Peroxide

Rust numeric library with R Syntax.

Latest README version

Corresponds with 0.4.1.

Usage

Initial Import

rust extern crate peroxide; use peroxide::*;

Vec\

```R

R

a = c(1,2,3,4) b = seq(1,5,2) # (=c(1,3,5)) ```

rust // Peroxide let a = c!(1,2,3,4); let b = seq!(1,5,2) // (=c!(1,3,5))

Matrix Declaration

```R

R

a = matrix(1:4, 2, 2, True) ```

```rust // Peroxide (All belows are same) // matrix function let a = matrix(vec![1,2,3,4], 2, 2, Row); let b = matrix(c!(1,2,3,4), 2, 2, Row); let c = matrix(seq!(1,4,1), 2, 2, Row);

// matrix macro (More convenient) let c = matrix!(1;4;1, 2, 2, Row); ```

Print

```R

R

a = matrix(1:4, 2, 2, True) print(a)

[,1] [,2]

[1,] 1 2

[2,] 3 4

```

rust // Peroxide let a = matrix!(1;4;1, 2, 2, Row); println!("{}", a); // c[0] c[1] // r[0] 1 2 // r[1] 3 4

Matrix operation

• If you want to do multiple operations on same matrix, then you should use clone because Rust std::ops consume value.

```R

R

a = matrix(1:4, 2, 2, T) b = matrix(1:4, 2, 2, F) print(a + b) print(a - b) print(a * b) print(a %*% b) ```

rust // Peroxide let a = matrix!(1;4;1, 2, 2, Row); let b = matrix!(1;4;1, 2, 2, Col); println!("{}", a.clone() + b.clone()); println!("{}", a.clone() - b.clone()); println!("{}", a.clone() * b.clone()); // Element-wise multiplication println!("{}", a % b); // Matrix multiplication // Consume -> You can't use a,b anymore.

LU Decomposition

• Peroxide uses complete pivoting LU decomposition. - Very stable.
• Also there are lots of error handling for LU, so, you should use Option

rust let a = matrix(c!(1,2,3,4), 2, 2, Row); let pqlu = a.lu().unwrap(); // for singular matrix, returns None let (p,q,l,u) = (pqlu.p, pqlu.q, pqlu.l, pqlu.u); assert_eq!(p, vec![(0,1)]); // swap 0 & 1 (Row) assert_eq!(q, vec![(0,1)]); // swap 0 & 1 (Col) assert_eq!(l, matrix(c!(1,0,0.5,1),2,2,Row)); assert_eq!(u, matrix(c!(4,3,0,-0.5),2,2,Row));

Determinant

• Determinant is implemented using by LU decomposition (O(n^3))

rust let a = matrix(c!(1,2,3,4), 2, 2, Row); assert_eq!(a.det(), -2f64);

Inverse

• Inverse is also implemented using by LU decomposition

• To handle singularity, output type is Option<Matrix>

  • To obtain inverse, you should use unwrap or pattern matching

  ```rust // Non-singular let a = matrix!(1;4;1, 2, 2, Row); assert_eq!(a.inv().unwrap(), matrix(c!(-2,1,1.5,-0.5),2,2,Row));

// Singular let b = matrix!(1;9;1, 3, 3, Row); assert_eq!(b.inv(), None); ```

Extract Column or Row

R a = matrix(1:4, 2, 2, T) print(a[,1]) print(a[,2]) print(a[1,]) print(a[2,])

rust //Peroxide let a = matrix!(1;4;1, 2, 2, Row); println!("{}", a.col(0)); println!("{}", a.col(1)); println!("{}", a.row(0)); println!("{}", a.row(1));

Functional Programming

```rust // Peroxide let a = matrix!(1;4;1, 2, 2, Row); println!("{}", a.fmap(|x| x + 1.0)); println!("{}", a.fmap(|x| x - 1.0)); println!("{}", a.fmap(|x| x * 2.0));

// Results // // c[0] c[1] // r[0] 2 3 // r[1] 4 5 // // c[0] c[1] // r[0] 0 1 // r[1] 2 3 // // c[0] c[1] // r[0] 2 4 // r[1] 6 8 ```

Version Info

To see Release.md