An Iitaka fibration of a divisor of nonnegative Iitaka dimension is the rational fibration determined
by its section-ratio field. For a rational Cartier
divisor 
on a normal integral projective variety over
, let
 |
where the floor function rounds each divisor coefficient down and the divisorial sheaf is reflexive. The Iitaka
field 
is generated by ratios of nonzero sections
from the same 
, over all positive integers 
with 
. In sufficiently large
divisible degrees, the image of the complete system has this function
field. Its dimension is 
.
