I computed Enhanced Vegetation Index using band math in ENVI 4.7 software. The expression used was:
2.5*((float(b1)- float(b2))/(float(b1)+ (6*float(b2)) +(7.5* float(b3)))) BYTSCL(float(b1), min = -1.0, max = 1.0)
The output EVI file has values varying from 0 to 255 rather than -1 to +1. Can anyone suggest an edit to the expression or a method.