Rational

A module for rational numbers in Carp.

Fractions are expressed as pairs of integers: a numerator and a denominator. Mathematical operations and conversion primitives to and from integers and floating point numbers are provided.

(load "git@github.com:carpentry-org/rational@0.4")

(Rational.new 22 12) ; => (Rational 11/6)
(* (Rational.new 22 12) (Rational.new 1 6)) ; => (Rational 2/1)
(to-int (Rational.new 2 1)) ; => 2
(to-float (Rational.new 1 4)) ; => 0.25
(to-double (Rational.new 1 4)) ; => 0.25

=

defn

(Fn [(Ref Rational a), (Ref Rational a)] Bool) 

                    (= a b)

compares two Rationals a and b.

add

defn

(Fn [(Ref Rational a), (Ref Rational b)] Rational) 

                    (add a b)

adds two Rationals a and b.

copy

instantiate

(Fn [(Ref Rational a)] Rational)

copies a Rational.

denominator

instantiate

(Fn [(Ref Rational a)] (Ref Int a))

gets the denominator property of a Rational.

div

defn

(Fn [(Ref Rational a), (Ref Rational b)] Rational) 

                    (div a b)

divides two Rationals a and b.

from-double

defn

(Fn [Double] Rational) 

                    (from-double f)

builds a Rational from a Double d.

from-float

defn

(Fn [Float] Rational) 

                    (from-float f)

builds a Rational from a Float f.

from-int

defn

(Fn [Int] Rational) 

                    (from-int i)

builds a Rational from an Integer i.

hash

defn

(Fn [(Ref Rational a)] Int) 

                    (hash r)

calculates the hash of the Rational r.

modulo

defn

(Fn [(Ref Rational a), (Ref Rational b)] Rational) 

                    (modulo a b)

calculates the modulo of two Rationals a and b.

mul

defn

(Fn [(Ref Rational a), (Ref Rational b)] Rational) 

                    (mul a b)

multiplies two Rationals a and b.

new

defn

(Fn [Int, Int] Rational) 

                    (new n d)

builds a Rational from a numerator n and a denominator d.

numerator

instantiate

(Fn [(Ref Rational a)] (Ref Int a))

gets the numerator property of a Rational.

prn

instantiate

(Fn [(Ref Rational a)] String)

converts a Rational to a string.

set-denominator

instantiate

(Fn [Rational, Int] Rational)

sets the denominator property of a Rational.

set-denominator!

instantiate

(Fn [(Ref Rational a), Int] ())

sets the denominator property of a Rational in place.

set-numerator

instantiate

(Fn [Rational, Int] Rational)

sets the numerator property of a Rational.

set-numerator!

instantiate

(Fn [(Ref Rational a), Int] ())

sets the numerator property of a Rational in place.

str

defn

(Fn [(Ref Rational a)] String) 

                    (str r)

stringifies the Rational r. The format is (Rational <numerator>/<denominator>).

sub

defn

(Fn [(Ref Rational a), (Ref Rational b)] Rational) 

                    (sub a b)

subtracts two Rationals a and b.

to-double

defn

(Fn [(Ref Rational a)] Double) 

                    (to-double r)

converts a Rational r to a Double.

This function might incur a precision loss.

to-float

defn

(Fn [(Ref Rational a)] Float) 

                    (to-float r)

converts a Rational r to a Float.

This function might incur a precision loss.

to-int

defn

(Fn [(Ref Rational a)] Int) 

                    (to-int r)

converts a Rational r to an Integer.

This function might incur a precision loss.

update-denominator

instantiate

(Fn [Rational, (Ref (Fn [Int] Int a) b)] Rational)

updates the denominator property of a Rational using a function f.

update-numerator

instantiate

(Fn [Rational, (Ref (Fn [Int] Int a) b)] Rational)

updates the numerator property of a Rational using a function f.

zero

defn

(Fn [] Rational) 

                    (zero)