decompose curve into eff and tangent class SISE9JRW

decompose curve into eff and tangent class

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Proposition 3.5. Let F be a toric foliation on a Q-factorial toric variety X. Let C be a curve in X such that KF · C < 0. Then [C] = [M ] + α where M is a torus invariant curve tangent to the foliation and α is a pseudo-effective class. (pdf) (Wang, 2023, p. 82)