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Enable Binder environment for PRs #36245

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@kwankyu kwankyu commented Sep 11, 2023

Solves sagemath/sage-binder-env#3, but now on GitHub platform.

The author of a PR can use (workflow-dispatch) "Create Binder branch" workflow in her own forked repo to create a new branch "contribution-binder" for a PR branch "contribution". Then she can post the new "contribution-binder" branch or just the Binder badge on the PR description. The reviewers can click the Binder badge to open the Binder environment to test the Sage built with the PR.

Specifically the procedure is
(1) Go to your forked Sage repo
(2) In the Actions tab, find "Create Binder branch" workflow
(3) Run the workflow with your PR branch named say "contribution"
(4) Wait for the workflow run to finish
(5) In the Code tab, select the new "contribution-binder" branch
(6) Edit the generated Dockerfile as you need (and commit)
(7) Find the Binder badge in README.md
(8) Copy the Binder badge from README.md (in edit mode)
(9) Paste the Binder badge into the description of your PR in the sagemath/sage repo
(10) Click the Binder badge to start creating the Binder environment
(11) Leave it open and come back after an hour.
(12) The Binder badge is now ready for reviewers of your PR

The Binder environment branch has Dockerfile, README.md, and a directory notebooks. The Dockerfile builds Sage incrementally with the PR branch. The README.md is the official Sage readme file, but has the Binder badge. The notebooks directory can be used to put some testing Jupyter notebooks provided by the PR author. The notebooks are available in the invoked JupyterLab.

The PR author is supposed to run the Binder badge once so that Binder builds the Docker image. This step takes the longest time, but reasonably fast as it is incremental build. Subsequent runs of the Binder badge take much less time.

For example, this

https://github.com/kwankyu/sage/tree/p/binder-enabled-repo-binder

is the Binder environment branch for this PR. Note that -binder is suffixed to the PR branch p/binder-enabled-repo, and this is the Binder badge

Binder

for the Binder environment built with this PR branch. This badge is taken from the README.md file of the above Binder environment branch.

📝 Checklist

  • The title is concise, informative, and self-explanatory.
  • The description explains in detail what this PR is about.
  • I have linked a relevant issue or discussion.
  • I have created tests covering the changes.
  • I have updated the documentation accordingly.

⌛ Dependencies

@kwankyu kwankyu force-pushed the p/binder-enabled-repo branch 2 times, most recently from 547dee1 to 5930e3d Compare September 15, 2023 06:12
@kwankyu kwankyu force-pushed the p/binder-enabled-repo branch 5 times, most recently from 8bc5b18 to cd97a1b Compare December 2, 2023 10:50
@kwankyu kwankyu mentioned this pull request Dec 4, 2023
5 tasks
@kwankyu kwankyu marked this pull request as ready for review December 4, 2023 04:43
vbraun pushed a commit to vbraun/sage that referenced this pull request Dec 10, 2023
    
<!-- ^^^^^
Please provide a concise, informative and self-explanatory title.
Don't put issue numbers in there, do this in the PR body below.
For example, instead of "Fixes sagemath#1234" use "Introduce new method to
calculate 1+1"
-->
<!-- Describe your changes here in detail -->

for those who want to play with Sage instantly, and also as a
preparation for sagemath#36245.

See this [REAME.md](https://github.com/kwankyu/sage/tree/p/add-binder-
badge-to-readme).

<!-- Why is this change required? What problem does it solve? -->
<!-- If this PR resolves an open issue, please link to it here. For
example "Fixes sagemath#12345". -->
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### 📝 Checklist

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<!-- If your change requires a documentation PR, please link it
appropriately -->
<!-- If you're unsure about any of these, don't hesitate to ask. We're
here to help! -->
<!-- Feel free to remove irrelevant items. -->

- [x] The title is concise, informative, and self-explanatory.
- [x] The description explains in detail what this PR is about.
- [x] I have linked a relevant issue or discussion.
- [ ] I have created tests covering the changes.
- [ ] I have updated the documentation accordingly.

