--- a/src/dolfinx_access.rs Thu Feb 26 09:32:12 2026 -0500
+++ b/src/dolfinx_access.rs Wed Apr 22 22:32:00 2026 -0500
@@ -1,3 +1,6 @@
+/*!
+ Utility functions accessing C++ side Dolfinx.
+*/
use alg_tools::error::DynResult;
use alg_tools::fe_model::{
base::RealLocalModel,
@@ -9,7 +12,7 @@
use std::ffi::CString;
use std::mem::MaybeUninit;
-// These are required for the linking to the sys crates to actually happen.
+/// Import helper required for the linking to the sys crates to actually happen.
#[allow(unused_imports)]
mod dummy_import {
use dolfinx_sys;
@@ -19,20 +22,29 @@
mod function;
pub use function::DolfinxPyFunction_f64;
+/// C++ side routines
#[allow(dead_code)]
#[cxx::bridge(namespace = "dolfinx_access")]
pub mod ffi {
+ /// Structure for coordinte-value pairs
#[derive(Copy, Clone, Debug)]
struct CoordValuePair {
+ /// 2D coordinate
x: [f64; 2],
+ /// Value
v: f64,
}
+ /// Structure for information about a dolfinx `Function`
#[derive(Copy, Clone, Debug)]
struct FunctionInfo {
+ /// Domain dimension
domain_dim: u32,
+ /// Codomain dimension
codomain_dim: u32,
+ /// Element order
order: u32,
+ /// Whether the mesh is triangular
triangular_mesh: bool,
}
@@ -41,7 +53,9 @@
include!("pointsource_pde/include/dolfinx_access/function.h");
include!("pointsource_pde/include/dolfinx_access/minmax_p2.h");
+ /// C++ side Dolfinx `Function<double>`
type Function_f64;
+ /// C-side python object.
type PyObject;
/// Find the cell containing `x` (in 1D, 2D, or 3D, following Fenics weirdness
@@ -66,18 +80,34 @@
cell: i32,
) -> [f64; 6];
+ /// Get information about a dolfinx `Function_f64`.
pub unsafe fn info_Function_f64(f: *const Function_f64) -> FunctionInfo;
+ /// Returns the minimum value of the Dolfinx `Function`,
+ /// if supported (P2 elements on triangular mesh)
pub unsafe fn min_Function_f64_p2(f: *const Function_f64) -> Result<CoordValuePair>;
+
+ /// Returns the maximum value of the Dolfinx `Function`,
+ /// if supported (P2 elements on triangular mesh)
pub unsafe fn max_Function_f64_p2(f: *const Function_f64) -> Result<CoordValuePair>;
+
+ /// Returns the minimum or maximum value of the Dolfinx `Function`,
+ /// if supported (P2 elements on triangular mesh)
pub unsafe fn minmax_Function_f64_p2(
f: *const Function_f64,
max: bool,
) -> Result<CoordValuePair>;
+ /// Checks if a Dolfinx `Function` is supported (P2 elements on triangular mesh)
pub unsafe fn check_Function_f64(o: *const PyObject) -> bool;
+
+ /// Casts a Python object into a Dolfinx `Function` wrapper.
pub unsafe fn cast_Function_f64(o: *const PyObject) -> Result<*const Function_f64>;
+
+ /// Casts a Python object into a mutable Dolfinx `Function` wrapper.
pub unsafe fn cast_mut_Function_f64(o: *mut PyObject) -> Result<*mut Function_f64>;
+
+ /// Gets the 3D coordinates of the nodes of a triangular cell
pub unsafe fn cell_coords_Function_f64_triangle(
f: *const Function_f64,
cell: i32,
@@ -95,18 +125,28 @@
g: *const Function_f64,
) -> Result<()>;
- /// Create a new similar function
+ /// Create a new similar Dolfinx `Function`
pub unsafe fn similar_Function_f64(f: *const Function_f64) -> *mut Function_f64;
- /// Clone the function
+ /// Clone the Dolfinx `Function`
pub unsafe fn clone_Function_f64(f: *const Function_f64) -> *mut Function_f64;
+ /// Wraps a Dolfinx `Function` into a Python object
pub unsafe fn wrap_Function_f64(f: *mut Function_f64) -> *mut PyObject;
+ /// Drop helper
pub unsafe fn drop_Function_f64(f: *mut Function_f64);
+
+ /// Scatter helper. Not truly supported.
+ pub unsafe fn scatter_fwd_Function_f64(f: *mut Function_f64);
}
extern "Rust" {
+ /// Rust-side helper for minimising P2 elements. This bypasses poorly documented basix,
+ /// and does things at a low level directly.
+ /// `f` is the function, `simplex_coords` the coorindates of the triangle
+ /// see [`cell_coords_Function_f64_triangle`], `cell` is the cell number,
+ /// and `max` indicates whether to maximise or minimise.
unsafe fn minmax_dolfinx_p2_cell(
f: *const Function_f64,
simplex_coords: &[f64; 9],