how to rescale raster data values

Discussion created by cjwinings on Mar 6, 2012
I used "composite bands" to create a stacked image with ndvi as 1 band and a dem as another band. I'd like to classify the stacked image, and have tried, but the dem seems to be the only band that influences the classification. I am thinking this is because the ndvi values have such a small range (-1 to 1) compared to the dem (300-2000). Does anyone know how to rescale my ndvi data to have a similar range as my dem? Or do you have any ideas about why else this might be happening?