Astro-float (astronomically large floating point numbers) is a library that implements arbitrary precision floating point numbers purely in Rust.
The library implements the basic operations and functions. It uses classical algorithms such as Karatsuba, Toom-3, Schönhage-Strassen algorithm, and others.
The library can work without the standard library provided there is a memory allocator.
## Usage
Below is an example of using the library.
For more information please refer to the library documentation: https://docs.rs/astro-float/latest/astro_float/
Calculate Pi with 1024 bit precision:
``` rust
use astro_float::BigFloatNumber;
use astro_float::Consts;
use astro_float::RoundingMode;
use astro_float::Radix;
use astro_float::Error;
// Rounding of all operations
let rm = RoundingMode::ToEven;
// Initialize mathematical constants cache
let mut cc = Consts::new().unwrap();
// Compute pi: pi = 6*arctan(1/sqrt(3))
let six = BigFloatNumber::from_word(6, 1).unwrap();
let three = BigFloatNumber::parse("3.0", Radix::Dec, 1024+8, rm).unwrap(); // +8 bits of precision to cover error
let n = three.sqrt(rm).unwrap();
let n = n.reciprocal(rm).unwrap();
let n = n.atan(rm, &mut cc).unwrap();
let mut pi = six.mul(&n, rm).unwrap();
// Reduce precision to desired
pi.set_precision(1024, rm).unwrap();
// Use library's constant for verifying the result
let pi_lib = cc.pi(1024, rm).unwrap();
// Compare computed constant with library's constant
assert!(pi.cmp(&pi_lib) == 0);
// Print computed result as decimal number
let s = pi.format(Radix::Dec, rm).unwrap();
println!("{}", s);
```
## Performance
Benchmark can be found here: https://github.com/stencillogic/bigfloat-bench.
## Roadmap
Future improvements include the implementation of faster mathematical function algorithms for arguments with large precision, such as AGM implementation for calculating the logarithm, and faster trigonometric functions.
## Contributing
The library is still young and may lack some features or contain bugs. Issues for these or other cases can be opened here: https://github.com/stencillogic/astro-float/issues