bridge/class-master/depend/pari/src/basemath/F2xqE.c
/* Computes the equation of the line tangent to R and returns its
   evaluation at the point Q. Also doubles the point R.
 */
Computes the equation of the line tangent to R and returns its
evaluation at the point Q. Also doubles the point R.
Computes the equation of the line tangent to R and returns its evaluation at the point Q . Also doubles the point R .
static GEN
F2xqE_tangent_update(GEN R, GEN Q, GEN a2, GEN T, GEN *pt_R)
{
  if (ell_is_inf(R))
  {
    *pt_R = ellinf();
    return pol1_F2x(T[1]);
  }
  else if (is_2_torsion(R, a2))
  {
    *pt_R = ellinf();
    return F2xqE_vert(R, Q, a2, T);
  } else {
    GEN slope;
    *pt_R = F2xqE_dbl_slope(R, a2, T, &slope);
    return F2xqE_Miller_line(R, Q, slope, a2, T);
  }
}
static GEN F2xqE_tangent_update ( GEN R , GEN Q , GEN a2 , GEN T , GEN * pt_R ) { if ( ell_is_inf ( R ) ) { * pt_R = ellinf ( ) ; return pol1_F2x ( T [ 1 ] ) ; } else if ( is_2_torsion ( R , a2 ) ) { * pt_R = ellinf ( ) ; return F2xqE_vert ( R , Q , a2 , T ) ; } else { GEN slope ; * pt_R = F2xqE_dbl_slope ( R , a2 , T , & slope ) ; return F2xqE_Miller_line ( R , Q , slope , a2 , T ) ; } }
Computes the equation of the line tangent to R and returns its
evaluation at the point Q.
Computes the equation of the line tangent to R and returns its evaluation at the point Q .