How to reduce the amount of data stored within a 2D array?

[FReich]

Hello everybody.

I am using LabView 8,2 and programming vibration measurement applications for PDAs.

The Problem is, that the PDA slows down too much, when displaying the aquired data.

To increase the speed, I want to reduce the displayed data of the 2D array.

I would like to display only every third or XX value of this array.

Many thanks

Franziskus

[daveTW]

Hi Franziskus,
you can use "decimate 1D array" in the array-palette.
Greets, Dave

[FReich]

Thank you,

I didnt know its that easy.

[DFGray]

How is your 2D array being displayed?  If it is as several traces on a graph, consider max-min decimate to get much better output results (example is for 1D array).  You can find examples of this at the beginning of the tutorial Managing Large Data Sets in LabVIEW.  You may want to read the tutorial, anyway, since almost all data is large on a PDA.  If it is as an image, you may want to check out some of the forum posts on rescaling images.  Simple decimation is fast, but the results are usually less than satisfactory unless you know you have smooth data.  Depending on your platform, you may be able to find some open source code to help you out.

Good luck.  Let us know if you need more help.

[FReich]

Thank you for your answere,

yeah the tutorial is great.

Do you know if there is a possiblility to reduce the ADC resolution of my DAQ Card.

I am using NI CF-6004 which has an resolution of 14 bits. For my current measurements thats a little high.

I guess, that if I gain data with just 10 bits that this would speed things up.

Yours

Franziskus