scirs2-linalg 0.4.2

Linear algebra module for SciRS2 (scirs2-linalg)
Documentation 
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use scirs2_core::ndarray::array;
use scirs2_linalg::compat::{self, UPLO};

#[allow(dead_code)]
fn main() {
    println!("Testing eigenvalue computation...");

    // Test 1: Diagonal matrix (should have eigenvalues [1, 3, 5])
    let diagmatrix = array![[5.0, 0.0, 0.0], [0.0, 3.0, 0.0], [0.0, 0.0, 1.0]];
    println!("Diagonal matrix: {:?}", diagmatrix);

    match compat::eigh(&diagmatrix.view(), UPLO::Lower) {
        Ok((eigenvals, eigenvecs)) => {
            println!("Eigenvalues: {:?}", eigenvals);
            println!("Eigenvectors shape: {:?}", eigenvecs.shape());
            println!("Eigenvectors: {:?}", eigenvecs);

            // Test A*V = V*Λ
            let av = diagmatrix.dot(&eigenvecs);
            let vl = eigenvecs.dot(&scirs2_core::ndarray::Array2::from_diag(&eigenvals));
            println!("A*V: {:?}", av);
            println!("V*Λ: {:?}", vl);
            println!("Difference: {:?}", &av - &vl);
        }
        Err(e) => println!("Error: {:?}", e),
    }

    // Test 2: Simple 2x2 symmetric matrix
    let simplematrix = array![[2.0, 1.0], [1.0, 3.0]];
    println!("\nSimple 2x2 matrix: {:?}", simplematrix);

    match compat::eigh(&simplematrix.view(), UPLO::Lower) {
        Ok((eigenvals, eigenvecs)) => {
            println!("Eigenvalues: {:?}", eigenvals);
            println!("Eigenvectors: {:?}", eigenvecs);

            // Test A*V = V*Λ
            let av = simplematrix.dot(&eigenvecs);
            let vl = eigenvecs.dot(&scirs2_core::ndarray::Array2::from_diag(&eigenvals));
            println!("A*V: {:?}", av);
            println!("V*Λ: {:?}", vl);
            println!("Difference: {:?}", &av - &vl);
        }
        Err(e) => println!("Error: {:?}", e),
    }
}