Function recoverY [src]

Recover the Y coordinate from the X coordinate.

Prototype

pub fn recoverY(x: Fe, is_odd: bool) NotSquareError!Fe

Parameters

x: Feis_odd: bool

Possible Errors

Source

  pub fn recoverY(x: Fe, is_odd: bool) NotSquareError!Fe {
    const x3AxB = x.sq().mul(x).sub(x).sub(x).sub(x).add(B);
    var y = try x3AxB.sqrt();
    const yn = y.neg();
    y.cMov(yn, @intFromBool(is_odd) ^ @intFromBool(y.isOdd()));
    return y;
}  