fdec

A collection of macros for generating fixed-size fixed-point numeric types that exactly fit your domain. The types are fully equipped for performing mathematical computations and are easy to use.

With a simple macro call you get a type that:

• has no representation errors in the range, defined by the type parameters,
• supports arithmetic operations: +, -, *, /, %, <<, >>,
• comes with mathematical functions: abs(), powi(), sqrt(),
• has special values NaN and ±Infinity, and uses them instead of panicing,
• provides basic mathematical constants,
• seamlessly interacts with Rust's primitive types,
• creates values and performs math operations on stack, avoiding heap allocations.

Usage

First, add the dependency on fdec to your Cargo.toml:

toml [dependencies] fdec = "0.2"

Second, import it at your crate's root with the macro_use attribute:

```rust

[macro_use]

extern crate fdec; ```

Now, everything is ready for adding custom numeric types to your project.

Example

Here, we define the Decimal structure that represents 160-bit numbers with 30 decimal places.

```rust

[macro_use]

extern crate fdec;

fdec32! { // Use 32-bit units module dec, // Put all the generated code into the dec module name Decimal, // Name the main struct Decimal length 5, // 5 * 32-bit units = 160 bits to store numbers scale 30 // Use 30 decimal places }

use dec::*; // Bring the generated stuff to the scope

fn main() { // Use it let a = Decimal::one(); let b = Decimal::from(14); let c = dec!(9); let result = a + 30 * (b / c).powi(3); println!("{} + 30 * ({} / {})^3 = {}", a, b, c, result); // 1 + 30 * (14 / 9)^3 = 113.92181069958847736625514403278 } ```

More examples come with the crate's source code: - Many ways to create values: creation.rs - Compute Fibonacci numbers: fibonacci.rs - Calculate square root with high precision: sqrt.rs