Trait overview

Trait Description
$\text{cofactor}()$ The order of the prime order subgroup and its cofactor
$\text{discriminant}()$ Factorization of the discriminant of the Frobenius polynomial, i.e. factorization of $t^2-4p=v^2d_K$, where $t$ is the trace of Frobenius, $v$ is the maximal conductor and $d_K$ is the CM discriminant.
$\text{twist_order}(deg)$ Factorization of the quadratic twist cardinality in an extension, i.e. $\#E(\mathbb{F}_{p^d})$.
$\text{kn_factorization}(k)$ Factorization of $kn \pm 1$ where $n$ is the cardinality of the curve.
$\text{torsion_extension}(l)$ Degrees of field extensions containing the least nontrivial $l$-torsion, the full $l$-torsion and their relative degree of extension.
$\text{conductor}(deg)$ Factorization of ratio of the maximal conductors of CM-field over an extension and over a basefield.
$\text{embedding}()$ The complement of the embedding degree, i.e. $(n-1)/e$ where $n$ is the prime-subgroup order and $e$ is the embedding degree.
$\text{class_number}()$ Upper and lower bound for the class number of the CM-field.
$\text{small_prime_order}(l)$ Multiplicative orders of small primes modulo the prime-subgroup order.
$\text{division_polynomials}(l)$ Factorizations of small division polynomials.
$\text{volcano}(l)$ Volcano depth and crater degree of the $l$-isogeny graph.
$\text{isogeny_extension}(l)$ The least field extensions containing a nontrivial number and full number of $l$-isogenies and their relative ratio.
$\text{trace_factorization}(deg)$ Factorization of trace in field extensions.
$\text{isogeny_neighbors}(l)$ Number of $j$-invariants adjacent to the curve by $l$-isogeny. This is the degree of the point in the $l$-isogeny graph.
$\text{q_torsion}()$ Torsion order of the lift of $E$ to $Q$.
$\text{hamming_x}(weight)$ Number of points with low Hamming weight of the $x$-coordinate and the expected weight.
$\text{square_4p1}()$ Square parts of $4q \pm 1$ and $4n \pm 1$.
$\text{pow_distance}()$ Distance of $n$ from the nearest power of two and multiple of 32/64.
$\text{multiples_x}(k)$ Bitlength of the $x$-coordinate of small inverted generator scalar multiples, i.e. $x$-coordinate of $P$ where $kP=G$. The difference and ratio to the bitlength of the whole group is also considered.
$\text{x962_invariant}()$ Computation of $a^3/b^2$.
$\text{brainpool_overlap}()$ Bit overlaps in curve coefficients
$\text{weierstrass}()$ Coefficients of the curve in Weierstrass form