def velpt_up_vel(w):
    """
    Description:

        Computes the VELPTMN-VLU_L1 data product from all series (ABDJ) of the instrument
        class VELPT. The units of the raw upwards velocity measurements are converted from
        mm/s to m/s. This DPA does not apply to VEL3D-K.

    Usage:

        w_mps = velpt_up_vel(w_mmps)

            where

        w_mps = Output vertical velocity VELPTMN-VLU_L1 [m/s]
        w_mmps = Input vertical velocity [mm/s]

    References:

        OOI (2012). Data Product Specification for Mean Point Water
            Velocity. Document Control Number 1341-00790.
            https://alfresco.oceanobservatories.org/ (See: Company Home
            >> OOI >> Controlled >> 1000 System Level >>
            1341-00790_Data_Product_SPEC_VELPTMN_OOI.pdf)
    """
    return w / 1000.