pyPDAF.PDAFomi.set_disttype

pyPDAF.PDAFomi.set_disttype()

Setting the observation localisation distance calculation method for i-th observation type. This is a mandatory property for OMI functionality.

Properties of obs_f are typically set in user-supplied function py__init_dim_obs_pdaf.

disttype determines the way the distance between observation and model grid is calculated in OMI. To perform distance computation, the observation coordinatesshould be given by ocoord_p argument when pyPDAF.PDAF.omi_gather_obs() is called.

See also PDAF distance computation.

Parameters:

  • i_obs (int) – index of observations

  • disttype (int) –

    Type of distance used for localisation

      1. Cartesian (any units)

      1. Cartesian periodic (any units)

    • 2) Approximation to geographic distance in metres using latitude and longitude expressed in radians

    • 3) Using Haversine formula to compute distance in metres between two points on the surface of a sphere

    • 10) 3D Cartesian distance where horizontal and vertical distances are treated separately

    • 11) 3D Cartesian periodic distance where horizontal and vertical distances are treated separately

    • 12) Same as 2) for horizontal distance but vertical distance is in units chosen by users where the horizontal and vertical distances are treated separately

    • 13) Same as 3) for horizontal distance but vertical distance is in units chosen by users where the horizontal and vertical distances are treated separately