Well, the way I achieve that is to take say 16 ADC readings, sort them in sequential order of value, junk the top and bottom four readings as being 'out-of-range', sum and average the middle eight... this makes ADC readings in industrial applications pretty much bomb-proof...
Miss Melanie, in doing so you are potentially junking good data, but you can also potentially retain and use in your mean bad data, since you have no way to know how many bad readings you will take with your sampling.
A statistically correct approch should be to calculate the mean and the standard deviation (sd), of all your 16 readings, than retain all data within +/- 1 or 2 sd depending esclusively on your need.
A simpler approach could be to decide which threshold (in percentage of the mean) to apply to reduce the variance, than take the mean of all the 16 readings and discard all the data beyond the threshold limit.
In both cases you will not need to sort your array.
Al.
Last edited by aratti; - 8th November 2009 at 16:53.
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