I have done the following procedure which has resulted in a troubling behavior:
I have a Shapefile Feature Class with multiple different areas under specific distinct description field. I need to make a supervised classification and construct a training sample from e.g, 10 samples to 1 class.
By querying I have made as many Feature Classes as there are different descriptions. Then in order not to make 10 polygons for each one, I have extracted them as Shapefiles (X_description.shp) which are fine indeed on the map.
Then I open the Training Sample Manager which allows me to Load Training Samples and I open a Shapefile, delete all but 10 sample ROIs and try to merge them in one class.
And here is the issue : ArcGIS does not respond to "Merge Training Samples" at all.
However when I draw polygons it is just fine.
Does anyone have an idea why this happens and how to overcome it in order NOT to make hundreds of polygons manually?