struct BigRational
Overview
Rational numbers are represented as the quotient of arbitrarily large numerators and denominators. Rationals are canonicalized such that the denominator and the numerator have no common factors, and that the denominator is positive. Zero has the unique representation 0/1.
NOTE To use BigRational
, you must explicitly import it with require "big"
require "big"
r = BigRational.new(7.to_big_i, 3.to_big_i)
r.to_s # => "7/3"
r = BigRational.new(3, -9)
r.to_s # => "-1/3"
It is implemented under the hood with GMP.
Included Modules
Defined in:
big.crbig/big_decimal.cr
big/big_rational.cr
big/number.cr
Constructors
-
.new(numerator : Int, denominator : Int)
Creates a new
BigRational
. -
.new(num : Int)
Creates a new
BigRational
with num as the numerator and 1 for denominator. -
.new(num : Float::Primitive)
Creates an exact representation of float as rational.
-
.new(num : BigFloat)
Creates an exact representation of float as rational.
-
.new(num : BigRational)
Creates a
BigRational
from the given num. -
.new(num : BigDecimal)
Creates a
BigRational
from the given num.
Instance Method Summary
- #*(other : BigRational) : BigRational
- #*(other : Int) : BigRational
-
#**(other : Int) : BigRational
Raises the rational to the otherth power
- #+(other : BigRational) : BigRational
- #+(other : Int) : BigRational
- #-(other : BigRational) : BigRational
- #-(other : Int) : BigRational
- #- : BigRational
- #/(other : BigRational) : BigRational
- #/(other : BigInt) : BigRational
- #/(other : BigFloat) : BigRational
- #/(other : BigDecimal) : BigRational
- #/(other : Int8) : BigRational
- #/(other : UInt8) : BigRational
- #/(other : Int16) : BigRational
- #/(other : UInt16) : BigRational
- #/(other : Int32) : BigRational
- #/(other : UInt32) : BigRational
- #/(other : Int64) : BigRational
- #/(other : UInt64) : BigRational
- #/(other : Int128) : BigRational
- #/(other : UInt128) : BigRational
- #/(other : Float32) : BigRational
- #/(other : Float64) : BigRational
-
#<<(other : Int) : BigRational
Multiplies the rational by (2 ** other)
- #<=>(other : BigRational)
- #<=>(other : Float::Primitive)
- #<=>(other : BigFloat)
- #<=>(other : BigInt)
- #<=>(other : Int)
-
#<=>(other : BigDecimal)
The comparison operator.
- #==(other : BigRational) : Bool
-
#>>(other : Int) : BigRational
Divides the rational by (2 ** other)
-
#abs : BigRational
Returns the absolute value of this number.
- #ceil : BigRational
- #clone
- #denominator : BigInt
- #floor : BigRational
-
#hash(hasher)
TODO improve this
-
#inspect(io : IO) : Nil
Prints to io an unambiguous and information-rich string representation of this object, typically intended for developers.
-
#inspect : String
Returns an unambiguous and information-rich string representation of this object, typically intended for developers.
-
#integer? : Bool
Returns
true
ifself
is an integer. -
#inv : BigRational
Returns a new
BigRational
as 1/r. - #numerator : BigInt
- #round_away : BigRational
- #round_even : BigRational
-
#to_big_d : BigDecimal
Converts
self
toBigDecimal
. - #to_big_f : BigFloat
- #to_big_i : BigInt
-
#to_big_r : BigRational
Returns
self
. -
#to_f : Float64
Returns the
Float64
representing this rational. - #to_f! : Float64
- #to_f32 : Float32
- #to_f32! : Float32
- #to_f64 : Float64
- #to_f64! : Float64
- #to_i16(*args, **options)
- #to_i16(*args, **options, &)
- #to_i32(*args, **options)
- #to_i32(*args, **options, &)
- #to_i64(*args, **options)
- #to_i64(*args, **options, &)
- #to_i8(*args, **options)
- #to_i8(*args, **options, &)
-
#to_s(base : Int = 10) : String
Returns the string representing this rational.
-
#to_s(io : IO, base : Int = 10) : Nil
Prints a nicely readable and concise string representation of this object, typically intended for users, to io.
