Constant curve25519_dalek::constants::EIGHT_TORSION
source · pub const EIGHT_TORSION: [EdwardsPoint; 8];
Available on
curve25519_dalek_bits="32"
only.Expand description
The 8-torsion subgroup \(\mathcal E [8]\).
In the case of Curve25519, it is cyclic; the \(i\)-th element of the array is \([i]P\), where \(P\) is a point of order \(8\) generating \(\mathcal E[8]\).
Thus \(\mathcal E[4]\) is the points indexed by 0,2,4,6
, and
\(\mathcal E[2]\) is the points indexed by 0,4
.
The Ed25519 basepoint has y = 4/5. This is called _POINT
to
distinguish it from _TABLE
, which should be used for scalar
multiplication (it’s much faster).