### ⌛ Dependencies

<!-- List all open PRs that this PR logically depends on
- sagemath#12345: short description why this is a dependency
- sagemath#34567: ...
-->

<!-- If you're unsure about any of these, don't hesitate to ask. We're
here to help! -->
    
URL: sagemath#36815
Reported by: Kwankyu Lee
Reviewer(s): Matthias Köppe
vbraun pushed a commit to vbraun/sage that referenced this pull request Dec 13, 2023
    
<!-- ^^^^^
Please provide a concise, informative and self-explanatory title.
Don't put issue numbers in there, do this in the PR body below.
For example, instead of "Fixes sagemath#1234" use "Introduce new method to
calculate 1+1"
-->
<!-- Describe your changes here in detail -->

for those who want to play with Sage instantly, and also as a
preparation for sagemath#36245.

See this [REAME.md](https://github.com/kwankyu/sage/tree/p/add-binder-
badge-to-readme).

<!-- Why is this change required? What problem does it solve? -->
<!-- If this PR resolves an open issue, please link to it here. For
example "Fixes sagemath#12345". -->
<!-- If your change requires a documentation PR, please link it
appropriately. -->

### 📝 Checklist

<!-- Put an `x` in all the boxes that apply. -->
<!-- If your change requires a documentation PR, please link it
appropriately -->
<!-- If you're unsure about any of these, don't hesitate to ask. We're
here to help! -->
<!-- Feel free to remove irrelevant items. -->

- [x] The title is concise, informative, and self-explanatory.
- [x] The description explains in detail what this PR is about.
- [x] I have linked a relevant issue or discussion.
- [ ] I have created tests covering the changes.
- [ ] I have updated the documentation accordingly.

### ⌛ Dependencies

<!-- List all open PRs that this PR logically depends on
- sagemath#12345: short description why this is a dependency
- sagemath#34567: ...
-->

<!-- If you're unsure about any of these, don't hesitate to ask. We're
here to help! -->
    
URL: sagemath#36815
Reported by: Kwankyu Lee
Reviewer(s): Matthias Köppe
@kwankyu kwankyu force-pushed the p/binder-enabled-repo branch 2 times, most recently from 8d4f219 to ee50dc0 Compare December 16, 2023 22:56
@kwankyu kwankyu force-pushed the p/binder-enabled-repo branch 6 times, most recently from 11dfcd7 to 4e558f9 Compare December 18, 2023 10:33
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Documentation preview for this PR (built with commit 3a05362; changes) is ready! 🎉
This preview will update shortly after each push to this PR.

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mkoeppe commented Mar 11, 2024

The branches that this creates -- they do not contain the Sage sources, correct?

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kwankyu commented Mar 11, 2024

No. It adds a Dockerfile and a directory notebooks to the sage source, and and modifies README.md.

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kwankyu commented Mar 11, 2024

It creates a branch of the PR branch in origin, the forked repository.

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kwankyu commented Mar 11, 2024

A recent example is in #35467

vbraun pushed a commit to vbraun/sage that referenced this pull request Apr 17, 2024
    
<!-- Please provide a concise, informative and self-explanatory title.
-->
<!-- Don't put issue numbers in the title. Put it in the Description
below. -->
<!-- For example, instead of "Fixes sagemath#12345", use "Add a new method to
multiply two integers" -->

### 📚 Description

We attach Jacobians to function fields and curves, enabling arithmetic
with the points of the Jacobian. Fixes sagemath#34232.

A point of Jacobian is represented by an effective divisor `D` such that
the point is the divisor class of `D - B` (of degree 0) with a fixed
base divisor `B`.

There are two models for Jacobian arithmetic:

- Hess model:  `D` is internally represented by a pair of certain ideals
and arithmetic relies on divisor reduction using Riemann-Roch space
computation by Hess' algorithm.
- Khuri-Makdisi model: `D` is internally represented by a linear
subspace `W_D` of a linear space `V` and arithmetic uses Khuri-Makdisi's
linear algebra algorithms. For implementation, sagemath#15113 was referenced.


