to
> include a min max section that displays the min and max values
> calculated, but that should be easy with the min max function.Actually
> I thought this should have been easy but, I gues I can not see the
> forest through the trees. Can any one help to slear this up for me.

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How to use a Time - Voltage Array to Control a Analog Voltage Output using DAQmx Write VI

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