- #to_u16(*args, **options)
- #to_u16(*args, **options, &)
- #to_u32(*args, **options)
- #to_u32(*args, **options, &)
- #to_u64(*args, **options)
- #to_u64(*args, **options, &)
- #to_u8(*args, **options)
- #to_u8(*args, **options, &)
- #to_unsafe
- #trunc : BigRational
Instance methods inherited from module Comparable(BigDecimal)
<(other : T) : Bool
<,
<=(other : T)
<=,
<=>(other : T)
<=>,
==(other : T)
==,
>(other : T) : Bool
>,
>=(other : T)
>=,
clamp(min, max)clamp(range : Range) clamp
Instance methods inherited from module Comparable(Float)
<(other : T) : Bool
<,
<=(other : T)
<=,
<=>(other : T)
<=>,
==(other : T)
==,
>(other : T) : Bool
>,
>=(other : T)
>=,
clamp(min, max)clamp(range : Range) clamp
Instance methods inherited from module Comparable(Int)
<(other : T) : Bool
<,
<=(other : T)
<=,
<=>(other : T)
<=>,
==(other : T)
==,
>(other : T) : Bool
>,
>=(other : T)
>=,
clamp(min, max)clamp(range : Range) clamp
Instance methods inherited from module Comparable(BigRational)
<(other : T) : Bool
<,
<=(other : T)
<=,
<=>(other : T)
<=>,
==(other : T)
==,
>(other : T) : Bool
>,
>=(other : T)
>=,
clamp(min, max)clamp(range : Range) clamp
Instance methods inherited from struct Number
*(other : BigFloat) : BigFloat*(other : Complex) : Complex *, +(other : BigFloat)
+(other : Complex) : Complex
+ +, -(other : BigFloat)
-(other : Complex) : Complex -, /(other : BigFloat) : BigFloat
/(other : Complex) : Complex /, //(other) //, <=>(other) : Int32 | Nil <=>, ==(other : Complex) ==, abs : self abs, abs2 abs2, cis : Complex cis, divmod(number) divmod, format(io : IO, separator = '.', delimiter = ',', decimal_places : Int | Nil = nil, *, group : Int = 3, only_significant : Bool = false) : Nil
format(separator = '.', delimiter = ',', decimal_places : Int | Nil = nil, *, group : Int = 3, only_significant : Bool = false) : String format, humanize(io : IO, precision = 3, separator = '.', delimiter = ',', *, base = 10 ** 3, significant = true, prefixes : Indexable = SI_PREFIXES) : Nil
humanize(io : IO, precision = 3, separator = '.', delimiter = ',', *, base = 10 ** 3, significant = true, prefixes : Proc) : Nil
humanize(precision = 3, separator = '.', delimiter = ',', *, base = 10 ** 3, significant = true, prefixes = SI_PREFIXES) : String
humanize(io : IO, precision = 3, separator = '.', delimiter = ',', *, base = 10 ** 3, significant = true, &prefixes : Int32, Float64 -> Tuple(Int32, _) | Tuple(Int32, _, Bool)) : Nil
humanize(precision = 3, separator = '.', delimiter = ',', *, base = 10 ** 3, significant = true, &) : String
humanize(precision = 3, separator = '.', delimiter = ',', *, base = 10 ** 3, significant = true, prefixes : Proc) : String humanize, i : Complex i, integer? : Bool integer?, negative? : Bool negative?, positive? : Bool positive?, round(mode : RoundingMode = :ties_even) : self
round(digits : Number, base = 10, *, mode : RoundingMode = :ties_even) round, sign : Int32 sign, significant(digits, base = 10) significant, step(*, to limit = nil, exclusive : Bool = false, &) : Nil
step(*, to limit = nil, exclusive : Bool = false) step, to_big_f : BigFloat to_big_f, to_c : Complex to_c, to_yaml(yaml : YAML::Nodes::Builder) : Nil to_yaml, zero? : Bool zero?
