tsratio

Ratio

Tiny ratio math implementation using Typescript. Stores numerator and denominator in separate numbers. All operations return new ratio instead of mutating existing one. Ratios is always stored in the simplest form.

new( num = 0, den = 1, noChecks = false )

Creates new Ratio instance. Without arguments creates ratio with 0 in the numerator and 1 in the denominator. With 1 argument creates ratio with the denominator equals 1. Third argument controls error throwing, by default there are a lot of checks during construction.

Errors

Error	Description
Ratio.ERROR_ARGUMENTS_NAN	Passed arguments are NaN
Ratio.ERROR_NUMERATOR_NAN	First arguement is NaN
Ratuo.ERROR_DENOMINATOR_NAN	Second argument is NaN
Ratio.ERROR_ARGUMENTS_NOT_INTEGER	Passed arguments are not integer
Ratio.ERROR_NUMERATOR_NOT_INTEGER	First argument is not integer
Ratio.ERROR_DENOMINATOR_NOT_INTEGER	Second argument is not integer
Ratio.ERROR_DENOMINATOR_ZERO	Second argument is zero

Getters

num => number

Returns numerator

den => number

Returns denominator

int => Ratio

Returns integer part of the ratio

frac => Ratio

Returns fractional part of the ratio

Arithmetic operations

add( r: Ratio ) => Ratio

Adds ratios.

sub( r: Ratio ) => Ratio

Subracts ratios.

mul( r: Ratio ) => Ratio

Multiplies ratios.

div( r: Ratio ) => Ratio

Divides ratios. If numerator or r is zero Ratio.ERROR_DIVISION_BY_ZERO error is thrown.

neg() => Ratio

Negation or ratio.

Logical opertions

eq( r: Ratio ) => boolean

Checks if ratios are equal.

lt( r: Ratio ) => boolean

Checks if this ratio is less than r.

le( r: Ratio ) => boolean

Checks if this ratio is less or equal to r.

ne( r: Ratio ) => boolean

Checks if ratios are not equal.

gt( r: Ratio ) => boolean

Checks if this ratio is greater than r.

ge( r: Ratio ) => boolean

Checks if this ratio is greater or equal to r.

Utility

toString() => string

Returns string representation of the Ratio. If ratio is zero returns "Ratio (0)". If ratio has denominator == 1, then returns "Ratio (n)" where n is the numerator. Otherwise returns "Ratio (n/d)", where d is the denominator.

valueOf() => number

Converts ratio to primitive number. Note that you can actually compare ratios with primitive numbers without implicit conversion, i.e.

new Ratio( 5, 2 ) == 2.5 // yields true
new Ratio( 0 ) == 0      // yields true
new Ratio( 0 ) === 0     // yields false, it's different objects

But because in many cases == is avoided, it's more like funny trick actually.

parse( s: number|string, overflowLimit = 2^53 ) => Ratio

Parses number or string and returns new Ratio. If bad arguments are passed or overflow accured during process the errors are thrown.

Errors

Error	Description
Ratio.ERROR_BAD_PARSE_ARGUMENTS	Converting input to number returned NaN
Ratio.ERROR_PARSE_OVERFLOW	During parsing we hit overflow limit, so numbers cannot be accurately represented