kitejs/io.github.yuroyami.kitejs.dtoa/DoubleFormatter

DoubleFormatter

object DoubleFormatter

Turns a double into a set of digits and an exponent, the same code Jackson and OpenJDK use.

References:

Giulietti, "The Schubfach way to render doubles"
IEEE Computer Society, "IEEE Standard for Floating-Point Arithmetic"
Bouvier and Zimmermann, "Division-Free Binary-to-Decimal Conversion"

Divisions are avoided throughout, which helps architectures where they are slow. Section 10 of reference 1 covers that.

Functions

toDecimal

fun toDecimal(v: Double): Decimal

Converts a double to a Decimal that can then be rendered in several ways. Unlike toString this always returns a Decimal, so it is only defined for finite numbers.

toString

fun toString(v: Double): String

Converts a double to a String the way ECMAScript's Number::toString defines it. Handles every double, including the non-finite ones.