invert()

void M2::ARingCCC::invert ( ElementType & result, const ElementType & a ) const

inline

Definition at line 245 of file aring-CCC.hpp.

  {
    mpfr_t p, denom;
    mpfr_init2(p, get_precision());
    mpfr_init2(denom, get_precision());
 
    if (mpfr_cmpabs(&a.re, &a.im) >= 0)
      {
        // double p = &a.im/&a.re;
        // double denom = &a.re + p * &a.im;
        // &result.re = 1.0/denom;
        // &result.im = - p/denom;
 
        mpfr_div(p, &a.im, &a.re, MPFR_RNDN);
        mpfr_mul(denom, p, &a.im, MPFR_RNDN);
        mpfr_add(denom, denom, &a.re, MPFR_RNDN);
        mpfr_si_div(&result.re, 1, denom, MPFR_RNDN);
        mpfr_div(&result.im, p, denom, MPFR_RNDN);
        mpfr_neg(&result.im, &result.im, MPFR_RNDN);
      }
    else
      {
        // double p = &a.re/&a.im;
        // double denom = &a.im + p * &a.re;
        // &result.re = p/denom;
        // &result.im = -1.0/denom;
 
        mpfr_div(p, &a.re, &a.im, MPFR_RNDN);
        mpfr_mul(denom, p, &a.re, MPFR_RNDN);
        mpfr_add(denom, denom, &a.im, MPFR_RNDN);
        mpfr_si_div(&result.im, 1, denom, MPFR_RNDN);
        mpfr_neg(&result.im, &result.im, MPFR_RNDN);
        mpfr_div(&result.re, p, denom, MPFR_RNDN);
      }
 
    mpfr_clear(p);
    mpfr_clear(denom);
  }

References get_precision(), p, and result().

Referenced by power().