Function grid_search_laplace_fft 

pub(crate) fn grid_search_laplace_fft<T>(
    filename: String,
    n_points: usize,
    expansion_order_vec: &[usize],
    depth_vec: &[u64],
    block_size_vec: &[usize],
)
where
    T: RlstScalar<Real = T> + AsComplex + Default + Dft<InputType = T, OutputType = <T as AsComplex>::ComplexType> + SampleUniform + Float + Epsilon + AlignedAllocable + MatrixSvd + MatrixQr + Upcast + ArgmaxValue<T> + Cast<<T as Upcast>::Higher> + Cast<<<T as Upcast>::Higher as RlstScalar>::Real>,
    <T as AsComplex>::ComplexType: Hadamard8x8<Scalar = <T as AsComplex>::ComplexType> + AlignedAllocable,
    <T as Dft>::Plan: Sync,
    <T as Upcast>::Higher: RlstScalar + MatrixSvd + Epsilon + Cast<T>,
    <<T as Upcast>::Higher as RlstScalar>::Real: Epsilon + MatrixSvd + Cast<T::Real>,