Hello, I'm new to ENVI and have a question about classifications: I need to run some stats on various classifications of vegetation data. I can easily do this with the ENVI supervised and unsupervised classifications but am having trouble with Jenks/natural breaks. I've tried using a decision tree with ArcGIS-generated natural break values, but because the ENVI-generated masked image cannot have "nodata" mask value and needs a defined value, the Arc Jenks distribution is being skewed and I cannot use them. Can I make a no-value in ENVI? Or better yet, how can I simply run a Jenks classification in ENVI to avoid going to Arc? Any ideas? Thank you