An example with non-hyperelliptic genus 3 curve:
```sage
sage: A2.<x,y> = AffineSpace(QQ, 2)
sage: f = y^3 + x^4 - 5*x^2*y + 2*x*y - x^2 - 5*y - 4*x + 1
sage: C = Curve(f, A2)
sage: X = C.projective_closure()
sage: X.genus()
3
sage: X.rational_points(bound=5)
[(0 : 0 : 1), (1/3 : 1/3 : 1)]
sage: Q = X(0,0,1).place()
sage: P = X(1,1,3).place()
sage: D = P - Q
sage: D.degree()
0
sage: J = X.jacobian(model='hess', base_div=3*Q)
sage: G = J.group()
sage: p = G.point(D)
sage: 2*p + 3*p == 5*p
True
```

An example with elliptic curve:
```sage
sage: k.<a> = GF((5,2))
sage: E = EllipticCurve(k,[1,0]); E
Elliptic Curve defined by y^2 = x^3 + x over Finite Field in a of size
5^2
sage: E.order()
32
sage: P = E([a, 2*a + 4])
sage: P
(a : 2*a + 4 : 1)
sage: P.order()
8
sage: p = P.point_of_jacobian_of_curve()
sage: p
[Place (x + 4*a, y + 3*a + 1)]
sage: p.order()
8
sage: Q = 3*P
sage: q = Q.point_of_jacobian_of_curve()
sage: q == 3*p
True
sage: G = p.parent()
sage: G.order()
32
sage: G
Group of rational points of Jacobian over Finite Field in a of size 5^2
(Hess model)
sage: J = G.parent(); J
Jacobian of Projective Plane Curve over Finite Field in a of size 5^2
 defined by x^2*y + y^3 - x*z^2 (Hess model)
sage: J.curve() == E.affine_patch(2).projective_closure()
True
```

An example with hyperelliptic curve:
```sage
sage: R.<x> = PolynomialRing(GF(11))
sage: f = x^6 + x + 1
sage: H = HyperellipticCurve(f)
sage: J = H.jacobian()
sage: D = J(H.lift_x(1))
sage: D  # divisor in Mumford representation
(x + 10, y + 6)
sage: jacobian_order = sum(H.frobenius_polynomial())
sage: jacobian_order
234
sage: p = D.point_of_jacobian_of_curve(); p
sage: p  # Jacobian point represented by an effective divisor
[Place (1/x0, 1/x0^3*x1 + 1)
 + Place (x0 + 10, x1 + 6)]
sage: p.order()
39
sage: 234*p == 0
True
sage: G = p.parent()
sage: G
Group of rational points of Jacobian over Finite Field of size 11 (Hess
model)
sage: J = G.parent()
sage: J
Jacobian of Projective Plane Curve over Finite Field of size 11
 defined by x0^6 + x0^5*x1 + x1^6 - x0^4*x2^2 (Hess model)
sage: C = J.curve()
sage: C
Projective Plane Curve over Finite Field of size 11
 defined by x0^6 + x0^5*x1 + x1^6 - x0^4*x2^2
sage: C.affine_patch(0) == H.affine_patch(2)
True
```

[![Binder](https://mybinder.org/badge_logo.svg)](https://mybinder.org/v2
/gh/kwankyu/sage/p/35467/add-jacobian-groups-notebook-binder) prepared
with sagemath#36245

<!-- Describe your changes here in detail. -->
<!-- Why is this change required? What problem does it solve? -->
<!-- If this PR resolves an open issue, please link to it here. For
example "Fixes sagemath#12345". -->
<!-- If your change requires a documentation PR, please link it
appropriately. -->

### 📝 Checklist

<!-- Put an `x` in all the boxes that apply. It should be `[x]` not `[x
]`. -->

- [x] The title is concise, informative, and self-explanatory.
- [x] The description explains in detail what this PR is about.
- [x] I have linked a relevant issue or discussion.
- [x] I have created tests covering the changes.
- [x] I have updated the documentation accordingly.

### ⌛ Dependencies

<!-- List all open PRs that this PR logically depends on
- sagemath#12345: short description why this is a dependency
- sagemath#34567: ...
-->

<!-- If you're unsure about any of these, don't hesitate to ask. We're
here to help! -->
    
URL: sagemath#35467
Reported by: Kwankyu Lee
Reviewer(s): Kwankyu Lee, Matthias Köppe
vbraun pushed a commit to vbraun/sage that referenced this pull request Apr 17, 2024
<!-- Please provide a concise, informative and self-explanatory title.
-->
<!-- Don't put issue numbers in the title. Put it in the Description
below. -->
<!-- For example, instead of "Fixes sagemath#12345", use "Add a new method to
multiply two integers" -->

### 📚 Description

We attach Jacobians to function fields and curves, enabling arithmetic
with the points of the Jacobian. Fixes sagemath#34232.

