Converting Boost Multiprecision to a string with current locale settings












0















I'm working with the boost cpp_dec_float class, but can't get a string out of it with the correct regional settings (decimal symbol and grouping symbol).



Looking at the boost code, it looks like the internal str()-function always inserts a '.' character as decimal point. See format_float_string in number_base.



This is what I get with a regular double:



double d = 1494.33;

std::stringstream ss;

ss.imbue(std::locale(""));

ss << std::fixed << std::setprecision(6) << d;

std::cout << ss.str() << std::endl;


outputs 1.494,330000



Trying the same with dec_float:



boost::multiprecision::cpp_dec_float_50 df = 1494.33;

std::stringstream ss;

ss.imbue(std::locale(""));

ss << std::fixed << std::setprecision(6) << df;

std::cout << ss.str() << std::endl;


outputs 1494.330000



I'm looking for a solution that avoids converting the dec_float back to a double, as that would introduce some inaccuracy.






c++ boost boost-multiprecision







share|improve this question























  • I doubt it has been implemented. You could submit a github issue: github.com/boostorg/multiprecision

    – user14717
    Dec 5 '18 at 0:53
















0















I'm working with the boost cpp_dec_float class, but can't get a string out of it with the correct regional settings (decimal symbol and grouping symbol).



Looking at the boost code, it looks like the internal str()-function always inserts a '.' character as decimal point. See format_float_string in number_base.



This is what I get with a regular double:



double d = 1494.33;

std::stringstream ss;

ss.imbue(std::locale(""));

ss << std::fixed << std::setprecision(6) << d;

std::cout << ss.str() << std::endl;


outputs 1.494,330000



Trying the same with dec_float:



boost::multiprecision::cpp_dec_float_50 df = 1494.33;

std::stringstream ss;

ss.imbue(std::locale(""));

ss << std::fixed << std::setprecision(6) << df;

std::cout << ss.str() << std::endl;


outputs 1494.330000



I'm looking for a solution that avoids converting the dec_float back to a double, as that would introduce some inaccuracy.






c++ boost boost-multiprecision







share|improve this question























  • I doubt it has been implemented. You could submit a github issue: github.com/boostorg/multiprecision

    – user14717
    Dec 5 '18 at 0:53














0












0








0








I'm working with the boost cpp_dec_float class, but can't get a string out of it with the correct regional settings (decimal symbol and grouping symbol).



Looking at the boost code, it looks like the internal str()-function always inserts a '.' character as decimal point. See format_float_string in number_base.



This is what I get with a regular double:



double d = 1494.33;

std::stringstream ss;

ss.imbue(std::locale(""));

ss << std::fixed << std::setprecision(6) << d;

std::cout << ss.str() << std::endl;


outputs 1.494,330000



Trying the same with dec_float:



boost::multiprecision::cpp_dec_float_50 df = 1494.33;

std::stringstream ss;

ss.imbue(std::locale(""));

ss << std::fixed << std::setprecision(6) << df;

std::cout << ss.str() << std::endl;


outputs 1494.330000



I'm looking for a solution that avoids converting the dec_float back to a double, as that would introduce some inaccuracy.






c++ boost boost-multiprecision







share|improve this question














I'm working with the boost cpp_dec_float class, but can't get a string out of it with the correct regional settings (decimal symbol and grouping symbol).



Looking at the boost code, it looks like the internal str()-function always inserts a '.' character as decimal point. See format_float_string in number_base.



This is what I get with a regular double:



double d = 1494.33;

std::stringstream ss;

ss.imbue(std::locale(""));

ss << std::fixed << std::setprecision(6) << d;

std::cout << ss.str() << std::endl;


outputs 1.494,330000



Trying the same with dec_float:



boost::multiprecision::cpp_dec_float_50 df = 1494.33;

std::stringstream ss;

ss.imbue(std::locale(""));

ss << std::fixed << std::setprecision(6) << df;

std::cout << ss.str() << std::endl;


outputs 1494.330000



I'm looking for a solution that avoids converting the dec_float back to a double, as that would introduce some inaccuracy.






c++ boost boost-multiprecision




c++ boost boost-multiprecision






share|improve this question













share|improve this question











share|improve this question




share|improve this question










asked Nov 27 '18 at 9:54









ShalieShalie

111




111













  • I doubt it has been implemented. You could submit a github issue: github.com/boostorg/multiprecision

    – user14717
    Dec 5 '18 at 0:53



















  • I doubt it has been implemented. You could submit a github issue: github.com/boostorg/multiprecision

    – user14717
    Dec 5 '18 at 0:53

















I doubt it has been implemented. You could submit a github issue: github.com/boostorg/multiprecision

– user14717
Dec 5 '18 at 0:53





I doubt it has been implemented. You could submit a github issue: github.com/boostorg/multiprecision

– user14717
Dec 5 '18 at 0:53












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