Allan Gilmour

Ah, it is a single profile, sim.4 has 4 columns: x,y,z,iabs -> iabs stands for intensity, absolute. =) 

I actually selected it from the profiles button on the right and that is how it appeared in the expression. If I remove 'iabs', I get an error "argument 2 is invalid", but if remove 'sim.4', the error remains as "invalid syntax. Perhaps you forgot a comma?" =/