A point of Jacobian is represented by an effective divisor `D` such that
the point is the divisor class of `D - B` (of degree 0) with a fixed
base divisor `B`.

There are two models for Jacobian arithmetic:

- Hess model:  `D` is internally represented by a pair of certain ideals
and arithmetic relies on divisor reduction using Riemann-Roch space
computation by Hess' algorithm.
- Khuri-Makdisi model: `D` is internally represented by a linear
subspace `W_D` of a linear space `V` and arithmetic uses Khuri-Makdisi's
linear algebra algorithms. For implementation, sagemath#15113 was referenced.

An example with non-hyperelliptic genus 3 curve:
```sage
sage: A2.<x,y> = AffineSpace(QQ, 2)
sage: f = y^3 + x^4 - 5*x^2*y + 2*x*y - x^2 - 5*y - 4*x + 1
sage: C = Curve(f, A2)
sage: X = C.projective_closure()
sage: X.genus()
3
sage: X.rational_points(bound=5)
[(0 : 0 : 1), (1/3 : 1/3 : 1)]
sage: Q = X(0,0,1).place()
sage: P = X(1,1,3).place()
sage: D = P - Q
sage: D.degree()
0
sage: J = X.jacobian(model='hess', base_div=3*Q)
sage: G = J.group()
sage: p = G.point(D)
sage: 2*p + 3*p == 5*p
True
```

An example with elliptic curve:
```sage
sage: k.<a> = GF((5,2))
sage: E = EllipticCurve(k,[1,0]); E
Elliptic Curve defined by y^2 = x^3 + x over Finite Field in a of size
5^2
sage: E.order()
32
sage: P = E([a, 2*a + 4])
sage: P
(a : 2*a + 4 : 1)
sage: P.order()
8
sage: p = P.point_of_jacobian_of_curve()
sage: p
[Place (x + 4*a, y + 3*a + 1)]
sage: p.order()
8
sage: Q = 3*P
sage: q = Q.point_of_jacobian_of_curve()
sage: q == 3*p
True
sage: G = p.parent()
sage: G.order()
32
sage: G
Group of rational points of Jacobian over Finite Field in a of size 5^2
(Hess model)
sage: J = G.parent(); J
Jacobian of Projective Plane Curve over Finite Field in a of size 5^2
 defined by x^2*y + y^3 - x*z^2 (Hess model)
sage: J.curve() == E.affine_patch(2).projective_closure()
True
```

An example with hyperelliptic curve:
```sage
sage: R.<x> = PolynomialRing(GF(11))
sage: f = x^6 + x + 1
sage: H = HyperellipticCurve(f)
sage: J = H.jacobian()
sage: D = J(H.lift_x(1))
sage: D  # divisor in Mumford representation
(x + 10, y + 6)
sage: jacobian_order = sum(H.frobenius_polynomial())
sage: jacobian_order
234
sage: p = D.point_of_jacobian_of_curve(); p
sage: p  # Jacobian point represented by an effective divisor
[Place (1/x0, 1/x0^3*x1 + 1)
 + Place (x0 + 10, x1 + 6)]
sage: p.order()
39
sage: 234*p == 0
True
sage: G = p.parent()
sage: G
Group of rational points of Jacobian over Finite Field of size 11 (Hess
model)
sage: J = G.parent()
sage: J
Jacobian of Projective Plane Curve over Finite Field of size 11
 defined by x0^6 + x0^5*x1 + x1^6 - x0^4*x2^2 (Hess model)
sage: C = J.curve()
sage: C
Projective Plane Curve over Finite Field of size 11
 defined by x0^6 + x0^5*x1 + x1^6 - x0^4*x2^2
sage: C.affine_patch(0) == H.affine_patch(2)
True
```

[![Binder](https://mybinder.org/badge_logo.svg)](https://mybinder.org/v2
/gh/kwankyu/sage/p/35467/add-jacobian-groups-notebook-binder) prepared
with sagemath#36245

<!-- Describe your changes here in detail. -->
<!-- Why is this change required? What problem does it solve? -->
<!-- If this PR resolves an open issue, please link to it here. For
example "Fixes sagemath#12345". -->
<!-- If your change requires a documentation PR, please link it
appropriately. -->

### 📝 Checklist

<!-- Put an `x` in all the boxes that apply. It should be `[x]` not `[x
]`. -->

- [x] The title is concise, informative, and self-explanatory.
- [x] The description explains in detail what this PR is about.
- [x] I have linked a relevant issue or discussion.
- [x] I have created tests covering the changes.
- [x] I have updated the documentation accordingly.

