toString() [2/2]

std::string mpfr::mpreal::toString ( int n = -1, int b = 10, mp_rnd_t mode = mpreal::get_default_rnd() ) const

inline

Definition at line 1799 of file mpreal.h.

{
    // TODO: Add extended format specification (f, e, rounding mode) as it done in output operator
    (void)b;
    (void)mode;
 
#if (MPFR_VERSION >= MPFR_VERSION_NUM(2,4,0))
 
    std::ostringstream format;
 
    int digits = (n >= 0) ? n : 2 + bits2digits(mpfr_get_prec(mpfr_srcptr()));
 
    format << "%." << digits << "RNg";
 
    return toString(format.str());
 
#else
 
    char *s, *ns = NULL;
    size_t slen, nslen;
    mp_exp_t exp;
    std::string out;
 
    if(mpfr_inf_p(mp))
    {
        if(mpfr_sgn(mp)>0) return "+Inf";
        else               return "-Inf";
    }
 
    if(mpfr_zero_p(mp)) return "0";
    if(mpfr_nan_p(mp))  return "NaN";
 
    s  = mpfr_get_str(NULL, &exp, b, 0, mp, mode);
    ns = mpfr_get_str(NULL, &exp, b, (std::max)(0,n), mp, mode);
 
    if(s!=NULL && ns!=NULL)
    {
        slen  = strlen(s);
        nslen = strlen(ns);
        if(nslen<=slen)
        {
            mpfr_free_str(s);
            s = ns;
            slen = nslen;
        }
        else {
            mpfr_free_str(ns);
        }
 
        // Make human eye-friendly formatting if possible
        if (exp>0 && static_cast<size_t>(exp)<slen)
        {
            if(s[0]=='-')
            {
                // Remove zeros starting from right end
                char* ptr = s+slen-1;
                while (*ptr=='0' && ptr>s+exp) ptr--;
 
                if(ptr==s+exp) out = std::string(s,exp+1);
                else           out = std::string(s,exp+1)+'.'+std::string(s+exp+1,ptr-(s+exp+1)+1);
 
                //out = string(s,exp+1)+'.'+string(s+exp+1);
            }
            else
            {
                // Remove zeros starting from right end
                char* ptr = s+slen-1;
                while (*ptr=='0' && ptr>s+exp-1) ptr--;
 
                if(ptr==s+exp-1) out = std::string(s,exp);
                else             out = std::string(s,exp)+'.'+std::string(s+exp,ptr-(s+exp)+1);
 
                //out = string(s,exp)+'.'+string(s+exp);
            }
 
        }else{ // exp<0 || exp>slen
            if(s[0]=='-')
            {
                // Remove zeros starting from right end
                char* ptr = s+slen-1;
                while (*ptr=='0' && ptr>s+1) ptr--;
 
                if(ptr==s+1) out = std::string(s,2);
                else         out = std::string(s,2)+'.'+std::string(s+2,ptr-(s+2)+1);
 
                //out = string(s,2)+'.'+string(s+2);
            }
            else
            {
                // Remove zeros starting from right end
                char* ptr = s+slen-1;
                while (*ptr=='0' && ptr>s) ptr--;
 
                if(ptr==s) out = std::string(s,1);
                else       out = std::string(s,1)+'.'+std::string(s+1,ptr-(s+1)+1);
 
                //out = string(s,1)+'.'+string(s+1);
            }
 
            // Make final string
            if(--exp)
            {
                if(exp>0) out += "e+"+mpfr::toString<mp_exp_t>(exp,std::dec);
                else       out += "e"+mpfr::toString<mp_exp_t>(exp,std::dec);
            }
        }
 
        mpfr_free_str(s);
        return out;
    }else{
        return "conversion error!";
    }
#endif
}

References mpfr::bits2digits(), exp, mp, mpfr_srcptr(), s, toString(), and toString().

Referenced by toString(), and toString().