Grid definition - Lambert conformal, secant or tangent, conic or bi-polar (normal or oblique), or Albers equal-area, secant or tangent, conic or bi-polar (normal or oblique), projection

      Octet
      No.
      Contents
      7-8Nx - number of points along X-axis
      9-10Ny - number of points along Y-axis
      11-13La1 - latitude of first grid point
      14-16Lo1 - longitude of first grid point
      17Resolution and component flags (see Code table 7)
      18-20LoV - orientation of the grid; i.e. the east longitude value of the meridian which is parallel to the Y-axis (or columns of the grid) along which latitude increases as the Y-coordinate increases (the orientation longitude may or may not appear on a particular grid)
      21-23Dx - X-direction grid length (see Note 2)
      24-26Dy - Y-direction grid length (see Note 2)
      27Projection center flag (see Note 5)
      28Scanning mode (flags - see Code table 8)
      29-31Latin 1 - first latitude from the pole at which the secant cone cuts the sphere
      32-34Latin 2 - second latitude from the pole at which the secant cone cuts the sphere
      35-37Latitude of the southern pole in millidegrees (integer)
      38-40Longitude of the southern pole in millidegrees (integer)
      41-42Set to zero (reserved)



      NOTES:

      1. Latitude and longitude are in millidegrees (thousandths of a degree).

      2. Grid lengths are in units of meters, at the secant cone intersection parallel nearest to the pole on the projection plane.

      3. Latitude values are limited to the range 0-90000; bit 1 is set to 1 to indicate south latitude.

      4. Longitude values are limited to the range 0-360000; bit 1 is set to 1 to indicate west longitude.

      5. Octet 27(projection center flag):
        bit 1 set to 0 if North Pole is on the projection plane
        bit 1 set to 1 if South Pole is on the projection plane
        bit 2 set to 0 if only one projection center is used
        bit 2 set to 1 if projection is bi-polar and symmetric.

      6. If Latin 1 = Latin 2, then the projection is on a tangent code.

      7. The resolution flag (bit 1 of Code table 7) is not applicable.



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