 defined for backwards compatibility only and should not be used.</p>

<p>As well as the affine coordinates, a point can alternatively be described in terms of its Jacobian projective coordinates (for Fp curves only). Jacobian projective coordinates are expressed as three values x, y and z. Working in this coordinate system provides more efficient point multiplication operations. A mapping exists between Jacobian projective coordinates and affine coordinates. A Jacobian projective coordinate (x, y, z) can b