Proof. [02SD]
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Proof.
Let be a semipositive toric model. By Theorem 4.81, to the pair corresponds a pair , where is an H-lattice function on , and . By Theorem 4.95, the function is concave. We put . It is clear that equivalent models produce the same function.
Conversely, let be a rational piecewise affine concave function. Let . This is a rational polyhedral complex. Let . This is a conic rational polyhedral complex. By Proposition 3.72, . Since is a support function on , we deduce that is a refinement of . Put (Definition 3.10). Since is a rational polyhedral complex and is a fan, then is an SCR polyhedral complex. Moreover, by Lemma 3.11, we have
Let be an integer such that is an H-lattice function. Then is a toric model of . Both procedures are inverse of each other. ∎