X ^ A
A product of varieties is equipped with canonical projection maps onto it factors. Given a product of normal toric varieties and a nonempty array, this methods provides a concise way to make these toric maps.
The product of two normal toric varieties has projections onto each factor.
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If A indexes all the factors, then we simply obtain the identity map on X.
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When there are more than two factors, we also obtain projections onto any subset of the factors.
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When the normal toric variety is not constructed as a product, this method only reproduces the identity map.
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When the normal toric variety X is a blow-up and the array A is empty, one obtains the canonical projection.
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