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image(RationalMap,ZZ) -- closure of the image of a rational map

Function: image
Usage:

image Phi

image(Phi,d)
Inputs:
- Phi, a rational map
- d, an integer
Outputs:
- an ideal, the ideal defining the closure of the image of Phi, or its degree d homogeneous component if d is passed

Description

This computation is done through the kernel of a ring map representing the rational map. See kernel(RingMap) and kernel(RingMap,ZZ) for more details.

See also

kernel(RingMap,ZZ)
kernel(RingMap) -- kernel of a ringmap
image(RationalMap,String) -- closure of the image of a rational map using the F4 algorithm (experimental)

Ways to use this method:

image(RationalMap)
image(RationalMap,ZZ) -- closure of the image of a rational map

The source of this document is in Cremona/documentation.m2:672:0.