Function dsyevdx_buffer_size 

pub fn dsyevdx_buffer_size(
    ctx: &Context,
    mode: EigenMode,
    range: EigenRange,
    fill_mode: FillMode,
    n: usize,
    a: &DeviceMemory<f64>,
    lda: usize,
    value_range: (f64, f64),
    index_range: (usize, usize),
    w: &DeviceMemory<f64>,
) -> Result<(usize, usize)>