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NAME

Math::Ryu - perl interface to Ryu (float-to-string conversion).

DEPENDENCIES

   This module uses the Ryu C implementation,  which is included with
   this module's source. It is therefore unnecessary to download that
   Ryu code - but, should you wish to grab it, it's available at:
   https://github.com/ulfjack/ryu/tree/master/ryu

DESCRIPTION

   Convert an NV to a decimal string, such that no information is
   lost, yet keeping the string as short as possible.

   NOTE:
   NVs whose size is greater than 8 bytes are not currently catered for.

SYNOPSIS

   use Math::Ryu qw(:all);

   my $str = d2s(0.1);
   print $str;           # 1E-1

   $str = d2s(1.4 / 10);
   print $str;           # 1.3999999999999999E-1

   $str = d2s(sqrt 2);
   print $str;           # 1.4142135623730951E0

   # Also do the reverse of s2d()
   my $d = s2d('1E-1');
   printf "%.17g\n", $d; # 0.10000000000000001

FUNCTIONS

   $nv = s2d($str);
    Converts the string ($str) to a vloating point value ($nv)
    and return $nv.

   $str = d2s($nv);
    $nv holds a floating point numeric value.
    $str is a string in floating point format, that accurately
    and succinctly represents the value held by $nv.
    $str, when correctly assigned back to a perl number, will
    always be equivalent to $nv.
    This in stark contrast to perl's interpolation which does not
    guarantee that the condition ("$nv" == $nv) is true, even for
    non-nan values of $nv. (Eg if $nv is sqrt 2.0 or 1.4/10 .)
    Also, $str will contain as few digits as possible, without
    compromising that accuracy.

   $str = d2fixed($nv, $digits);
    $str is a $digits-decimal fixed point representation of $nv.
    For example, d2sfixed(1 / 10000, 6) returns '0.000100'.

   $str = d2exp($nv, $digits);
    $str is a $digits-decimal floating point representation of $nv.
    For example, d2exp(1 / 10000, 6) returns '1.000000e-04'.

   $str = d2s_buffered($nv);                       # Not very useful
    Returns the same as d2s($nv).

   ($str, $len) = d2s_buffered_n($nv);             # Not very useful
    $str is the same as returned by d2s($nv).
    $len is length($str).

   $str = d2fixed_buffered($nv, $digits);           # Not very useful
    Returns the same as d2fixed($nv, $digits).

   ($str, $len) = d2fixed_buffered_n($nv, $digits); # Not very useful
    $str is the same as returned by d2fixed($nv, $digits).
    $len is length($str).

   $str = d2exp_buffered($nv, $digits);             # Not very useful
    Returns the same as d2exp($nv, $digits).

   ($str, $len) = d2exp_buffered_n($nv, $digits);   # Not very useful
    $str is the same as returned by d2exp($nv, $digits).
    $len is length($str).

TODO

    Cover larger precision NV types (ie long double and __float128)

LICENSE

    This perl module is free software; you may redistribute it
    and/or modify it under the same terms as Perl itself.
    However, the ".c" and ".h" files that ship with this distro
    are Copyright 2018 Ulf Adams, and can only be used under the
    the terms of version 2.0 the Apache License, or of version 1.0
    of the Boost Software License.
    A copy of the Apache License (Apache_License.txt) is included
    with this distro.

    The Apache License can also be found at:
    http://www.apache.org/licenses/LICENSE-2.0

    The Boost Software License can be found at:
    https://www.boost.org/LICENSE_1_0.txt

    This perl module is Copyright 2021 Sisyphus

AUTHOR

    Sisyphus <sisyphus at(@) cpan dot (.) org>