Function mppca_denoise 

pub fn mppca_denoise(
    data: &[f64],
    dims: (usize, usize, usize),
    n_vols: usize,
    patch_radius: usize,
    mask: Option<&[u8]>,
) -> Vec<f64>

Denoise multi-volume data with MP-PCA.

Arguments

• data - Interleaved [voxel0_vol0, voxel0_vol1, ..., voxel1_vol0, ...] (row-major (n_voxels, n_vols)), the same layout as [r2star_arlo].
• dims - Volume dimensions (nx, ny, nz).
• n_vols - Number of volumes (e.g. echoes).
• patch_radius - Half-width of the cubic patch (radius 2 → 5×5×5).
• mask - Optional binary mask; masked-out voxels are copied unchanged.

Returns

Denoised data in the same layout. Voxels within patch_radius of the volume border, or outside the mask, are returned unchanged.