#decimal #financial #fixed #precision

rust_decimal_macros

Shorthand macros to assist creating Decimal types

15 releases (9 stable)

✓ Uses Rust 2018 edition

1.4.0 Mar 23, 2020
1.2.0 Jan 24, 2020
1.1.0 Dec 27, 2019
1.0.3 Aug 23, 2019
0.6.1 Nov 11, 2017

#26 in Data structures

Download history 257/week @ 2019-12-10 93/week @ 2019-12-17 342/week @ 2019-12-24 243/week @ 2019-12-31 246/week @ 2020-01-07 280/week @ 2020-01-14 340/week @ 2020-01-21 314/week @ 2020-01-28 360/week @ 2020-02-04 339/week @ 2020-02-11 281/week @ 2020-02-18 1234/week @ 2020-02-25 777/week @ 2020-03-03 843/week @ 2020-03-10 791/week @ 2020-03-17 857/week @ 2020-03-24

2,114 downloads per month
Used in 6 crates (5 directly)

MIT license

140KB
3K SLoC

Decimal   Build Status Latest Version

A Decimal implementation written in pure Rust suitable for financial calculations that require significant integral and fractional digits with no round-off errors.

The binary representation consists of a 96 bit integer number, a scaling factor used to specify the decimal fraction and a 1 bit sign. Because of this representation, trailing zeros are preserved and may be exposed when in string form. These can be truncated using the normalize or round_dp functions.

Documentation

Usage

Decimal numbers can be created in a few distinct ways. The easiest and most optimal method of creating a Decimal is to use the procedural macro within the rust_decimal_macros crate:

// Procedural macros need importing directly
use rust_decimal_macros::*;

let number = dec!(-1.23);

Alternatively you can also use one of the Decimal number convenience functions:

use rust_decimal::Decimal;

// Using an integer followed by the decimal points
let scaled = Decimal::new(202, 2); // 2.02

// From a string representation
let from_string = Decimal::from_str("2.02").unwrap(); // 2.02

// Using the `Into` trait
let my_int : Decimal = 3i32.into();

// Using the raw decimal representation
// 3.1415926535897932384626433832
let pi = Decimal::from_parts(1102470952, 185874565, 1703060790, false, 28);

Features

postgres

This feature enables a PostgreSQL communication module. It allows for reading and writing the Decimal type by transparently serializing/deserializing into the NUMERIC data type within PostgreSQL.

tokio-pg

Enables the tokio postgres module allowing for async communication with PostgreSQL.

serde-float

Enable this so that JSON serialization of Decimal types are sent as a float instead of a string (default).

e.g. with this turned on, JSON serialization would output:

{
  "value": 1.234
}

Dependencies

~0.6–0.8MB
~15K SLoC