@@ -312,11 +312,16 @@ def differential_basis_baker(f):
312312 that is nonsingular outside the coordinate points at infinity
313313 (1:0:0), (0:1:0), and (0:0:1).
314314
315- This method applies Baker's theorem, which states that if a curve's
316- singularities are restricted to the coordinate vertices in the projective
317- plane and it meets certain easily testable genericity criteria, a basis
318- for the regular differentials can be derived from the interior integral
319- points of its Newton polygon.
315+ Baker's theorem tells us that if a curve has its singularities at
316+ the coordinate vertices and meets some further easily tested
317+ genericity criteria, then we can read off a basis for the regular
318+ differentials from the interior of the Newton polygon spanned by
319+ the monomials. While this theorem only applies to special plane curves
320+ it is worth implementing because the analysis is relatively cheap
321+ and it applies to a lot of commonly encountered curves (e.g.,
322+ curves given by a hyperelliptic model). Other advantages include
323+ that we can do the computation over any exact base ring
324+ (the alternative Singular based method requires rationals).
320325
321326 This approach is advantageous for curves meeting these criteria (e.g.,
322327 many hyperelliptic curves) because it is computationally inexpensive,
@@ -805,7 +810,7 @@ def w_values(self, z0):
805810 sage: f = w^2 - z^4 + 1
806811 sage: S = RiemannSurface(f)
807812
808- Find the w-values above the origin ( i.e. solutions to `w^2 + 1 = 0`) ::
813+ Find the w-values above the origin, i.e. solutions to `w^2 + 1 = 0`::
809814
810815 sage: S.w_values(0) # abs tol 1e-14
811816 [-1.00000000000000*I, 1.00000000000000*I]
@@ -2886,10 +2891,11 @@ def symplectic_automorphism_group(self, endo_basis=None, b=None, r=None):
28862891 Jacobian of the Riemann surface.
28872892
28882893 .. NOTE::
2889- The automorphism group of the Riemann surface itself can be
2890- recovered from this: if the curve is hyperelliptic, this group is
2891- isomorphic to the curve's automorphism group. Otherwise, one typically
2892- quotients by the central element corresponding to multiplication by -1.
2894+ The symplectic automorphism group of the Jacobian of the Riemann
2895+ surface. The automorphism group of the Riemann surface itself can be
2896+ recovered from this; if the curve is hyperelliptic, then it is
2897+ identical, and if not, then one divides out by the central element
2898+ corresponding to multiplication by -1.
28932899
28942900 EXAMPLES::
28952901
@@ -3963,9 +3969,9 @@ def integer_matrix_relations(M1, M2, b=None, r=None):
39633969
39643970 OUTPUT:
39653971
3966- A list of `2*g1 \times 2*g2 ` integer matrices (where `g1 ` and `g2 ` are
3967- the dimensions of `M1` and `M2` respectively). For sufficiently
3968- chosen `r` and `b-r` , these matrices form a `\ZZ`-basis for the
3972+ A list of `2*g \times 2*h ` integer matrices (where `g ` and `h ` are
3973+ the dimensions of `M1` and `M2` respectively). When `r` and `b-r` are
3974+ chosen to be sufficiently large , these matrices form a `\ZZ`-basis for the
39693975 module of transformations `(D, B; C, A)` satisfying the condition.
39703976
39713977 EXAMPLES::
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