diff options
Diffstat (limited to 'rational.c')
-rw-r--r-- | rational.c | 32 |
1 files changed, 20 insertions, 12 deletions
diff --git a/rational.c b/rational.c index 9601ee76df..d65dd74810 100644 --- a/rational.c +++ b/rational.c @@ -1510,12 +1510,16 @@ nurat_truncate_n(int argc, VALUE *argv, VALUE self) /* * call-seq: - * rat.round([ndigits] [, half: symbol]) -> integer or rational + * rat.round([ndigits] [, half: mode]) -> integer or rational * - * Rounds +rat+ to a given precision in decimal digits (default 0 digits). + * Returns +rat+ rounded to the nearest value with + * a precision of +ndigits+ decimal digits (default: 0). * - * Precision may be negative. Returns a rational when +ndigits+ - * is more than zero. + * When the precision is negative, the returned value is an integer + * with at least <code>ndigits.abs</code> trailing zeros. + * + * Returns a rational when +ndigits+ is positive, + * otherwise returns an integer. * * Rational(3).round #=> 3 * Rational(2, 3).round #=> 1 @@ -1528,14 +1532,18 @@ nurat_truncate_n(int argc, VALUE *argv, VALUE self) * Rational('-123.456').round(+1).to_f #=> -123.5 * Rational('-123.456').round(-1) #=> -120 * - * The <code>half:</code> optional keyword same as Float#round is available. - * - * Rational(25, 100).round(1, half: :up) #=> (3/10) - * Rational(25, 100).round(1, half: :even) #=> (1/5) - * Rational(25, 100).round(1, half: :down) #=> (1/5) - * Rational(35, 100).round(1, half: :up) #=> (2/5) - * Rational(35, 100).round(1, half: :even) #=> (2/5) - * Rational(35, 100).round(1, half: :down) #=> (3/10) + * The optional +half+ keyword argument is available + * similar to Float#round. + * + * Rational(25, 100).round(1, half: :up) #=> (3/10) + * Rational(25, 100).round(1, half: :down) #=> (1/5) + * Rational(25, 100).round(1, half: :even) #=> (1/5) + * Rational(35, 100).round(1, half: :up) #=> (2/5) + * Rational(35, 100).round(1, half: :down) #=> (3/10) + * Rational(35, 100).round(1, half: :even) #=> (2/5) + * Rational(-25, 100).round(1, half: :up) #=> (-3/10) + * Rational(-25, 100).round(1, half: :down) #=> (-1/5) + * Rational(-25, 100).round(1, half: :even) #=> (-1/5) */ static VALUE nurat_round_n(int argc, VALUE *argv, VALUE self) |