### ⌛ Dependencies

<!-- List all open PRs that this PR logically depends on
- sagemath#12345: short description why this is a dependency
- sagemath#34567: ...
-->

<!-- If you're unsure about any of these, don't hesitate to ask. We're
here to help! -->

URL: sagemath#35467
Reported by: Kwankyu Lee
Reviewer(s): Kwankyu Lee, Matthias Köppe
vbraun pushed a commit to vbraun/sage that referenced this pull request Apr 18, 2024
    
<!-- Please provide a concise, informative and self-explanatory title.
-->
<!-- Don't put issue numbers in the title. Put it in the Description
below. -->
<!-- For example, instead of "Fixes sagemath#12345", use "Add a new method to
multiply two integers" -->

### 📚 Description

We attach Jacobians to function fields and curves, enabling arithmetic
with the points of the Jacobian. Fixes sagemath#34232.

A point of Jacobian is represented by an effective divisor `D` such that
the point is the divisor class of `D - B` (of degree 0) with a fixed
base divisor `B`.

There are two models for Jacobian arithmetic:

- Hess model:  `D` is internally represented by a pair of certain ideals
and arithmetic relies on divisor reduction using Riemann-Roch space
computation by Hess' algorithm.
- Khuri-Makdisi model: `D` is internally represented by a linear
subspace `W_D` of a linear space `V` and arithmetic uses Khuri-Makdisi's
linear algebra algorithms. For implementation, sagemath#15113 was referenced.


An example with non-hyperelliptic genus 3 curve:
```sage
sage: A2.<x,y> = AffineSpace(QQ, 2)
sage: f = y^3 + x^4 - 5*x^2*y + 2*x*y - x^2 - 5*y - 4*x + 1
sage: C = Curve(f, A2)
sage: X = C.projective_closure()
sage: X.genus()
3
sage: X.rational_points(bound=5)
[(0 : 0 : 1), (1/3 : 1/3 : 1)]
sage: Q = X(0,0,1).place()
sage: P = X(1,1,3).place()
sage: D = P - Q
sage: D.degree()
0
sage: J = X.jacobian(model='hess', base_div=3*Q)
sage: G = J.group()
sage: p = G.point(D)
sage: 2*p + 3*p == 5*p
True
```

An example with elliptic curve:
```sage
sage: k.<a> = GF((5,2))
sage: E = EllipticCurve(k,[1,0]); E
Elliptic Curve defined by y^2 = x^3 + x over Finite Field in a of size
5^2
sage: E.order()
32
sage: P = E([a, 2*a + 4])
sage: P
(a : 2*a + 4 : 1)
sage: P.order()
8
sage: p = P.point_of_jacobian_of_curve()
sage: p
[Place (x + 4*a, y + 3*a + 1)]
sage: p.order()
8
sage: Q = 3*P
sage: q = Q.point_of_jacobian_of_curve()
sage: q == 3*p
True
sage: G = p.parent()
sage: G.order()
32
sage: G
Group of rational points of Jacobian over Finite Field in a of size 5^2
(Hess model)
sage: J = G.parent(); J
Jacobian of Projective Plane Curve over Finite Field in a of size 5^2
 defined by x^2*y + y^3 - x*z^2 (Hess model)
sage: J.curve() == E.affine_patch(2).projective_closure()
True
```

