Rules / Types, classes & roles / basic

Rat Reference

Rational number (limited-precision)

What it is #

Position in the hierarchy #

Inherits from—
Does—
Inherited byRatStr

Routines #

Signatures are reproduced from the documentation, including their declared return types. A routine listed here is part of the type's published interface; whether Raku++ implements it is a separate question, answered by the examples below.

method raku #

multi method raku(Rat:D: --> Str:D)

Returns Str:D.

Returns an implementation-specific string that produces an equivalent object when given to EVAL.

Examples, run three ways #

Every example below comes from the official documentation, together with the output that documentation asserts. Each was then executed by Rakudo and by Raku++ when this page was built. Where the three agree, one result is shown; where they do not, all three are — because which of them is wrong is exactly the information worth having.

1 no-output · 4 ok

class Rat is Cool does Rational[Int, uint64] { }

Not executed: the documentation states no expected output for this example.

say 3.1;          # OUTPUT: «3.1␤»      (same as: Rat.new(31, 10))
say 3.1.^name;    # OUTPUT: «Rat␤»
say 3.1.nude;     # OUTPUT: «(31 10)␤»
Output
3.1
Rat
(31 10)

Documentation, Rakudo and Raku++ all agree.

say <1/2>;        # OUTPUT: «0.5␤»      (same as: Rat.new(1, 2))
say <1/2>.^name;  # OUTPUT: «Rat␤»
say <1/2>.nude;   # OUTPUT: «(1 2)␤»
Output
0.5
Rat
(1 2)

Documentation, Rakudo and Raku++ all agree.

sub approx-sqrt($n, $iterations) {
    my $x = $n;
    $x = ($x + $n / $x) / 2 for ^$iterations;
    return $x;
}
say approx-sqrt(2, 5).^name;     # OUTPUT: «Rat␤»
say approx-sqrt(2, 10).^name;    # OUTPUT: «Num␤»
Output
Rat
Num

Documentation, Rakudo and Raku++ all agree.

say (1/3).raku;                # OUTPUT: «<1/3>␤»
say (2/4).raku;                # OUTPUT: «0.5␤»
Output
<1/3>
0.5

Documentation, Rakudo and Raku++ all agree.