How to remove noisy data points read from a text file

[Joe94]

Reading data measurements taken in from a txt file.  How do I get rid of noise aside from going into the text file and deciding point by point what to delete.

[egraham]

Well going in point by point and deleting is certainly one way of going about it. Of course that would defeat the entire purpose of having this great programming enviroment that is capable of doing that kind of thing for us.

Is your text file small enough to upload? Obviously you know what the criteria are for judging whether or not a data point is acceptable so it should be simple enough to program. Give us a bit more information and I can assure you there will be a race between LabVIEW experts to see who can post the cleanest, simplest, and fastest piece of code that will do what you need. My wager is on altenbach, but there are a few others here that are almost as impressive.

[Kyle_M]

Joe,

Labview has a number of ways to filter data. You can use signal processing methods like noise filters, you can sample at a higher rate, then average groups of data, you can simply disregard points out of a range, etc.

If you have the disqualifying criteria, Im sure the fellows here will snap at the opportunity to outdo eachother for code quality.

Regards,

Kyle Mozdzyn

Applications Engineering

National Instruments

[falkpl]

Median filters work well for throwing out outliers.  new data is equal the the median on a group of points about the original point, for random noise points, 3point media can do the trick, what does the data look like.