An example with hyperelliptic curve:
```sage
sage: R.<x> = PolynomialRing(GF(11))
sage: f = x^6 + x + 1
sage: H = HyperellipticCurve(f)
sage: J = H.jacobian()
sage: D = J(H.lift_x(1))
sage: D  # divisor in Mumford representation
(x + 10, y + 6)
sage: jacobian_order = sum(H.frobenius_polynomial())
sage: jacobian_order
234
sage: p = D.point_of_jacobian_of_curve(); p
sage: p  # Jacobian point represented by an effective divisor
[Place (1/x0, 1/x0^3*x1 + 1)
 + Place (x0 + 10, x1 + 6)]
sage: p.order()
39
sage: 234*p == 0
True
sage: G = p.parent()
sage: G
Group of rational points of Jacobian over Finite Field of size 11 (Hess
model)
sage: J = G.parent()
sage: J
Jacobian of Projective Plane Curve over Finite Field of size 11
 defined by x0^6 + x0^5*x1 + x1^6 - x0^4*x2^2 (Hess model)
sage: C = J.curve()
sage: C
Projective Plane Curve over Finite Field of size 11
 defined by x0^6 + x0^5*x1 + x1^6 - x0^4*x2^2
sage: C.affine_patch(0) == H.affine_patch(2)
True
```

[![Binder](https://mybinder.org/badge_logo.svg)](https://mybinder.org/v2
/gh/kwankyu/sage/p/35467/add-jacobian-groups-notebook-binder) prepared
with sagemath#36245

<!-- Describe your changes here in detail. -->
<!-- Why is this change required? What problem does it solve? -->
<!-- If this PR resolves an open issue, please link to it here. For
example "Fixes sagemath#12345". -->
<!-- If your change requires a documentation PR, please link it
appropriately. -->

### 📝 Checklist

<!-- Put an `x` in all the boxes that apply. It should be `[x]` not `[x
]`. -->

- [x] The title is concise, informative, and self-explanatory.
- [x] The description explains in detail what this PR is about.
- [x] I have linked a relevant issue or discussion.
- [x] I have created tests covering the changes.
- [x] I have updated the documentation accordingly.

### ⌛ Dependencies

<!-- List all open PRs that this PR logically depends on
- sagemath#12345: short description why this is a dependency
- sagemath#34567: ...
-->

<!-- If you're unsure about any of these, don't hesitate to ask. We're
here to help! -->
    
URL: sagemath#35467
Reported by: Kwankyu Lee
Reviewer(s): Kwankyu Lee, Matthias Köppe
vbraun pushed a commit to vbraun/sage that referenced this pull request Apr 20, 2024
    
<!-- Please provide a concise, informative and self-explanatory title.
-->
<!-- Don't put issue numbers in the title. Put it in the Description
below. -->
<!-- For example, instead of "Fixes sagemath#12345", use "Add a new method to
multiply two integers" -->

### 📚 Description

We attach Jacobians to function fields and curves, enabling arithmetic
with the points of the Jacobian. Fixes sagemath#34232.

A point of Jacobian is represented by an effective divisor `D` such that
the point is the divisor class of `D - B` (of degree 0) with a fixed
base divisor `B`.

There are two models for Jacobian arithmetic:

- Hess model:  `D` is internally represented by a pair of certain ideals
and arithmetic relies on divisor reduction using Riemann-Roch space
computation by Hess' algorithm.
- Khuri-Makdisi model: `D` is internally represented by a linear
subspace `W_D` of a linear space `V` and arithmetic uses Khuri-Makdisi's
linear algebra algorithms. For implementation, sagemath#15113 was referenced.


An example with non-hyperelliptic genus 3 curve:
```sage
sage: A2.<x,y> = AffineSpace(QQ, 2)
sage: f = y^3 + x^4 - 5*x^2*y + 2*x*y - x^2 - 5*y - 4*x + 1
sage: C = Curve(f, A2)
sage: X = C.projective_closure()
sage: X.genus()
3
sage: X.rational_points(bound=5)
[(0 : 0 : 1), (1/3 : 1/3 : 1)]
sage: Q = X(0,0,1).place()
sage: P = X(1,1,3).place()
sage: D = P - Q
sage: D.degree()
0
sage: J = X.jacobian(model='hess', base_div=3*Q)
sage: G = J.group()
sage: p = G.point(D)
sage: 2*p + 3*p == 5*p
True
```

