Function eval_initial_form 

pub fn eval_initial_form<F: HardwareField + Into<Block128> + From<u128>>(
    pool: &PoolLayout,
    eta: F,
    rho: &[F],
    r_mix: &[Block128],
    shifted_claims: bool,
    claim_pads: &[u32],
    first_wire: u32,
) -> Result<InitialForm<F>>