{{alias}}()
    Returns a list of matrix triangles.

    The output array contains the following matrix triangles:

    - upper: upper triangular part of a matrix.
    - lower: lower triangular part of a matrix.

    Returns
    -------
    out: Array<string>
        List of matrix triangles.

    Examples
    --------
    > var out = {{alias}}()
    [ 'upper', 'lower' ]

    See Also
    --------