An example with elliptic curve:
```sage
sage: k.<a> = GF((5,2))
sage: E = EllipticCurve(k,[1,0]); E
Elliptic Curve defined by y^2 = x^3 + x over Finite Field in a of size
5^2
sage: E.order()
32
sage: P = E([a, 2*a + 4])
sage: P
(a : 2*a + 4 : 1)
sage: P.order()
8
sage: p = P.point_of_jacobian_of_curve()
sage: p
[Place (x + 4*a, y + 3*a + 1)]
sage: p.order()
8
sage: Q = 3*P
sage: q = Q.point_of_jacobian_of_curve()
sage: q == 3*p
True
sage: G = p.parent()
sage: G.order()
32
sage: G
Group of rational points of Jacobian over Finite Field in a of size 5^2
(Hess model)
sage: J = G.parent(); J
Jacobian of Projective Plane Curve over Finite Field in a of size 5^2
 defined by x^2*y + y^3 - x*z^2 (Hess model)
sage: J.curve() == E.affine_patch(2).projective_closure()
True
```

An example with hyperelliptic curve:
```sage
sage: R.<x> = PolynomialRing(GF(11))
sage: f = x^6 + x + 1
sage: H = HyperellipticCurve(f)
sage: J = H.jacobian()
sage: D = J(H.lift_x(1))
sage: D  # divisor in Mumford representation
(x + 10, y + 6)
sage: jacobian_order = sum(H.frobenius_polynomial())
sage: jacobian_order
234
sage: p = D.point_of_jacobian_of_curve(); p
sage: p  # Jacobian point represented by an effective divisor
[Place (1/x0, 1/x0^3*x1 + 1)
 + Place (x0 + 10, x1 + 6)]
sage: p.order()
39
sage: 234*p == 0
True
sage: G = p.parent()
sage: G
Group of rational points of Jacobian over Finite Field of size 11 (Hess
model)
sage: J = G.parent()
sage: J
Jacobian of Projective Plane Curve over Finite Field of size 11
 defined by x0^6 + x0^5*x1 + x1^6 - x0^4*x2^2 (Hess model)
sage: C = J.curve()
sage: C
Projective Plane Curve over Finite Field of size 11
 defined by x0^6 + x0^5*x1 + x1^6 - x0^4*x2^2
sage: C.affine_patch(0) == H.affine_patch(2)
True
```

[![Binder](https://mybinder.org/badge_logo.svg)](https://mybinder.org/v2
/gh/kwankyu/sage/p/35467/add-jacobian-groups-notebook-binder) prepared
with sagemath#36245

<!-- Describe your changes here in detail. -->
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example "Fixes sagemath#12345". -->
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appropriately. -->

### 📝 Checklist

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]`. -->

- [x] The title is concise, informative, and self-explanatory.
- [x] The description explains in detail what this PR is about.
- [x] I have linked a relevant issue or discussion.
- [x] I have created tests covering the changes.
- [x] I have updated the documentation accordingly.

### ⌛ Dependencies

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- sagemath#12345: short description why this is a dependency
- sagemath#34567: ...
-->

<!-- If you're unsure about any of these, don't hesitate to ask. We're
here to help! -->
    
URL: sagemath#35467
Reported by: Kwankyu Lee
Reviewer(s): Kwankyu Lee, Matthias Köppe
vbraun pushed a commit to vbraun/sage that referenced this pull request Apr 25, 2024
    
<!-- Please provide a concise, informative and self-explanatory title.
-->
<!-- Don't put issue numbers in the title. Put it in the Description
below. -->
<!-- For example, instead of "Fixes sagemath#12345", use "Add a new method to
multiply two integers" -->

### 📚 Description

We attach Jacobians to function fields and curves, enabling arithmetic
with the points of the Jacobian. Fixes sagemath#34232.

A point of Jacobian is represented by an effective divisor `D` such that
the point is the divisor class of `D - B` (of degree 0) with a fixed
base divisor `B`.

There are two models for Jacobian arithmetic:

- Hess model:  `D` is internally represented by a pair of certain ideals
and arithmetic relies on divisor reduction using Riemann-Roch space
computation by Hess' algorithm.
- Khuri-Makdisi model: `D` is internally represented by a linear
subspace `W_D` of a linear space `V` and arithmetic uses Khuri-Makdisi's
linear algebra algorithms. For implementation, sagemath#15113 was referenced.


