Struct CsrMatrix 

pub struct CsrMatrix<T: Scalar> { /* private fields */ }

Sparse matrix in CSR (Compressed Sparse Row) format.

Examples

let csr = CsrMatrix::from_triplets(
    2, 2,
    vec![0, 1], vec![0, 1], vec![1.0, 2.0],
).unwrap();
assert_eq!(csr.nnz(), 2);
assert_eq!(*csr.get(0, 0).unwrap(), 1.0);

Implementations

impl<T: Scalar> CsrMatrix<T>

pub fn new(nrows: usize, ncols: usize) -> Self

Create an empty CSR matrix.

Examples

let csr = CsrMatrix::<f64>::new(3, 3);
assert_eq!(csr.nnz(), 0);

pub fn from_triplets( nrows: usize, ncols: usize, rows: Vec<usize>, cols: Vec<usize>, values: Vec<T>, ) -> Result<Self>

Build CSR from triplet data.

Examples

let csr = CsrMatrix::from_triplets(
    2, 2,
    vec![0, 1], vec![1, 0], vec![3.0, 4.0],
).unwrap();
assert_eq!(csr.nnz(), 2);

pub fn from_dense(tensor: &Tensor<T>) -> Result<Self>

Build CSR from a dense 2-D tensor, dropping zero entries.

Examples

let dense = Tensor::from_vec(vec![1.0, 0.0, 0.0, 2.0], vec![2, 2]).unwrap();
let csr = CsrMatrix::from_dense(&dense).unwrap();
assert_eq!(csr.nnz(), 2);

pub fn nrows(&self) -> usize

Number of rows.

pub fn ncols(&self) -> usize

Number of columns.

pub fn nnz(&self) -> usize

Number of stored non-zero entries.

pub fn shape(&self) -> (usize, usize)

Shape as (nrows, ncols).

pub fn get(&self, row: usize, col: usize) -> Option<&T>

Get the value at (row, col), or None if not stored.

Examples

let csr = CsrMatrix::from_triplets(
    2, 2, vec![0], vec![1], vec![5.0],
).unwrap();
assert_eq!(*csr.get(0, 1).unwrap(), 5.0);
assert!(csr.get(0, 0).is_none());

pub fn to_dense(&self) -> Tensor<T>

Convert to a dense 2-D tensor.

Examples

let csr = CsrMatrix::from_triplets(
    2, 2, vec![0, 1], vec![0, 1], vec![1.0, 2.0],
).unwrap();
let dense = csr.to_dense();
assert_eq!(dense.as_slice(), &[1.0, 0.0, 0.0, 2.0]);

pub fn matvec(&self, x: &Tensor<T>) -> Result<Tensor<T>>

Sparse matrix x dense vector multiplication.

x must be a 1-D tensor of length ncols.

Examples

let csr = CsrMatrix::from_triplets(
    2, 2, vec![0, 1], vec![0, 1], vec![3.0, 4.0],
).unwrap();
let x = Tensor::from_vec(vec![1.0, 2.0], vec![2]).unwrap();
let y = csr.matvec(&x).unwrap();
assert_eq!(y.as_slice(), &[3.0, 8.0]);

pub fn transpose(&self) -> CscMatrix<T>

Transpose, returning a CSC matrix.

Examples

let csr = CsrMatrix::from_triplets(
    2, 3, vec![0, 1], vec![1, 2], vec![1.0, 2.0],
).unwrap();
let csc = csr.transpose();
assert_eq!(csc.nrows(), 3);
assert_eq!(csc.ncols(), 2);

pub fn to_coo(&self) -> CooMatrix<T>

Convert to COO format.

Examples

let csr = CsrMatrix::from_triplets(
    2, 2, vec![0, 1], vec![0, 1], vec![1.0, 2.0],
).unwrap();
let coo = csr.to_coo();
assert_eq!(coo.nnz(), 2);

pub fn to_csc(&self) -> CscMatrix<T>

Convert to CSC format.

Examples

let csr = CsrMatrix::from_triplets(
    2, 2, vec![0, 1], vec![0, 1], vec![1.0, 2.0],
).unwrap();
let csc = csr.to_csc();
assert_eq!(csc.nnz(), 2);

Trait Implementations

impl<T: Clone + Scalar> Clone for CsrMatrix<T>

fn clone(&self) -> CsrMatrix<T>

Returns a duplicate of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl<T: Debug + Scalar> Debug for CsrMatrix<T>

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.