rssn 0.2.9

A comprehensive scientific computing library for Rust, aiming for feature parity with NumPy and SymPy.
Documentation 
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82

//! Handle-based FFI API for physics sim Schrodinger quantum functions.

use num_complex::Complex;

use crate::numerical::matrix::Matrix;
use crate::physics::physics_sim::schrodinger_quantum::SchrodingerParameters;
use crate::physics::physics_sim::schrodinger_quantum::{
    self,
};

/// Runs a Schrodinger simulation and returns the final probability density as a Matrix handle (`NxxNy`).
///
/// # Safety
///
/// This function is unsafe because it dereferences raw pointers as part of the FFI boundary.
/// The caller must ensure:
/// 1. All pointer arguments are valid and point to initialized memory.
/// 2. The memory layout of passed structures matches the expected C-ABI layout.
/// 3. Any pointers returned by this function are managed according to the API's ownership rules.
#[unsafe(no_mangle)]
pub unsafe extern "C" fn rssn_physics_sim_schrodinger_run_2d(
    nx: usize,
    ny: usize,
    lx: f64,
    ly: f64,
    dt: f64,
    time_steps: usize,
    hbar: f64,
    mass: f64,
    potential_ptr: *const f64,
    initial_psi_re_ptr: *const f64,
    initial_psi_im_ptr: *const f64,
) -> *mut Matrix<f64> {
    unsafe {
        if potential_ptr.is_null() || initial_psi_re_ptr.is_null() || initial_psi_im_ptr.is_null() {
            return std::ptr::null_mut();
        }

        let n = nx * ny;

        let potential = std::slice::from_raw_parts(potential_ptr, n).to_vec();

        let re = std::slice::from_raw_parts(initial_psi_re_ptr, n);

        let im = std::slice::from_raw_parts(initial_psi_im_ptr, n);

        let mut initial_psi: Vec<Complex<f64>> = re
            .iter()
            .zip(im.iter())
            .map(|(&r, &i)| Complex::new(r, i))
            .collect();

        let params = SchrodingerParameters {
            nx,
            ny,
            lx,
            ly,
            dt,
            time_steps,
            hbar,
            mass,
            potential,
        };

        match schrodinger_quantum::run_schrodinger_simulation(&params, &mut initial_psi) {
            | Ok(snapshots) => {
                if let Some(final_state) = snapshots.last() {
                    let rows = final_state.nrows();

                    let cols = final_state.ncols();

                    let (data, _offset) = final_state.clone().into_raw_vec_and_offset();

                    Box::into_raw(Box::new(Matrix::new(rows, cols, data)))
                } else {
                    std::ptr::null_mut()
                }
            },
            | Err(_) => std::ptr::null_mut(),
        }
    }
}