An example with non-hyperelliptic genus 3 curve:
```sage
sage: A2.<x,y> = AffineSpace(QQ, 2)
sage: f = y^3 + x^4 - 5*x^2*y + 2*x*y - x^2 - 5*y - 4*x + 1
sage: C = Curve(f, A2)
sage: X = C.projective_closure()
sage: X.genus()
3
sage: X.rational_points(bound=5)
[(0 : 0 : 1), (1/3 : 1/3 : 1)]
sage: Q = X(0,0,1).place()
sage: P = X(1,1,3).place()
sage: D = P - Q
sage: D.degree()
0
sage: J = X.jacobian(model='hess', base_div=3*Q)
sage: G = J.group()
sage: p = G.point(D)
sage: 2*p + 3*p == 5*p
True
```

An example with elliptic curve:
```sage
sage: k.<a> = GF((5,2))
sage: E = EllipticCurve(k,[1,0]); E
Elliptic Curve defined by y^2 = x^3 + x over Finite Field in a of size
5^2
sage: E.order()
32
sage: P = E([a, 2*a + 4])
sage: P
(a : 2*a + 4 : 1)
sage: P.order()
8
sage: p = P.point_of_jacobian_of_curve()
sage: p
[Place (x + 4*a, y + 3*a + 1)]
sage: p.order()
8
sage: Q = 3*P
sage: q = Q.point_of_jacobian_of_curve()
sage: q == 3*p
True
sage: G = p.parent()
sage: G.order()
32
sage: G
Group of rational points of Jacobian over Finite Field in a of size 5^2
(Hess model)
sage: J = G.parent(); J
Jacobian of Projective Plane Curve over Finite Field in a of size 5^2
 defined by x^2*y + y^3 - x*z^2 (Hess model)
sage: J.curve() == E.affine_patch(2).projective_closure()
True
```

An example with hyperelliptic curve:
```sage
sage: R.<x> = PolynomialRing(GF(11))
sage: f = x^6 + x + 1
sage: H = HyperellipticCurve(f)
sage: J = H.jacobian()
sage: D = J(H.lift_x(1))
sage: D  # divisor in Mumford representation
(x + 10, y + 6)
sage: jacobian_order = sum(H.frobenius_polynomial())
sage: jacobian_order
234
sage: p = D.point_of_jacobian_of_curve(); p
sage: p  # Jacobian point represented by an effective divisor
[Place (1/x0, 1/x0^3*x1 + 1)
 + Place (x0 + 10, x1 + 6)]
sage: p.order()
39
sage: 234*p == 0
True
sage: G = p.parent()
sage: G
Group of rational points of Jacobian over Finite Field of size 11 (Hess
model)
sage: J = G.parent()
sage: J
Jacobian of Projective Plane Curve over Finite Field of size 11
 defined by x0^6 + x0^5*x1 + x1^6 - x0^4*x2^2 (Hess model)
sage: C = J.curve()
sage: C
Projective Plane Curve over Finite Field of size 11
 defined by x0^6 + x0^5*x1 + x1^6 - x0^4*x2^2
sage: C.affine_patch(0) == H.affine_patch(2)
True
```

[![Binder](https://mybinder.org/badge_logo.svg)](https://mybinder.org/v2
/gh/kwankyu/sage/p/35467/add-jacobian-groups-notebook-binder) prepared
with sagemath#36245

<!-- Describe your changes here in detail. -->
<!-- Why is this change required? What problem does it solve? -->
<!-- If this PR resolves an open issue, please link to it here. For
example "Fixes sagemath#12345". -->
<!-- If your change requires a documentation PR, please link it
appropriately. -->

### 📝 Checklist

<!-- Put an `x` in all the boxes that apply. It should be `[x]` not `[x
]`. -->

- [x] The title is concise, informative, and self-explanatory.
- [x] The description explains in detail what this PR is about.
- [x] I have linked a relevant issue or discussion.
- [x] I have created tests covering the changes.
- [x] I have updated the documentation accordingly.

### ⌛ Dependencies

<!-- List all open PRs that this PR logically depends on
- sagemath#12345: short description why this is a dependency
- sagemath#34567: ...
-->

<!-- If you're unsure about any of these, don't hesitate to ask. We're
here to help! -->
    
URL: sagemath#35467
Reported by: Kwankyu Lee
Reviewer(s): Kwankyu Lee, Matthias Köppe
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