Function fpc_permutation_importance 

pub fn fpc_permutation_importance(
    fit: &FregreLmResult,
    data: &FdMatrix,
    y: &[f64],
    n_perm: usize,
    seed: u64,
) -> Result<FpcPermutationImportance, FdarError>

Permutation importance for a linear functional regression (metric = R^2).

Errors

Returns FdarError::InvalidDimension if data has zero rows, its column count does not match fit.fpca.mean, or y.len() does not match the row count. Returns FdarError::InvalidParameter if n_perm is zero. Returns FdarError::ComputationFailed if the total sum of squares is zero.