direction
above &
below &
Define a region in 2 dimensions. This definition results in a logical which is TRUE if the combination of the values of the 2 variables is on the right side of the given polynomial, which is either ABOVE or BELOW. Again variables can be scalars or arrays.
Example:
/Define/cut/2d spec_e.ph_tg/spec_e.th_tg above 0.,1.,0.