Constructor methods inherited from struct Number
additive_identity : self
additive_identity,
multiplicative_identity : self
multiplicative_identity,
zero : self
zero
Class methods inherited from struct Number
si_prefix(magnitude : Int, prefixes = SI_PREFIXES) : Char | Nil
si_prefix
Instance methods inherited from module Comparable(BigFloat)
<(other : T) : Bool
<,
<=(other : T)
<=,
<=>(other : T)
<=>,
==(other : T)
==,
>(other : T) : Bool
>,
>=(other : T)
>=,
clamp(min, max)clamp(range : Range) clamp
Instance methods inherited from module Steppable
step(*, to limit = nil, by step, exclusive : Bool = false, &) : Nilstep(*, to limit = nil, by step, exclusive : Bool = false) step
Instance methods inherited from module Comparable(Number)
<(other : T) : Bool
<,
<=(other : T)
<=,
<=>(other : T)
<=>,
==(other : T)
==,
>(other : T) : Bool
>,
>=(other : T)
>=,
clamp(min, max)clamp(range : Range) clamp
Instance methods inherited from struct Value
==(other : JSON::Any)==(other : YAML::Any)
==(other) ==, dup dup
Instance methods inherited from class Object
! : Bool
!,
!=(other)
!=,
!~(other)
!~,
==(other)
==,
===(other : JSON::Any)===(other : YAML::Any)
===(other) ===, =~(other) =~, as(type : Class) as, as?(type : Class) as?, class class, dup dup, hash(hasher)
hash hash, in?(collection : Object) : Bool
in?(*values : Object) : Bool in?, inspect(io : IO) : Nil
inspect : String inspect, is_a?(type : Class) : Bool is_a?, itself itself, nil? : Bool nil?, not_nil!(message)
not_nil! not_nil!, pretty_inspect(width = 79, newline = "\n", indent = 0) : String pretty_inspect, pretty_print(pp : PrettyPrint) : Nil pretty_print, responds_to?(name : Symbol) : Bool responds_to?, tap(&) tap, to_json(io : IO) : Nil
to_json : String to_json, to_pretty_json(indent : String = " ") : String
to_pretty_json(io : IO, indent : String = " ") : Nil to_pretty_json, to_s(io : IO) : Nil
to_s : String to_s, to_yaml(io : IO) : Nil
to_yaml : String to_yaml, try(&) try, unsafe_as(type : T.class) forall T unsafe_as
Class methods inherited from class Object
from_json(string_or_io, root : String)from_json(string_or_io) from_json, from_yaml(string_or_io : String | IO) from_yaml
Constructor Detail
Creates a new BigRational
.
If denominator is 0, this will raise an exception.
Creates a new BigRational
with num as the numerator and 1 for denominator.
Creates an exact representation of float as rational.
Raises ArgumentError
if num is not finite.
Instance Method Detail
Raises the rational to the otherth power
This will raise DivisionByZeroError
if rational is 0 and other is negative.
require "big"
BigRational.new(2, 3) ** 2 # => 4/9
BigRational.new(2, 3) ** -1 # => 3/2
Multiplies the rational by (2 ** other)
require "big"
BigRational.new(2, 3) << 2 # => 8/3
The comparison operator. Returns 0
if the two objects are equal,
a negative number if this object is considered less than other,
a positive number if this object is considered greater than other,
or nil
if the two objects are not comparable.
Subclasses define this method to provide class-specific ordering.
The comparison operator is usually used to sort values:
# Sort in a descending way:
[3, 1, 2].sort { |x, y| y <=> x } # => [3, 2, 1]
# Sort in an ascending way:
[3, 1, 2].sort { |x, y| x <=> y } # => [1, 2, 3]
Divides the rational by (2 ** other)
require "big"
BigRational.new(2, 3) >> 2 # => 1/6
Returns the absolute value of this number.
123.abs # => 123
-123.abs # => 123
Prints to io an unambiguous and information-rich string representation of this object, typically intended for developers.
It is similar to #to_s(IO)
, but often provides more information. Ideally, it should
contain sufficient information to be able to recreate an object with the same value
(given an identical environment).
For types that don't provide a custom implementation of this method,
default implementation delegates to #to_s(IO)
. This said, it is advisable to
have an appropriate #inspect
implementation on every type. Default
implementations are provided by Struct#inspect
and Reference#inspect
.
::p
and ::p!
use this method to print an object in STDOUT
.
Returns an unambiguous and information-rich string representation of this object, typically intended for developers.
This method should usually not be overridden. It delegates to
#inspect(IO)
which can be overridden for custom implementations.
Also see #to_s
.
Returns true
if self
is an integer.
Non-integer types may return true
as long as self
denotes a finite value
without any fractional parts.
1.integer? # => true
1.0.integer? # => true
1.2.integer? # => false
(1 / 0).integer? # => false
(0 / 0).integer? # => false
Returns a new BigRational
as 1/r.
This will raise an exception if rational is 0.
Returns the string representing this rational.
Optionally takes a radix base (2 through 36).
require "big"
r = BigRational.new(8243243, 562828882)
r.to_s # => "8243243/562828882"
r.to_s(16) # => "7dc82b/218c1652"
r.to_s(36) # => "4woiz/9b3djm"
Prints a nicely readable and concise string representation of this object, typically intended for users, to io.
This method is called when an object is interpolated in a string literal:
"foo #{bar} baz" # calls bar.to_io with the builder for this string
IO#<<
calls this method to append an object to itself:
io << bar # calls bar.to_s(io)
Thus implementations must not interpolate self
in a string literal or call
io << self
which both would lead to an endless loop.
Also see #inspect(IO)
.