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Slight documentation updates after review.
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src/sage/schemes/riemann_surfaces/riemann_surface.py

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@@ -312,11 +312,16 @@ def differential_basis_baker(f):
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that is nonsingular outside the coordinate points at infinity
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(1:0:0), (0:1:0), and (0:0:1).
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This method applies Baker's theorem, which states that if a curve's
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singularities are restricted to the coordinate vertices in the projective
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plane and it meets certain easily testable genericity criteria, a basis
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for the regular differentials can be derived from the interior integral
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points of its Newton polygon.
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Baker's theorem tells us that if a curve has its singularities at
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the coordinate vertices and meets some further easily tested
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genericity criteria, then we can read off a basis for the regular
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differentials from the interior of the Newton polygon spanned by
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the monomials. While this theorem only applies to special plane curves
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it is worth implementing because the analysis is relatively cheap
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and it applies to a lot of commonly encountered curves (e.g.,
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curves given by a hyperelliptic model). Other advantages include
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that we can do the computation over any exact base ring
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(the alternative Singular based method requires rationals).
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This approach is advantageous for curves meeting these criteria (e.g.,
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many hyperelliptic curves) because it is computationally inexpensive,
@@ -805,7 +810,7 @@ def w_values(self, z0):
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sage: f = w^2 - z^4 + 1
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sage: S = RiemannSurface(f)
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Find the w-values above the origin (i.e. solutions to `w^2 + 1 = 0`)::
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Find the w-values above the origin, i.e. solutions to `w^2 + 1 = 0`::
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sage: S.w_values(0) # abs tol 1e-14
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[-1.00000000000000*I, 1.00000000000000*I]
@@ -2886,10 +2891,11 @@ def symplectic_automorphism_group(self, endo_basis=None, b=None, r=None):
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Jacobian of the Riemann surface.
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.. NOTE::
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The automorphism group of the Riemann surface itself can be
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recovered from this: if the curve is hyperelliptic, this group is
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isomorphic to the curve's automorphism group. Otherwise, one typically
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quotients by the central element corresponding to multiplication by -1.
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The symplectic automorphism group of the Jacobian of the Riemann
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surface. The automorphism group of the Riemann surface itself can be
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recovered from this; if the curve is hyperelliptic, then it is
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identical, and if not, then one divides out by the central element
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corresponding to multiplication by -1.
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EXAMPLES::
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@@ -3963,9 +3969,9 @@ def integer_matrix_relations(M1, M2, b=None, r=None):
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OUTPUT:
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A list of `2*g1 \times 2*g2` integer matrices (where `g1` and `g2` are
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the dimensions of `M1` and `M2` respectively). For sufficiently
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chosen `r` and `b-r`, these matrices form a `\ZZ`-basis for the
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A list of `2*g \times 2*h` integer matrices (where `g` and `h` are
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the dimensions of `M1` and `M2` respectively). When `r` and `b-r` are
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chosen to be sufficiently large, these matrices form a `\ZZ`-basis for the
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module of transformations `(D, B; C, A)` satisfying the condition.
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EXAMPLES::

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