Function dsytrd 

pub fn dsytrd(
    ctx: &Context,
    fill_mode: FillMode,
    n: usize,
    a: &mut DeviceMemory<f64>,
    lda: usize,
    d: &mut DeviceMemory<f64>,
    e: &mut DeviceMemory<f64>,
    tau: &mut DeviceMemory<f64>,
    workspace: &mut DeviceMemory<f64>,
    dev_info: &mut DeviceMemory<i32>,
) -> Result<()>

Use the matching buffer-size helper to calculate the required workspace size.

The S and D data types are real valued single and double precision, respectively.

The C and Z data types are complex valued single and double precision, respectively.

Reduces a general symmetric (Hermitian) $n \times n$ matrix A to the real symmetric tridiagonal form T by an orthogonal transformation: $Q^{H}\cdot A\cdot Q = T$.

On output, A contains T and Householder reflection vectors. If fill_mode is FillMode::Upper, the diagonal and first superdiagonal of A are overwritten by T; elements above the first superdiagonal, together with tau, represent Q. If fill_mode is FillMode::Lower, the diagonal and first subdiagonal of A are overwritten by T; elements below the first subdiagonal, together with tau, represent Q.

Provide workspace through workspace. Use the corresponding *_buffer_size helper to query the required workspace length. The workspace size in bytes is size_of::<T>() * lwork.

If the reported dev_info value is -i, the ith parameter is invalid. The problem size n is limited by n * lda <= INT32_MAX primarily due to the current implementation constraints.

Errors

Returns an error if cuSOLVER has not been initialized, if the matrix dimensions, leading dimension, or fill mode are invalid, if the current GPU architecture is unsupported, or if cuSOLVER reports an internal failure.