Implementing subschemes functionality for projective "is_morphism"

[sagetrac-jdefaria]

Changing the projective "is_morphism" to work over subschemes

Component: algebraic geometry

Author: Joao Alberto de Faria

Branch: f9ce9da

Reviewer: Ben Hutz

Issue created by migration from https://trac.sagemath.org/ticket/17326

[sagetrac-jdefaria]

Author: jdefaria

[sagetrac-jdefaria]

Branch: u/jdefaria/ticket/17326

[sagetrac-jdefaria]

Commit: 964c524

[sagetrac-jdefaria]

New commits:

964c524

Added functionality and example for subschemes

[bhutz]

comment:4

You don't need this check since if it is a projective morphism it must be some kind of projective scheme.

if is_ProjectiveSpace(self.domain().ambient_space()) is False or is_ProjectiveSpace(self.codomain().ambient_space()) is False:

[bhutz]

Reviewer: Ben Hutz

[sagetrac-jdefaria]

Changed author from jdefaria to Joao Alberto de Faria

[sagetrac-git]

Changed commit from 964c524 to 58fa66d

[sagetrac-git]

Branch pushed to git repo; I updated commit sha1. New commits:

58fa66d

Rewrote main functionality, should work now

[sagetrac-git]

Changed commit from 58fa66d to 4adf3c9

[sagetrac-git]

Branch pushed to git repo; I updated commit sha1. New commits:

4adf3c9

-17326- cleaned up cod, and fixed minor coerce issue

[bhutz]

comment:9

Sorry to be picky, but I'd like a subscheme example that fails to be a morphism on projective space, but which is a morphism for a subscheme, ie., the indeterminancy locus does not intersect the subscheme. The example you give is already a morphism on projective space.

Otherwise, this looks fine.

[sagetrac-git]

Changed commit from 4adf3c9 to f9ce9da

[sagetrac-git]

Branch pushed to git repo; I updated commit sha1. New commits:

f9ce9da

-17326- Added example

[bhutz]

comment:12

ok, this looks good now.

[vbraun]

Changed branch from u/jdefaria/ticket/17326 to f9ce9da

[sagetrac-jdefaria]

Changed commit from f9ce9da to none