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RationalMap _* -- direct image via a rational map

Operator: _*
Usage:

phi_* I
Inputs:
- phi, a rational map, I a homogeneous ideal in the coordinate ring of the source of phi
Outputs:
- an ideal, the ideal of the closure of the direct image of V(I) via phi

Description

In most cases this is equivalent to phi I, which is faster but may not take into account other representations of the map.

See also

RationalMap ^** Ideal -- inverse image via a rational map
source(RationalMap) -- coordinate ring of the source for a rational map

Ways to use this method:

RationalMap _* -- direct image via a rational map

The source of this document is in /build/macaulay2-88fgJW/macaulay2-1.25.11+ds/M2/Macaulay2/packages/Cremona/documentation.m2:383:0.