Crate xsum

This crate implments xsum algorithm by Radford M. Neal (https://arxiv.org/abs/1505.05571).

xsum is able to calculate fast exact summation

⚠️ Currently, xsum supports f64 calculation only.

Usage

add_list() to take vector or array

Calculates the sum of a small-sized vector or array.

use xsum::{Xsum, XsumSmall};

let mut xsmall = XsumSmall::new();
xsmall.add_list(&vec![1.0, 2.0, 3.0]);
assert_eq!(xsmall.sum(), 6.0);

Calculates the sum of a large-sized vector or array (more than 1,000 elements).

use xsum::{Xsum, XsumLarge};

let mut xlarge = XsumLarge::new();
xlarge.add_list(&vec![1.0; 1_000]);
assert_eq!(xlarge.sum(), 1000.0);

Calculates the sum of a unknown-sized vector or array.

use xsum::{Xsum, XsumAuto};

let mut xauto = XsumAuto::new();
xauto.add_list(&vec![1.0; 1_000]);
assert_eq!(xauto.sum(), 1000.0);

add() to take a floating point number

use xsum::{Xsum, XsumSmall};

let mut xsmall = XsumSmall::new();
let vec = vec![1.0, 2.0, 3.0];
for v in vec {
    xsmall.add(v);
}
assert_eq!(xsmall.sum(), 6.0);

Chaining Method

use xsum::{Xsum, XsumExt};

let vec = vec![1.0, 2.0, 3.0];
assert_eq!(vec.xsum(), 6.0);

Structs

XsumAuto

XsumAuto is efficient if vector or array size is unknown

XsumLarge

XsumLarge is efficient if vector or array size is more 1,000

XsumSmall

XsumSmall is efficient if vector or array size is less than or equal to 1,000

Traits

Xsum

Example

XsumExt

XsumExt selects either XsumSmall or XsumLarge based on the number of elements of vector or array