1. A method comprising: identifying ( 78 ) a target simplex (T 7 ) from simplices having points in a device independent space, each point having a corresponding combination of device dependent inputs ( 54 , 56 , 58 ), the identifying comprising: determining ( 76 ) whether a test simplex contains a target result (TR) in the device independent space, wherein if the test simplex does not contain the target result, selecting another adjacent simplex as the test simplex and repeating the determining until the target simplex (T 7 ) is identified ( 77 ); and interpolating ( 80 ) the device dependent inputs of the points ( 214 , 216 , 218 ) of the target simplex (T 7 ) to identify a combination of device dependent inputs for the target result (TR).